ECG Guru - Instructor Resources - Left anterior hemiblock https://www.ecgguru.com/ecg/left-anterior-hemiblock en Non-specific IVCD With Peaked T Waves https://www.ecgguru.com/ecg/non-specific-ivcd-peaked-t-waves <div class="field field-name-field-ecg field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/ecg/non-specific-ivcd-peaked-t-waves"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/LAH102.jpg" width="1800" height="1279" alt="" /></a></div></div></div><div class="field field-name-field-ecg-interpretation field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p class="MsoNormal"><strong><span style="color: #00b050;">The Patient:</span></strong><span style="color: #00b050;"><span style="mso-spacerun: yes;">&nbsp;&nbsp; </span></span>This ECG was obtained from an elderly man who was suffering an exacerbation of congestive heart failure.<span style="mso-spacerun: yes;">&nbsp; </span>He had a history of CHF and hypertension.<span style="mso-spacerun: yes;">&nbsp; </span>We do not have other history available to us.</p><p class="MsoNormal"><strong><span style="color: #00b050;">The ECG:</span></strong><span style="color: #00b050;"><span style="mso-spacerun: yes;">&nbsp; </span></span>The <strong>rhythm is sinus at 97 bpm</strong> (fast for this patient). It is regular with no ectopy.<span style="mso-spacerun: yes;">&nbsp; </span>The <strong>PR interval is 155 ms</strong> (.15 seconds), and the P waves are upright in the inferior leads. The frontal plane QRS <strong>axis is -56 degrees</strong> – abnormally leftward.<span style="mso-spacerun: yes;">&nbsp; </span>Notice that Leads II, III, and aVF are all negative.<span style="mso-spacerun: yes;">&nbsp; </span>AVR is equiphasic – the axis travels perpendicular to the positive electrode of aVR, toward the patient’s left shoulder.<span style="mso-spacerun: yes;">&nbsp; </span>The <strong>QRS duration is 111 ms (.11 sec.).</strong><span style="mso-spacerun: yes;">&nbsp; This is very close to being wide enough for a diagnosis of left bundle branch block, and represents poor conduction throughout the ventricles.&nbsp;</span>On the chest leads side, there is <strong>poor R wave progression. </strong>V1 through V4 look almost the same, small r and large S.</p><p class="MsoNormal">The ST segments are generally concave up, and the J points are at the baseline – <strong>no ST elevation or depression.<span style="mso-spacerun: yes;">&nbsp; </span></strong>There are <strong>no pathological Q waves</strong>, unless we count V1, which may have lost it’s Q wave as part of the general poor R wave progression.</p><p class="MsoNormal"><strong><span style="color: #00b050;">Interpretation:</span></strong><span style="color: #00b050;"><span style="mso-spacerun: yes;">&nbsp; </span></span>The fast rate is probably attributable to the patient’s difficulty breathing, as this ECG was obtained in the Emergency Department before treatment had a chance to alleviate his symptoms. The other most noticeable abnormality on this ECG is the axis shift – normally, Lead II is positive.<span style="mso-spacerun: yes;">&nbsp; </span>While there are many reasons for axis shift (myocardial infarction, chamber enlargement, body habitus, etc.), nearly all can be ruled out in this patient.<span style="mso-spacerun: yes;">&nbsp; </span>Instead, he has the ECG signs of <strong>left anterior fascicular block,</strong> also called left anterior hemiblock.<span style="mso-spacerun: yes;">&nbsp; </span>Think of it as half a left bundle branch block, because the left anterior fascicle is blocked while the posterior fascicle is still conducting.<span style="mso-spacerun: yes;">&nbsp; </span>The effects on the ECG are:</p><p class="MsoListParagraphCxSpFirst" style="text-indent: -.25in; mso-list: l0 level1 lfo1;"><!--[if !supportLists]--><span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span></span><!--[endif]-->Left axis deviation, greater than -45 degrees.</p><p class="MsoListParagraphCxSpMiddle" style="text-indent: -.25in; mso-list: l0 level1 lfo1;"><!--[if !supportLists]--><span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span></span><!--[endif]-->A slightly widened QRS.</p><p class="MsoListParagraphCxSpMiddle" style="text-indent: -.25in; mso-list: l0 level1 lfo1;"><!--[if !supportLists]--><span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span></span><!--[endif]-->qR pattern in Leads I and aVL (lateral leads).</p><p class="MsoListParagraphCxSpMiddle" style="text-indent: -.25in; mso-list: l0 level1 lfo1;"><!--[if !supportLists]--><span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span></span><!--[endif]-->rS pattern in inferior leads.</p><p class="MsoListParagraphCxSpLast" style="text-indent: -.25in; mso-list: l0 level1 lfo1;"><!--[if !supportLists]--><span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span></span><!--[endif]-->Possible interference in normal R wave progression, producing a pattern that resembles anterior M.I.</p><p class="MsoNormal">Studies have shown some association of LAFB with other cardiac conditions like CHF and atrial fib. But, as a single ECG finding, it is considered rather benign, possibly signaling fibrosis or other disease beginning to affect the interventricular conduction system.</p><p class="MsoNormal">EDIT: After writing this, Drs Grauer, Jones, and Parrinello were kind enough to weigh in on the significance of the wide QRS and the tall T waves. Please read their comments below for a fuller understanding of this ECG.&nbsp;</p><p class="MsoNormal">Had we more information about the patient, we would not have to speculate. ECGs are best evaluated with full clinical information.&nbsp;</p></div></div></div><div class="field field-name-field-rate-this-content field-type-fivestar field-label-above"><div class="field-label">Rate this content:&nbsp;</div><div class="field-items"><div class="field-item even"><form class="fivestar-widget" action="/taxonomy/term/42/feed" method="post" id="fivestar-custom-widget" accept-charset="UTF-8"><div><div class="clearfix fivestar-average-text fivestar-average-stars fivestar-form-item fivestar-hearts"><div class="form-item form-type-fivestar form-item-vote"> <div class="form-item form-type-select form-item-vote"> <select id="edit-vote--2" name="vote" class="form-select"><option value="-">Select rating</option><option value="20">Give Non-specific IVCD With Peaked T Waves 1/5</option><option value="40">Give Non-specific IVCD With Peaked T Waves 2/5</option><option value="60">Give Non-specific IVCD With Peaked T Waves 3/5</option><option value="80" selected="selected">Give Non-specific IVCD With Peaked T Waves 4/5</option><option value="100">Give Non-specific IVCD With Peaked T Waves 5/5</option></select> <div class="description"><div class="fivestar-summary fivestar-summary-average-count"><span class="average-rating">Average: <span >3.2</span></span> <span class="total-votes">(<span >94</span> votes)</span></div></div> </div> </div> </div><input class="fivestar-submit form-submit" type="submit" id="edit-fivestar-submit" name="op" value="Rate" /><input type="hidden" name="form_build_id" value="form-xKsSIRIdgQ_7arKHtnLpBEMwPqlTYuhV4ICYDoH-Qrc" /> <input type="hidden" name="form_id" value="fivestar_custom_widget" /> </div></form></div></div></div><div class="field field-name-field-taxonomy field-type-taxonomy-term-reference field-label-above"><div class="field-label">Related Terms:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="/ecg/left-anterior-fascicular-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior fascicular block</a></div><div class="field-item odd"><a href="/ecg/ivcd" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">IVCD</a></div><div class="field-item even"><a href="/ecg/hyperacute-t-waves" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Hyperacute T waves</a></div><div class="field-item odd"><a href="/ecg/left-anterior-hemiblock" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior hemiblock</a></div><div class="field-item even"><a href="/ecg/intraventricular-conduction-delay" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Intraventricular conduction delay</a></div><div class="field-item odd"><a href="/ecg/poor-r-wave-progression-0" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Poor R wave progression</a></div></div></div><ul class="links inline"><li class="addtoany first last"><span><span class="a2a_kit a2a_target addtoany_list" id="da2a_1"> <a class="a2a_dd addtoany_share_save" href="https://www.addtoany.com/share#url=https%3A%2F%2Fwww.ecgguru.com%2Fecg%2Fnon-specific-ivcd-peaked-t-waves&amp;title=%20Non-specific%20IVCD%20With%20Peaked%20T%20Waves%20"><img src="/sites/all/modules/addtoany/images/share_save_256_24.png" width="256" height="24" alt="Share"/></a> </span> <script type="text/javascript"> <!--//--><![CDATA[//><!-- if(window.da2a)da2a.script_load(); //--><!]]> </script></span></li> </ul> Mon, 31 May 2021 19:58:30 +0000 Dawn 798 at https://www.ecgguru.com https://www.ecgguru.com/ecg/non-specific-ivcd-peaked-t-waves#comments Wide Complex Tachycardia https://www.ecgguru.com/ecg/wide-complex-tachycardia-5 <div class="field field-name-field-ecg field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/ecg/wide-complex-tachycardia-5"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/18-18%20Edited.jpg" width="1800" height="646" alt="" /></a></div><div class="field-item odd"><a href="/ecg/wide-complex-tachycardia-5"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/18-31%20%20%20Edited.jpg" width="1800" height="652" alt="" /></a></div></div></div><div class="field field-name-field-ecg-interpretation field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p class="MsoNormal" style="margin-bottom: 0in; line-height: normal;"><span style="font-size: 14.0pt;">This pair of ECGs feature one of our recurring themes:<span style="mso-spacerun: yes;">&nbsp; </span>wide-complex tachycardia (WCT). It is a fascinating topic, as tachycardia has many causes and many mechanisms, and wide QRS also has many causes, with the mechanism being slow conduction through the ventricles.</span><span style="font-size: 14pt;">&nbsp;</span></p><p class="MsoNormal" style="margin-bottom: 0in; line-height: normal;"><span style="font-size: 14.0pt;">Sometimes, it is not possible to diagnose the true origin of a WCT from one ECG, or even serial ECGs.<span style="mso-spacerun: yes;">&nbsp; </span>Is the tachycardia due to increased sympathetic activity (fear, dehydration, exercise, hypoxia, hypovolemia, etc.)?<span style="mso-spacerun: yes;">&nbsp; </span>Or is the fast rate due to reentry, where one impulse gets “caught” in a loop, repeating itself rapidly, and depolarizing the myocardium with each pass?<span style="mso-spacerun: yes;">&nbsp; </span>What is the location of the pacemaker that is responsible for the rhythm?<span style="mso-spacerun: yes;">&nbsp; </span>Is it a supraventricular rhythm that has suffered an intraventricular conduction delay, widening the QRS?<span style="mso-spacerun: yes;">&nbsp; </span>Or is the rhythm originating in a ventricular pacemaker, without the ability to travel on the fast highway that is the intraventricular conduction system?</span><span style="font-size: 14pt;">&nbsp;</span></p><p class="MsoNormal" style="margin-bottom: 0in; line-height: normal;"><span style="font-size: 14.0pt;">If you or your students work in an acute care setting, such as pre-hospital or emergency department, you may not be with the patient long enough or be able to conduct enough tests to determine without a doubt the answers to the above questions.<span style="mso-spacerun: yes;">&nbsp; </span>Some WCTs cause such severe symptoms that they must be dealt with quickly, to avoid rapid deterioration to ventricular fibrillation.<span style="mso-spacerun: yes;">&nbsp; </span>For that reason, there is a widely-accepted rule for WTC treatment:</span></p><p class="MsoNormal" style="margin-bottom: 0in; line-height: normal;"><strong><span style="font-size: 14.0pt; color: #c00000;">TREAT ALL WIDE-COMPLEX TACHYCARDIA AS IF IT IS V TACH UNTIL PROVEN OTHERWISE. <span style="mso-spacerun: yes;">&nbsp;</span><span style="mso-spacerun: yes;">&nbsp;</span></span></strong><strong><span style="font-size: 14.0pt; color: #c00000;">&nbsp;</span></strong></p><p class="MsoNormal" style="margin-bottom: 0in; line-height: normal;"><strong><span style="font-size: 14.0pt; color: #00b050;">The Patient:</span></strong><span style="font-size: 14.0pt; color: #00b050;"><span style="mso-spacerun: yes;">&nbsp; </span></span><span style="font-size: 14.0pt;">These two tracings were taken from an elderly man who complained of feeling sick. He was found by paramedics to be alert, diaphoretic, tachypneic, and complaining of palpitations. His initial vital signs were:<span style="mso-spacerun: yes;">&nbsp; </span>BP 80/60, Pulse 167 and regular, respirations 30/min. Pulse oximetry 96%.</span><span style="font-size: 14pt;">&nbsp;</span></p><p class="MsoNormal" style="margin-bottom: 0in; line-height: normal;"><strong><span style="font-size: 14.0pt; color: #00b050;">ECG No. 1 at 18:18:44<span style="mso-spacerun: yes;">&nbsp; </span></span></strong><span style="font-size: 14.0pt;">The rhythm is regular at 167/min.<span style="mso-spacerun: yes;">&nbsp; </span>The QRS width is about .12 seconds (120 ms). It is difficult to measure the QRS width with precision due to artifact and slurred terminal portions of most of the QRS complexes. No clear P waves are seen, possibly due to the rate causing P-on-T.<span style="mso-spacerun: yes;">&nbsp; </span>Several features of the QRS morphology suggest VENTRICULAR TACHYCARDIA, including the extreme axis (almost vertical), and the negative deflection in Lead V6. When V tach has this pattern: <span style="mso-spacerun: yes;">&nbsp;</span>a minimally-wide QRS with a right bundle branch block pattern, it is usually “fascicular ventricular tachycardia”.</span><span style="font-size: 14pt;">&nbsp;</span></p><p class="MsoNormal" style="margin-bottom: 0in; line-height: normal;"><strong><span style="font-size: 14.0pt; color: #00b050;">Initial Treatment:<span style="mso-spacerun: yes;">&nbsp; </span></span></strong><span style="font-size: 14.0pt;">Because of the patient’s hemodynamic instability and symptoms, the EMS crew elected to follow the above rule and treat this rhythm as VENTRICULAR TACHYCARDIA.<span style="mso-spacerun: yes;">&nbsp; </span>He was administered Amiodarone 150 mg IV while the crew prepared to cardiovert him under light sedation.<span style="mso-spacerun: yes;">&nbsp; </span>As soon as they were able, he was cardioverted with 120 j.<span style="mso-spacerun: yes;">&nbsp; </span>The new rhythm is shown in ECG #2.</span><span style="font-size: 14pt;">&nbsp;</span></p><p class="MsoNormal" style="margin-bottom: 0in; line-height: normal;"><strong><span style="font-size: 14.0pt; color: #00b050;">ECG No. 2 at 18:31:55 <span style="mso-spacerun: yes;">&nbsp;</span></span></strong><span style="font-size: 14.0pt;">The patient’s rhythm remains regular at about 130 / min.&nbsp;</span><span style="font-size: 14pt;">Respiratory rate 20/min. and unlabored.</span><span style="font-size: 14pt;">&nbsp; </span><span style="font-size: 14pt;">BP 92/58.</span><span style="font-size: 14pt;">&nbsp; </span><span style="font-size: 14pt;">Pulse ox: 97% on nasal O2.</span></p><p class="MsoNormal" style="margin-bottom: 0in; line-height: normal;"><span style="font-size: 14.0pt;">The most interesting finding is the QRS morphology has not changed.<span style="mso-spacerun: yes;">&nbsp; </span>The width is still .12 sec., and the axis and other features of the QRS complexes are the same as they were in the faster rhythm.<span style="mso-spacerun: yes;">&nbsp; </span>In addition, in spite of the artifact, I feel that P waves are present.<span style="mso-spacerun: yes;">&nbsp; </span>A cleaner ECG might prove it, but I am confident of the P waves in Leads II, III and V3.<span style="mso-spacerun: yes;">&nbsp; </span>I will readily admit that a clear, artifact-free ECG might prove me wrong.<span style="mso-spacerun: yes;">&nbsp; </span>If this is SINUS TACHYCARDIA, the first ECG was most certainly not V Tach, because the QRS complexes haven’t changed.<span style="mso-spacerun: yes;">&nbsp; </span>If we accept that there are P waves, the first rhythm was paroxysmal supraventricular tachycardia.<span style="mso-spacerun: yes;">&nbsp; </span>The wide complexes would be due to right bundle branch block and anterior superior fascicular block (also called hemiblock).<span style="mso-spacerun: yes;">&nbsp; </span>The RBBB causes rSR’ pattern in V1 and wide S waves in I and V6, and explains the slightly widened QRS.</span></p><p class="MsoNormal" style="margin-bottom: 0in; line-height: normal;"><span style="font-size: 14.0pt;">The fascicular block causes the extreme left axis shift.<span style="mso-spacerun: yes;">&nbsp; </span></span></p><p class="MsoNormal" style="margin-bottom: 0in; line-height: normal;"><span style="font-size: 14.0pt;">If you don’t see P waves, then we would have to explain how the cardioversion changed the rhythm from a “fast V Tach” to a “slow V Tach.”</span><span style="font-size: 14pt;">&nbsp;</span></p><p class="MsoNormal" style="margin-bottom: 0in; line-height: normal;"><strong><span style="font-size: 14.0pt; color: #00b050;">Patient Outcome:<span style="mso-spacerun: yes;">&nbsp; </span></span></strong><span style="font-size: 14.0pt;">The crew, by treating this WCT as V tach, obtained a quick improvement in the rate, which helped with the symptoms.<span style="mso-spacerun: yes;">&nbsp; </span>Amiodarone and cardioversion are both appropriate treatments for V tach and PSVT.</span><span style="font-size: 14pt;">&nbsp;</span></p><p class="MsoNormal" style="margin-bottom: 0in; line-height: normal;"><span style="font-size: 14.0pt;">The patient was diagnosed at the hospital with “arrhythmia due to an infection, combined with effects of a weight-loss medication”.<span style="mso-spacerun: yes;">&nbsp; </span>He had a cardiac catheterization which was negative for significant coronary artery disease. We have no information on the diagnosis of the arrhythmia, or what his ECG looked like on discharge, one week later.</span><span style="font-size: 14pt;">&nbsp;</span></p><p class="MsoNormal" style="margin-bottom: 0in; line-height: normal;"><strong><span style="font-size: 14.0pt; color: #00b050;">As always, we welcome your comments and opinions on this case.</span></strong><span style="font-size: 14pt;">&nbsp;</span></p><p class="MsoNormal" style="margin-bottom: 0in; line-height: normal;"><em><span style="font-size: 9.0pt;">Many thanks to Lt. Curtis Jepsen for donating these tracings. </span></em></p></div></div></div><div class="field field-name-field-rate-this-content field-type-fivestar field-label-above"><div class="field-label">Rate this content:&nbsp;</div><div class="field-items"><div class="field-item even"><form class="fivestar-widget" action="/taxonomy/term/42/feed" method="post" id="fivestar-custom-widget--2" accept-charset="UTF-8"><div><div class="clearfix fivestar-average-text fivestar-average-stars fivestar-form-item fivestar-hearts"><div class="form-item form-type-fivestar form-item-vote"> <div class="form-item form-type-select form-item-vote"> <select id="edit-vote--4" name="vote" class="form-select"><option value="-">Select rating</option><option value="20">Give Wide Complex Tachycardia 1/5</option><option value="40">Give Wide Complex Tachycardia 2/5</option><option value="60">Give Wide Complex Tachycardia 3/5</option><option value="80" selected="selected">Give Wide Complex Tachycardia 4/5</option><option value="100">Give Wide Complex Tachycardia 5/5</option></select> <div class="description"><div class="fivestar-summary fivestar-summary-average-count"><span class="average-rating">Average: <span >3.3</span></span> <span class="total-votes">(<span >100</span> votes)</span></div></div> </div> </div> </div><input class="fivestar-submit form-submit" type="submit" id="edit-fivestar-submit--2" name="op" value="Rate" /><input type="hidden" name="form_build_id" value="form-OeHhelEe4dxq_T91RzfjZYs-qcG6sq1LP-7xwFAaFFo" /> <input type="hidden" name="form_id" value="fivestar_custom_widget" /> </div></form></div></div></div><div class="field field-name-field-taxonomy field-type-taxonomy-term-reference field-label-above"><div class="field-label">Related Terms:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="/ecg/wide-complex-tachycardia" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Wide complex tachycardia</a></div><div class="field-item odd"><a href="/ecg/wide-qrs" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Wide QRS</a></div><div class="field-item even"><a href="/ecg/ventricular-tachycardia" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Ventricular tachycardia</a></div><div class="field-item odd"><a href="/ecg/right-bundle-branch-block-1" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Right bundle branch block</a></div><div class="field-item even"><a href="/ecg/left-anterior-fascicular-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior fascicular block</a></div><div class="field-item odd"><a href="/ecg/left-anterior-hemiblock" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior hemiblock</a></div><div class="field-item even"><a href="/ecg/fascicular-tachycardia" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Fascicular tachycardia</a></div></div></div><ul class="links inline"><li class="addtoany first last"><span><span class="a2a_kit a2a_target addtoany_list" id="da2a_2"> <a class="a2a_dd addtoany_share_save" href="https://www.addtoany.com/share#url=https%3A%2F%2Fwww.ecgguru.com%2Fecg%2Fwide-complex-tachycardia-5&amp;title=%20Wide%20Complex%20Tachycardia"><img src="/sites/all/modules/addtoany/images/share_save_256_24.png" width="256" height="24" alt="Share"/></a> </span> </span></li> </ul> Sat, 06 Feb 2021 03:11:12 +0000 Dawn 797 at https://www.ecgguru.com https://www.ecgguru.com/ecg/wide-complex-tachycardia-5#comments High-grade AV Block With Profound Bradycardia https://www.ecgguru.com/ecg/high-grade-av-block-profound-bradycardia <div class="field field-name-field-ecg field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/ecg/high-grade-av-block-profound-bradycardia"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/AVB120%20High%20grade%20w%20sinus%20brady.jpg" width="1800" height="768" alt="" /></a></div></div></div><div class="field field-name-field-ecg-interpretation field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p class="MsoNormal">If you are an ECG instructor, you probably carefully choose ECGs to illustrate the topic you are teaching. One of the reasons for the existence of the ECG Guru website is our desire to provide lots of such illustrations for you to choose from.</p><p class="MsoNormal">Sometimes, though, an ECG does not clearly illustrate one specific dysrhythmia well, because the interpretation of the ECG depends on so many other factors.<span style="mso-spacerun: yes;">&nbsp; </span>In order to get it “right”, we would need to know information about the patient’s history, presentation, lab results, or previous ECGs. We might need to see the ECG done immediately before or after the one we are looking at.<span style="mso-spacerun: yes;">&nbsp; </span>Some ECG findings must ultimately be confirmed by an electrophysiology study before we can know for sure what is going on.</p><p class="MsoNormal">For those of us who are “ECG nerds”, it can be fun to debate our opinions and even more fun to hear from wiser, more advanced practitioners about their interpretations.</p><p class="MsoNormal">My belief, as a clinical instructor, is that we must teach strategies for treating the patient who has a “controversial” ECG that take into account the level of the practitioner, the care setting, and the patient’s hemodynamic status.<span style="mso-spacerun: yes;">&nbsp; </span>In some settings, it might be absolutely forbidden for a first-responder to cardiovert atrial fibrillation, for example.<span style="mso-spacerun: yes;">&nbsp; </span>But atrial fib is routinely cardioverted under controlled conditions in hospitals.<span style="mso-spacerun: yes;">&nbsp; </span>The general rule followed by emergency providers that “all wide-complex tachycardias are v tach until proven otherwise” has no doubt prevented deaths in situations where care providers did not agree on the origin of the tachycardia.</p><p class="MsoNormal"><strong><span style="color: #00b050;">The ECG: <span style="mso-spacerun: yes;">&nbsp;</span><span style="mso-spacerun: yes;">&nbsp;</span><span style="mso-spacerun: yes;">&nbsp;</span></span></strong>We do not have much patient information to go with this ECG, just that it is from a 71-year-old woman who developed severe hypotension and lost consciousness, but was revived with transcutaneous pacing.<span style="mso-spacerun: yes;">&nbsp;&nbsp; </span>Here is what we do know about this ECG:</p><p class="MsoListParagraphCxSpFirst" style="text-indent: -.25in; mso-list: l0 level1 lfo1;"><!--[if !supportLists]--><span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span></span><!--[endif]-->There are regular P waves, at a rate of about 39 bpm (sinus bradycardia).</p><p class="MsoListParagraphCxSpMiddle" style="text-indent: -.25in; mso-list: l0 level1 lfo1;"><!--[if !supportLists]--><span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span></span><!--[endif]-->There are only two QRS complexes, shown in a total of six leads, and the rate is 13 bpm.</p><p class="MsoListParagraphCxSpMiddle" style="text-indent: -.25in; mso-list: l0 level1 lfo1;"><!--[if !supportLists]--><span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span></span><!--[endif]-->The two PR intervals that are seen are the same at 368 ms, or .368 seconds (first-degree AVB).</p><p class="MsoListParagraphCxSpMiddle" style="text-indent: -.25in; mso-list: l0 level1 lfo1;"><!--[if !supportLists]--><span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span></span><!--[endif]-->There are three P waves for every QRS complex. (second-degree AVB, Type II).</p><p class="MsoListParagraphCxSpMiddle" style="text-indent: -.25in; mso-list: l0 level1 lfo1;"><!--[if !supportLists]--><span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span></span><!--[endif]-->The QRS complexes are 144 ms wide (.14 seconds).</p><p class="MsoListParagraphCxSpLast" style="text-indent: -.25in; mso-list: l0 level1 lfo1;"><!--[if !supportLists]--><span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span></span><!--[endif]-->The QRS morphology cannot be evaluated in 12 leads here, but the pattern is consistent with right bundle branch block and left anterior fascicular block (bifascicular block).<span style="mso-spacerun: yes;">&nbsp; </span>Were we at the bedside, another 10 seconds of 12-lead ECG might produce a QRS that falls into the remaining leads’ sections of the tracing.</p><p class="MsoNormal">It would be very important to determine what caused the severe slowing of conduction. The paper speed has not been altered, and that should be ruled out whenever all rates and intervals are prolonged.<span style="mso-spacerun: yes;">&nbsp; </span>The severe sinus bradycardia, second-degree AVB, first-degree AVB, and bundle branch block all point to a global cause of poor conduction.<span style="mso-spacerun: yes;">&nbsp; </span>Electrolytes, drugs, vagal stimulation, possible acute M.I. – all of these need to be assessed.<span style="mso-spacerun: yes;">&nbsp; </span>And, eventually, the best definitive treatment will need to be decided.</p><p class="MsoNormal">But what is the <strong>MOST IMPORTANT </strong>issue here?<span style="mso-spacerun: yes;">&nbsp; </span><strong><span style="color: #c00000;">The RATE!</span></strong><span style="color: #c00000;"><span style="mso-spacerun: yes;">&nbsp; </span></span>And the patient’s response to the extremely slow rate.<span style="mso-spacerun: yes;">&nbsp; </span>Before we spend any time on the cause or treatment, we must address the rate and the patient’s hemodynamic status.<span style="mso-spacerun: yes;">&nbsp; </span>A transcutaneous pacemaker, if available, is called for.<span style="mso-spacerun: yes;">&nbsp; </span>CPR may be needed until the pacemaker can provide a perfusing rate. Rate-enhancing drugs may be used, and temporary transvenous pacing.<span style="mso-spacerun: yes;">&nbsp; </span>If the patient’s perfusion status is not addressed, the rest will not matter.</p><p class="MsoNormal">When students are taking an ECG class, they most often want to know, “what is the name of this rhythm?” and “what are some shortcuts or mnemonics I can use to remember the names of the rhythms?”.<span style="mso-spacerun: yes;">&nbsp; </span>They will be distressed if the instructor says, “This could be second-degree AVB, or we could call it high-grade AVB, or a longer strip might show it to be third-degree AVB.”<span style="mso-spacerun: yes;">&nbsp; </span>The instructor may even feel distressed by not knowing “for sure.”<span style="mso-spacerun: yes;">&nbsp; </span>But (and this is admittedly an editorial on my part), I think we do our students a disservice to lead them to believe that there is a “right” answer to every ECG strip. They need to know that some ECGs cannot and should not be read in a vacuum, but rather in light of the patient’s information. They need to know that comparison with a previous ECG, or adding additional leads, or running a longer strip may illuminate the problem.<span style="mso-spacerun: yes;">&nbsp; </span>But most of all, they should understand what immediate actions can safely be taken until we do “know for sure”.</p><p class="MsoNormal">We welcome your comments on this topic, whether you are a teacher, a student, a provider, or all of these.</p></div></div></div><div class="field field-name-field-rate-this-content field-type-fivestar field-label-above"><div class="field-label">Rate this content:&nbsp;</div><div class="field-items"><div class="field-item even"><form class="fivestar-widget" action="/taxonomy/term/42/feed" method="post" id="fivestar-custom-widget--3" accept-charset="UTF-8"><div><div class="clearfix fivestar-average-text fivestar-average-stars fivestar-form-item fivestar-hearts"><div class="form-item form-type-fivestar form-item-vote"> <div class="form-item form-type-select form-item-vote"> <select id="edit-vote--6" name="vote" class="form-select"><option value="-">Select rating</option><option value="20">Give High-grade AV Block With Profound Bradycardia 1/5</option><option value="40">Give High-grade AV Block With Profound Bradycardia 2/5</option><option value="60">Give High-grade AV Block With Profound Bradycardia 3/5</option><option value="80" selected="selected">Give High-grade AV Block With Profound Bradycardia 4/5</option><option value="100">Give High-grade AV Block With Profound Bradycardia 5/5</option></select> <div class="description"><div class="fivestar-summary fivestar-summary-average-count"><span class="average-rating">Average: <span >3.5</span></span> <span class="total-votes">(<span >27</span> votes)</span></div></div> </div> </div> </div><input class="fivestar-submit form-submit" type="submit" id="edit-fivestar-submit--3" name="op" value="Rate" /><input type="hidden" name="form_build_id" value="form-75Eneglld5IeyH1b7eUcosrWyU4i9Abu7ORPfHo1CFc" /> <input type="hidden" name="form_id" value="fivestar_custom_widget" /> </div></form></div></div></div><div class="field field-name-field-taxonomy field-type-taxonomy-term-reference field-label-above"><div class="field-label">Related Terms:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="/ecg/high-grade-av-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">High-grade AV Block</a></div><div class="field-item odd"><a href="/ecg/sinus-bradycardia" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Sinus bradycardia</a></div><div class="field-item even"><a href="/ecg/second-degree-av-block-type-ii" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Second-degree AV block Type II</a></div><div class="field-item odd"><a href="/ecg/right-bundle-branch-block-1" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Right bundle branch block</a></div><div class="field-item even"><a href="/ecg/left-anterior-fascicular-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior fascicular block</a></div><div class="field-item odd"><a href="/ecg/left-anterior-hemiblock" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior hemiblock</a></div><div class="field-item even"><a href="/ecg/bifascicular-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Bifascicular block</a></div><div class="field-item odd"><a href="/ecg/first-degree-av-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">First-degree AV block</a></div></div></div><ul class="links inline"><li class="addtoany first last"><span><span class="a2a_kit a2a_target addtoany_list" id="da2a_3"> <a class="a2a_dd addtoany_share_save" href="https://www.addtoany.com/share#url=https%3A%2F%2Fwww.ecgguru.com%2Fecg%2Fhigh-grade-av-block-profound-bradycardia&amp;title=High-grade%20AV%20Block%20With%20Profound%20Bradycardia"><img src="/sites/all/modules/addtoany/images/share_save_256_24.png" width="256" height="24" alt="Share"/></a> </span> </span></li> </ul> Thu, 04 Jun 2020 20:24:18 +0000 Dawn 785 at https://www.ecgguru.com https://www.ecgguru.com/ecg/high-grade-av-block-profound-bradycardia#comments Syncope and tachycardia https://www.ecgguru.com/ecg/syncope-and-tachycardia <div class="field field-name-field-ecg field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/ecg/syncope-and-tachycardia"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/MR112%20Wide%20complex%20rhythm.jpg" width="2000" height="765" alt="" /></a></div></div></div><div class="field field-name-field-ecg-interpretation field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><strong>The patient:</strong>&nbsp; This ECG is taken from a 55-year-old man whose wife called 911 because he had a syncopal episode.&nbsp; When the paramedics arrived, he was conscious and alert, and denied any symptoms.&nbsp; He gave a history of "cardiac", diabetes, and opiate abuse.&nbsp; We do not know the nature of his cardiac history or his medications.&nbsp;&nbsp;</p><p>It is difficult to pinpoint a definite diagnosis with this lack of information and a clearly abnormal ECG.&nbsp; We will limit our discussion to listing the abnormalities seen:</p><p><strong>The ECG rhythm:</strong>&nbsp; There is a fast, regular rhythm that is supraventricular in origin (there are P waves).&nbsp; When a supraventricular rhythm has a rate of about 150 per minute, we should ALWAYS consider ATRIAL FLUTTER WITH 2:1 CONDUCTION.&nbsp; Atrial flutter produces P waves (flutter waves) at approximately 250-350 per minute.&nbsp; The normal AV node is able to conduct half of these, at a rate of about 150 per minute. Atrial flutter with 2:1 conduction is the most common presentation of new-onset atrial flutter.&nbsp; It is often missed by people who expect to see several flutter waves in a row, producing the "sawtooth pattern".&nbsp; That being said, atrial flutter is usually discernable in at least a few leads if it is present.&nbsp; We do not see any signs of flutter waves in this ECG.</p><p>That leaves us with a differential diagnosis of sinus tachycardia vs. one of the regular supraventricular tachycardias like reentrant tachycardias or atrial tachycardia.&nbsp; Sinus tachycardia can be recognized by several features. If we are fortunate enough to witness the onset or offset of the fast rhythm, will will recognize sinus tachycardia by a "warm up" or gradual speeding up of the rate, and a "cool down", or gradual slowing.&nbsp; On the other hand, SVTs often have abrupt onset and offset.&nbsp; Sinus tachycardia often has a very obvious cause, such as hypovolemia, fever, pain, anxiety, vigorous exercise, or hypoxia.&nbsp; Sinus tachycardia usually has a distinct, upright P wave in Lead II, and a clearly-seen, often negative, P wave in Lead V1.&nbsp; This ECG does not show the onset of the tachycardia, and is not long enough to evaluate for rate changes. Lead II appears to have upright P waves on the downslope of the previous T waves. V1 has deeply negative P waves, and V4 has the most clearly-seen P waves.&nbsp; Without being positive, this looks more like sinus tachycardia than a reentrant tachycardia.&nbsp; It would help to know more about the patient's condition.</p><p><strong>The QRS complexes:</strong>&nbsp; The QRS complexes are slightly wide at .106 seconds.&nbsp; This is not wide enough to consider bundle branch block.&nbsp; Other conditions can cause widening, such as left ventricular hypertrophy and hemiblock, as well as some drug and electrolyte effects.&nbsp; The frontal plane axis is abnormally leftward, which supports a left anterior hemiblock (left anterior fascicular block) diagnosis. There is not a distinct qR pattern in Lead I or rS in Lead III, however.&nbsp; Lead aVF appears to have a pathological Q wave - could this be why Lead III does not have a distinct r wave?&nbsp; &nbsp;</p><p>While the chest leads do not show increased voltage that would indicate left ventricular hypertrophy, the left axis and the tall QRS in aVL do meet the criteria for LVH.&nbsp; LVH is not diagnosed by ECG, but it does cause changes on the ECG, such as increased voltage in left-sided leads and a "strain" pattern.&nbsp; Leads I and aVL demonstrate the strain pattern of downsloping ST segments and T wave inversion, but the chest leads do not.&nbsp; &nbsp;</p><p>The QRS complexes in V2, V3, and V4 are fragmented, which is an equivalent to pathological Q wave.&nbsp; This may indicate a prior anterior wall M.I.&nbsp; There is very slight J-point elevation in the right-sided chest leads, but may be due to LVH.</p><p>Without knowing more about this patient's past medical history, or the results of his physical exam, it is difficult to assign meaning to all these abnormal findings.&nbsp; It is unfortunate that he refused transport to a hospital, and we can only hope that he later found his way there for treatment.</p><p>Many thanks to Jon Hamilton for donating this ECG to the ECG Guru</p></div></div></div><div class="field field-name-field-rate-this-content field-type-fivestar field-label-above"><div class="field-label">Rate this content:&nbsp;</div><div class="field-items"><div class="field-item even"><form class="fivestar-widget" action="/taxonomy/term/42/feed" method="post" id="fivestar-custom-widget--4" accept-charset="UTF-8"><div><div class="clearfix fivestar-average-text fivestar-average-stars fivestar-form-item fivestar-hearts"><div class="form-item form-type-fivestar form-item-vote"> <div class="form-item form-type-select form-item-vote"> <select id="edit-vote--8" name="vote" class="form-select"><option value="-">Select rating</option><option value="20">Give Syncope and tachycardia 1/5</option><option value="40">Give Syncope and tachycardia 2/5</option><option value="60">Give Syncope and tachycardia 3/5</option><option value="80">Give Syncope and tachycardia 4/5</option><option value="100" selected="selected">Give Syncope and tachycardia 5/5</option></select> <div class="description"><div class="fivestar-summary fivestar-summary-average-count"><span class="average-rating">Average: <span >4.4</span></span> <span class="total-votes">(<span >7</span> votes)</span></div></div> </div> </div> </div><input class="fivestar-submit form-submit" type="submit" id="edit-fivestar-submit--4" name="op" value="Rate" /><input type="hidden" name="form_build_id" value="form-Wevd7OAhoCvyjZ8icrIRwyjEdUWCejVh0UTQgrPqfbM" /> <input type="hidden" name="form_id" value="fivestar_custom_widget" /> </div></form></div></div></div><div class="field field-name-field-taxonomy field-type-taxonomy-term-reference field-label-above"><div class="field-label">Related Terms:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="/ecg/tachycardia" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Tachycardia</a></div><div class="field-item odd"><a href="/ecg/wide-qrs" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Wide QRS</a></div><div class="field-item even"><a href="/ecg/lad" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">LAD</a></div><div class="field-item odd"><a href="/ecg/left-axis-deviation" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left axis deviation</a></div><div class="field-item even"><a href="/ecg/left-anterior-hemiblock" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior hemiblock</a></div><div class="field-item odd"><a href="/ecg/left-anterior-fascicular-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior fascicular block</a></div><div class="field-item even"><a href="/ecg/sinus-tachycardia" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Sinus tachycardia</a></div></div></div><ul class="links inline"><li class="addtoany first last"><span><span class="a2a_kit a2a_target addtoany_list" id="da2a_4"> <a class="a2a_dd addtoany_share_save" href="https://www.addtoany.com/share#url=https%3A%2F%2Fwww.ecgguru.com%2Fecg%2Fsyncope-and-tachycardia&amp;title=Syncope%20and%20tachycardia"><img src="/sites/all/modules/addtoany/images/share_save_256_24.png" width="256" height="24" alt="Share"/></a> </span> </span></li> </ul> Mon, 14 Jan 2019 04:32:51 +0000 Dawn 763 at https://www.ecgguru.com https://www.ecgguru.com/ecg/syncope-and-tachycardia#comments Bifascicular Block https://www.ecgguru.com/ecg/bifascicular-block-0 <div class="field field-name-field-ecg field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/ecg/bifascicular-block-0"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/Bifascicular%20Block.jpg" width="1894" height="677" alt="" /></a></div></div></div><div class="field field-name-field-ecg-interpretation field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p class="MsoNormal"><strong style="mso-bidi-font-weight: normal;"><span style="color: #00b050;">This ECG is from a 77 year old woman&nbsp;</span></strong>who was brought to the Emergency Department by EMS. She was found to be suffering from sepsis.</p><p class="MsoNormal" style="margin-bottom: .0001pt;"><strong style="mso-bidi-font-weight: normal;"><span style="color: #00b050;">ECG Interpretation&nbsp; &nbsp; &nbsp;&nbsp;</span></strong><span style="font-size: 13.008px;">The ECG shows the expected sinus tachycardia at 123 beats per minute.</span><span style="font-size: 13.008px;">&nbsp; </span><span style="font-size: 13.008px;">There is significant baseline artifact, of the type usually seen with muscle tension.</span><span style="font-size: 13.008px;">&nbsp; </span><span style="font-size: 13.008px;">The artifact makes it difficult to assess P waves and PR intervals.</span></p><p class="MsoNormal">&nbsp;</p><p class="MsoNormal">What we do see is <strong style="mso-bidi-font-weight: normal;">RIGHT BUNDLE BRANCH BLOCK</strong> and <strong style="mso-bidi-font-weight: normal;">LEFT ANTERIOR HEMIBLOCK</strong>, also called <strong style="mso-bidi-font-weight: normal;">LEFT</strong> <strong style="mso-bidi-font-weight: normal;">ANTERIOR FASCICULAR BLOCK</strong>.<span style="mso-spacerun: yes;">&nbsp; </span>Together, these are called <strong style="mso-bidi-font-weight: normal;">BIFASCICULAR BLOCK</strong>.<span style="mso-spacerun: yes;">&nbsp; </span>Most people have three main fascicles in the interventricular conduction system:<span style="mso-spacerun: yes;">&nbsp; </span>the right bundle branch and the two branches of the left bundle branch, the anterior-superior fascicle and the posterior-inferior fascicle.<span style="mso-spacerun: yes;">&nbsp; </span>In bifascicular block, two of the three are blocked.</p><p class="MsoNormal" style="margin-bottom: .0001pt;"><strong>The ECG criteria for right bundle branch block are:</strong></p><p class="MsoNormal" style="margin-bottom: .0001pt;"><span style="font-size: 13.008px;">&nbsp; &nbsp; &nbsp;</span><span style="font-size: 13.008px;">*</span><span style="font-size: 13.008px;">&nbsp;&nbsp;&nbsp;&nbsp; </span><span style="font-size: 13.008px;">wide QRS (</span><span style="font-size: 13.008px; text-decoration: underline;">&gt;</span><span style="font-size: 13.008px;">&nbsp;</span><span style="font-size: 13.008px;">.12 seconds)</span></p><p class="MsoNormal" style="margin-bottom: .0001pt; line-height: normal;">&nbsp;</p><p class="MsoNormal" style="margin-bottom: .0001pt; line-height: normal;"><span style="mso-spacerun: yes;">&nbsp;&nbsp;&nbsp;&nbsp; </span>*<span style="mso-spacerun: yes;">&nbsp;&nbsp;&nbsp;&nbsp; </span>rSR’ pattern in V<sub>1 .<span style="mso-spacerun: yes;">&nbsp; </span></sub>(the initial R wave may be hard to see, but the QRS will be predominantly&nbsp;<span style="font-size: 13.008px;">upright.</span></p><p class="MsoNormal" style="margin-bottom: .0001pt; line-height: normal;">&nbsp;</p><p class="MsoNormal" style="margin-bottom: .0001pt; line-height: normal;"><span style="mso-spacerun: yes;">&nbsp;&nbsp;&nbsp;&nbsp; </span>*<span style="mso-spacerun: yes;">&nbsp;&nbsp;&nbsp;&nbsp; </span>wide little S wave in Leads I and V<sub>6</sub>.<span style="font-size: 13.008px;">&nbsp;</span></p><p class="MsoNormal" style="margin-bottom: .0001pt; line-height: normal;"><span style="font-size: 13.008px;"><br /></span></p><p class="MsoNormal" style="margin-bottom: .0001pt; line-height: normal;"><strong>The ECG criteria for left anterior hemiblock are:</strong></p><p class="MsoNormal" style="margin-bottom: .0001pt; line-height: normal;"><span style="mso-spacerun: yes;">&nbsp;&nbsp;&nbsp;&nbsp; </span>*<span style="mso-spacerun: yes;">&nbsp;&nbsp;&nbsp; </span>left axis deviation ( between -45 degrees and -90 degrees)</p><p class="MsoNormal" style="margin-bottom: .0001pt; line-height: normal;"><span style="mso-spacerun: yes;">&nbsp;&nbsp;&nbsp;&nbsp; </span>*<span style="mso-spacerun: yes;">&nbsp;&nbsp;&nbsp; </span>small q waves in Leads I and aVL</p><p class="MsoNormal" style="margin-bottom: .0001pt; line-height: normal;"><span style="mso-spacerun: yes;">&nbsp;&nbsp;&nbsp;&nbsp; </span>*<span style="mso-spacerun: yes;">&nbsp;&nbsp;&nbsp; </span>small r waves with deep S waves in Leads II, III, and aVF.</p><p class="MsoNormal" style="margin-bottom: .0001pt; line-height: normal;"><span style="mso-spacerun: yes;">&nbsp;&nbsp;&nbsp;&nbsp; </span>*<span style="mso-spacerun: yes;">&nbsp;&nbsp;&nbsp; </span>delayed intrinsicoid deflection in aVL (the time between the onset of the QRS and the peak of the&nbsp;<span style="font-size: 13.008px;">R wave is greater than .045 seconds).</span></p><p class="MsoNormal" style="margin-bottom: .0001pt; line-height: normal;">&nbsp;<span style="mso-spacerun: yes;">&nbsp; &nbsp; &nbsp;</span><span style="font-size: 13.008px;">*</span><span style="mso-spacerun: yes;">&nbsp;&nbsp;&nbsp; </span><span style="font-size: 13.008px;">increased voltage in the limb leads may cause aVL to meet voltage criteria for left ventricular&nbsp;</span><span style="font-size: 13.008px;">hypertrophy, but there will be no strain pattern.</span><span style="font-size: 13.008px;">&nbsp;</span></p><p class="MsoNormal" style="margin-bottom: .0001pt; line-height: normal;"><span style="font-size: 13.008px;"><br /></span></p><p class="MsoNormal" style="margin-bottom: .0001pt; line-height: normal;">Other causes of left axis deviation should be ruled out before diagnosing left anterior hemiblock. For example, the pathological Q waves of advanced inferior wall M.I. can cause left axis deviation, as electrical forces diminish in the damaged tissue.</p><p class="MsoNormal" style="margin-bottom: .0001pt; line-height: normal;"><span style="font-size: 13.008px;">Most of this ECG’s J points are at or near the baseline, with some ST depression seen in V</span><sub>2</sub><span style="font-size: 13.008px;"> through V</span><sub>4</sub><span style="font-size: 13.008px;">.</span></p><p class="MsoNormal" style="margin-bottom: .0001pt; line-height: normal;">&nbsp;</p><p class="MsoNormal"><span style="mso-spacerun: yes;">&nbsp;</span><em style="mso-bidi-font-style: normal;"><span style="font-size: 10.0pt; line-height: 107%;">Our thanks to Jonathan Hamilton for donating this ECG</span></em></p></div></div></div><div class="field field-name-field-rate-this-content field-type-fivestar field-label-above"><div class="field-label">Rate this content:&nbsp;</div><div class="field-items"><div class="field-item even"><form class="fivestar-widget" action="/taxonomy/term/42/feed" method="post" id="fivestar-custom-widget--5" accept-charset="UTF-8"><div><div class="clearfix fivestar-average-text fivestar-average-stars fivestar-form-item fivestar-hearts"><div class="form-item form-type-fivestar form-item-vote"> <div class="form-item form-type-select form-item-vote"> <select id="edit-vote--10" name="vote" class="form-select"><option value="-">Select rating</option><option value="20">Give Bifascicular Block 1/5</option><option value="40">Give Bifascicular Block 2/5</option><option value="60">Give Bifascicular Block 3/5</option><option value="80" selected="selected">Give Bifascicular Block 4/5</option><option value="100">Give Bifascicular Block 5/5</option></select> <div class="description"><div class="fivestar-summary fivestar-summary-average-count"><span class="average-rating">Average: <span >4</span></span> <span class="total-votes">(<span >3</span> votes)</span></div></div> </div> </div> </div><input class="fivestar-submit form-submit" type="submit" id="edit-fivestar-submit--5" name="op" value="Rate" /><input type="hidden" name="form_build_id" value="form-1uLuCzzMku2DmTZ7p7lK7kIXBRl63bbf4oU37q1inu0" /> <input type="hidden" name="form_id" value="fivestar_custom_widget" /> </div></form></div></div></div><div class="field field-name-field-taxonomy field-type-taxonomy-term-reference field-label-above"><div class="field-label">Related Terms:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="/ecg/right-bundle-branch-block-1" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Right bundle branch block</a></div><div class="field-item odd"><a href="/ecg/bifascicular-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Bifascicular block</a></div><div class="field-item even"><a href="/ecg/left-anterior-hemiblock" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior hemiblock</a></div><div class="field-item odd"><a href="/ecg/left-anterior-fascicular-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior fascicular block</a></div><div class="field-item even"><a href="/ecg/left-axis-deviation" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left axis deviation</a></div><div class="field-item odd"><a href="/ecg/rbbb" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">RBBB</a></div></div></div><ul class="links inline"><li class="addtoany first last"><span><span class="a2a_kit a2a_target addtoany_list" id="da2a_5"> <a class="a2a_dd addtoany_share_save" href="https://www.addtoany.com/share#url=https%3A%2F%2Fwww.ecgguru.com%2Fecg%2Fbifascicular-block-0&amp;title=Bifascicular%20Block"><img src="/sites/all/modules/addtoany/images/share_save_256_24.png" width="256" height="24" alt="Share"/></a> </span> </span></li> </ul> Fri, 16 Nov 2018 20:35:40 +0000 Dawn 761 at https://www.ecgguru.com https://www.ecgguru.com/ecg/bifascicular-block-0#comments Anterior Wall M.I. With Bifascicular Block https://www.ecgguru.com/ecg/anterior-wall-mi-bifascicular-block-0 <div class="field field-name-field-ecg field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/ecg/anterior-wall-mi-bifascicular-block-0"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/AWMI.jpg" width="1087" height="415" alt="" /></a></div></div></div><div class="field field-name-field-ecg-interpretation field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p class="MsoNormal">This ECG is taken from an 82-year-old man who called 911 because of chest pain.&nbsp; He has an unspecified “cardiac” history, but we do not know the specifics.<span style="font-size: 13.008px;">&nbsp;</span></p><p class="MsoNormal"><strong>WHAT IS THE RHYTHM?&nbsp; </strong>The heart rate is 69 bpm, and there are P waves before every QRS complex. The underlying rhythm is regular, with one premature beat that is wide without a P wave.&nbsp; The PR interval is slightly prolonged at .25 seconds. <strong>&nbsp;The rhythm is normal sinus rhythm with first-degree AV block and one PVC.</strong><strong style="font-size: 13.008px;">&nbsp;</strong></p><p class="MsoNormal"><strong>WHY THE WIDE QRS?&nbsp;&nbsp; </strong>The QRS complex is wide at .14 seconds. The QRS in V 1 has a wide R wave after a small Q wave.&nbsp; This in consistent with <strong>right bundle branch block</strong> pattern, with loss of the normal initial small r wave (pathological Q waves).&nbsp; The diagnosis of RBBB is further corroborated by the wide little S waves in Leads I and V6.&nbsp; The QRS frontal plane axis is -66 degrees per the machine, and clearly “abnormal left” because the QRS in Lead II is negative, while the QRS in Leads I and aVL are positive.&nbsp; This is <strong>left anterior fascicular block</strong>, also called <strong>left anterior hemiblock</strong>.&nbsp; The combination of RBBB and LAFB is a common one, as the two branches have the same blood supply. &nbsp;It is also called <strong>bi-fascicular block</strong>.<span style="font-size: 13.008px;">&nbsp;</span></p><p class="MsoNormal"><strong>WHAT ABOUT THE ST SEGMENTS? &nbsp;</strong><span style="font-size: 13.008px;">The </span><strong style="font-size: 13.008px;">ST segments in leads V2 through V6 are elevated</strong><span style="font-size: 13.008px;">, and their shape is very straight, as opposed to the normal shape of coved upward (smile). Even though the amount of ST elevation at the J points appears subtle, the shape of the segments, the fact that they appear in related leads, and the fact that the patient is an elderly male with chest pain all point to the diagnosis of<strong> ANTERIOR WALL&nbsp;</strong></span><strong style="font-size: 13.008px;">ST elevation M.I. (STEMI).&nbsp; </strong><span style="font-size: 13.008px;">Additional ST changes include a straight shape in Leads I and aVL and ST depression in V1 and aVR.</span><span style="font-size: 13.008px;">&nbsp;</span><span style="font-size: 13.008px;">&nbsp;</span></p><p class="MsoNormal"><strong>PATIENT OUTCOME&nbsp; </strong>The patient was transported to a cardiac center, where he received angioplasty in the cath lab.&nbsp; The left coronary artery was found to be occluded, and was repaired and stented.&nbsp; He recovered without complications and was sent home in a few days.</p></div></div></div><div class="field field-name-field-rate-this-content field-type-fivestar field-label-above"><div class="field-label">Rate this content:&nbsp;</div><div class="field-items"><div class="field-item even"><form class="fivestar-widget" action="/taxonomy/term/42/feed" method="post" id="fivestar-custom-widget--6" accept-charset="UTF-8"><div><div class="clearfix fivestar-average-text fivestar-average-stars fivestar-form-item fivestar-hearts"><div class="form-item form-type-fivestar form-item-vote"> <div class="form-item form-type-select form-item-vote"> <select id="edit-vote--12" name="vote" class="form-select"><option value="-">Select rating</option><option value="20">Give Anterior Wall M.I. With Bifascicular Block 1/5</option><option value="40">Give Anterior Wall M.I. With Bifascicular Block 2/5</option><option value="60">Give Anterior Wall M.I. With Bifascicular Block 3/5</option><option value="80" selected="selected">Give Anterior Wall M.I. With Bifascicular Block 4/5</option><option value="100">Give Anterior Wall M.I. With Bifascicular Block 5/5</option></select> <div class="description"><div class="fivestar-summary fivestar-summary-average-count"><span class="average-rating">Average: <span >3.3</span></span> <span class="total-votes">(<span >6</span> votes)</span></div></div> </div> </div> </div><input class="fivestar-submit form-submit" type="submit" id="edit-fivestar-submit--6" name="op" value="Rate" /><input type="hidden" name="form_build_id" value="form-K_jBfO1p6yCV61TkRD16hVzoeySRgWi8yDMxeEYt_wQ" /> <input type="hidden" name="form_id" value="fivestar_custom_widget" /> </div></form></div></div></div><div class="field field-name-field-taxonomy field-type-taxonomy-term-reference field-label-above"><div class="field-label">Related Terms:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="/ecg/anterior-mi" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Anterior M.I.</a></div><div class="field-item odd"><a href="/ecg/awmi" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">AWMI</a></div><div class="field-item even"><a href="/ecg/right-bundle-branch-block-1" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Right bundle branch block</a></div><div class="field-item odd"><a href="/ecg/rbbb" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">RBBB</a></div><div class="field-item even"><a href="/ecg/left-anterior-fascicular-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior fascicular block</a></div><div class="field-item odd"><a href="/ecg/left-anterior-hemiblock" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior hemiblock</a></div><div class="field-item even"><a href="/ecg/st-elevation" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">ST elevation</a></div><div class="field-item odd"><a href="/ecg/stemi" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">STEMI</a></div><div class="field-item even"><a href="/ecg/pvc" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">PVC</a></div><div class="field-item odd"><a href="/ecg/premature-ventricular-contraction" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Premature ventricular contraction</a></div></div></div><ul class="links inline"><li class="addtoany first last"><span><span class="a2a_kit a2a_target addtoany_list" id="da2a_6"> <a class="a2a_dd addtoany_share_save" href="https://www.addtoany.com/share#url=https%3A%2F%2Fwww.ecgguru.com%2Fecg%2Fanterior-wall-mi-bifascicular-block-0&amp;title=Anterior%20Wall%20M.I.%20With%20Bifascicular%20Block"><img src="/sites/all/modules/addtoany/images/share_save_256_24.png" width="256" height="24" alt="Share"/></a> </span> </span></li> </ul> Sat, 25 Mar 2017 21:13:27 +0000 Dawn 727 at https://www.ecgguru.com https://www.ecgguru.com/ecg/anterior-wall-mi-bifascicular-block-0#comments Bifascicular Block and Sinus Bradycardia https://www.ecgguru.com/ecg/bifascicular-block-and-sinus-bradycardia <div class="field field-name-field-ecg field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/ecg/bifascicular-block-and-sinus-bradycardia"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/RBLAH103%20%20from%20Andrea.jpg" width="1800" height="949" alt="" /></a></div></div></div><div class="field field-name-field-ecg-interpretation field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p class="MsoNormal">Today’s ECG is from a 75 year old man who has been experiencing syncope.<span style="font-size: 8pt;">&nbsp;</span></p><p class="MsoNormal">Examination of the ECG shows a sinus bradycardia at just under 40 bpm.&nbsp; There is a first-degree AV block, with a PR interval of about .28 seconds (280 ms).&nbsp; There is a right bundle branch block.&nbsp; The ECG criteria for right bundle branch block are: &nbsp;supraventricular rhythm, wide QRS (120 ms in this case), rSR’ pattern in V1, and &nbsp;a small, wide S wave in Leads I and V6.&nbsp; There is actually a “terminal delay”, or extra wave at the end of each QRS complex, reflecting late repolarization of the right ventricle.<span style="font-size: 13.008px;">&nbsp;</span></p><p class="MsoNormal">This ECG also shows a left anterior fascicular block, also called left anterior hemiblock.&nbsp; The left bundle branch usually has two main branches, the anterior-superior and the posterior-inferior.&nbsp; ECG criteria for left anterior fascicular block are: left axis deviation with a small r wave in Lead III and a small q waves with tall R waves in Leads I and aVL. &nbsp;There is also a prolonged R wave peak time (&gt; 45 ms) in aVL. There is usually a slightly prolonged QRS, but in this case, there is widening of the QRS due to the RBBB. &nbsp; Because the right bundle branch is blocked, and one fascicle of the left bundle is blocked, the patient is said to have a “bifascicular block”.&nbsp; Only one fascicle remains available for conduction from the atria to the ventricles.</p><p class="MsoNormal">We have no information about what caused the conduction block in these two fascicles, but should the third fascicle fail, the patient will be in a complete AV block.&nbsp; An AV block at the level of the bundle branches will result in an idioventricular escape rhythm – wide QRS complexes with very slow rates – which is a low-output rhythm.<span style="font-size: 13.008px;">&nbsp;</span><span style="font-size: 13.008px;">&nbsp;</span></p><p class="MsoNormal">This patient has also had syncope, which was determined to be related to his bradycardia.&nbsp; He had an AV sequential pacemaker implanted and did well.</p></div></div></div><div class="field field-name-field-rate-this-content field-type-fivestar field-label-above"><div class="field-label">Rate this content:&nbsp;</div><div class="field-items"><div class="field-item even"><form class="fivestar-widget" action="/taxonomy/term/42/feed" method="post" id="fivestar-custom-widget--7" accept-charset="UTF-8"><div><div class="clearfix fivestar-average-text fivestar-average-stars fivestar-form-item fivestar-hearts"><div class="form-item form-type-fivestar form-item-vote"> <div class="form-item form-type-select form-item-vote"> <select id="edit-vote--14" name="vote" class="form-select"><option value="-">Select rating</option><option value="20">Give Bifascicular Block and Sinus Bradycardia 1/5</option><option value="40">Give Bifascicular Block and Sinus Bradycardia 2/5</option><option value="60">Give Bifascicular Block and Sinus Bradycardia 3/5</option><option value="80" selected="selected">Give Bifascicular Block and Sinus Bradycardia 4/5</option><option value="100">Give Bifascicular Block and Sinus Bradycardia 5/5</option></select> <div class="description"><div class="fivestar-summary fivestar-summary-average-count"><span class="average-rating">Average: <span >3.7</span></span> <span class="total-votes">(<span >3</span> votes)</span></div></div> </div> </div> </div><input class="fivestar-submit form-submit" type="submit" id="edit-fivestar-submit--7" name="op" value="Rate" /><input type="hidden" name="form_build_id" value="form-qIBcENp8rorzO0cRBO7MBVlRb5fQcGZFWwppa2HkNy4" /> <input type="hidden" name="form_id" value="fivestar_custom_widget" /> </div></form></div></div></div><div class="field field-name-field-taxonomy field-type-taxonomy-term-reference field-label-above"><div class="field-label">Related Terms:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="/ecg/sinus-bradycardia" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Sinus bradycardia</a></div><div class="field-item odd"><a href="/ecg/bifascicular-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Bifascicular block</a></div><div class="field-item even"><a href="/ecg/left-anterior-hemiblock" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior hemiblock</a></div><div class="field-item odd"><a href="/ecg/rbbb" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">RBBB</a></div><div class="field-item even"><a href="/ecg/st-and-t-wave-changes" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">ST and T wave changes</a></div><div class="field-item odd"><a href="/ecg/left-anterior-fascicular-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior fascicular block</a></div><div class="field-item even"><a href="/ecg/right-bundle-branch-block-1" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Right bundle branch block</a></div></div></div><ul class="links inline"><li class="addtoany first last"><span><span class="a2a_kit a2a_target addtoany_list" id="da2a_7"> <a class="a2a_dd addtoany_share_save" href="https://www.addtoany.com/share#url=https%3A%2F%2Fwww.ecgguru.com%2Fecg%2Fbifascicular-block-and-sinus-bradycardia&amp;title=%20Bifascicular%20Block%20and%20Sinus%20Bradycardia"><img src="/sites/all/modules/addtoany/images/share_save_256_24.png" width="256" height="24" alt="Share"/></a> </span> </span></li> </ul> Sat, 19 Nov 2016 02:30:23 +0000 Dawn 716 at https://www.ecgguru.com https://www.ecgguru.com/ecg/bifascicular-block-and-sinus-bradycardia#comments Teaching Series - Tachycardia and Left Anterior Fascicular Block https://www.ecgguru.com/ecg/teaching-series-tachycardia-and-left-anterior-fascicular-block <div class="field field-name-field-ecg field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/ecg/teaching-series-tachycardia-and-left-anterior-fascicular-block"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/LAH101%20A.jpg" width="1800" height="666" alt="" /></a></div><div class="field-item odd"><a href="/ecg/teaching-series-tachycardia-and-left-anterior-fascicular-block"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/LAH101%20%20-%20B_0.jpg" width="1600" height="1175" alt="" /></a></div><div class="field-item even"><a href="/ecg/teaching-series-tachycardia-and-left-anterior-fascicular-block"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/LAH101%20%20C.jpg" width="1707" height="1309" alt="" /></a></div></div></div><div class="field field-name-field-ecg-interpretation field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p class="MsoNormal"><span style="font-size: 12.0pt; line-height: 107%;">This series of three ECGs is from a 60-year-old man who was brought to the Emergency Department after being involved in a motor vehicle accident.&nbsp; No injuries were found, but the patient was severely intoxicated by alcohol consumption.&nbsp; He was conscious but agitated.</span><span style="font-size: 12pt;">&nbsp;</span></p><p class="MsoNormal"><strong><span style="font-size: 12.0pt; line-height: 107%;">ECG NO. 1&nbsp;&nbsp; &nbsp;&nbsp;15:07:23</span></strong></p><p class="MsoNormal"><span style="font-size: 12.0pt; line-height: 107%;">The first ECG was taken by fire-rescue personnel at the scene of the accident. His hemodynamic status was stable, and the rate was not addressed in the field. ECG No. 1 shows a supraventricular rhythm at 161 bpm, with a narrow QRS and P waves visible before each QRS.</span><span style="font-size: 12pt;">&nbsp;</span></p><p class="MsoNormal"><span style="font-size: 12.0pt; line-height: 107%;">A notable feature of this ECG are the left axis deviation, by default diagnosed at left anterior hemiblock (left anterior fascicular block).&nbsp; The .10 second QRS width is typical of LAHB, as is the rS pattern in Lead III.</span></p><p class="MsoNormal"><span style="font-size: 12.0pt; line-height: 107%;">Also &nbsp;noted is the unusual R wave progression in the precordial leads.&nbsp; The R waves are prominent in V2, and then fail to progress across the precordium, and the S waves persist.&nbsp;</span><span style="font-size: 12pt;">This is probably due to the hemiblock.</span><span style="font-size: 12pt;">&nbsp; </span><span style="font-size: 12pt;">We do not know this patient’s medical history, except that he self-described as an “alcoholic”.</span><span style="font-size: 12pt;">&nbsp; </span><span style="font-size: 12pt;">LAFB can be associated with coronary artery disease.</span><span style="font-size: 12pt;">&nbsp;</span></p><p class="MsoNormal"><strong><span style="font-size: 12.0pt; line-height: 107%;">ECG NO. 2&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;15:20:38</span></strong></p><p class="MsoNormal"><span style="font-size: 12.0pt; line-height: 107%;">Now being evaluated in the Emergency Dept., we see the patient's heart rate is 163 bpm.&nbsp; Some variability in the rate was noted with patient agitation and activity, so it was determined that the rhythm was probably sinus tachycardia.&nbsp; There were no other significant changes in the ECG from the first one.&nbsp; Unfortunately, we no longer have access to lab results, so we do not know his electrolyte or hydration status.&nbsp; Labs confirmed ETOH intoxication.</span><span style="font-size: 12pt;">&nbsp;</span></p><p class="MsoNormal"><strong><span style="font-size: 12.0pt; line-height: 107%;">ECG NO. 3&nbsp; &nbsp;15:43:26</span></strong></p><p class="MsoNormal"><span style="font-size: 12.0pt; line-height: 107%;">After IV fluids and a short rest, the patient is much less agitated, and is conversant.&nbsp; His heart rate is now 105 bpm.&nbsp; This rate was reached by gradual increments, further evidence that this was SINUS TACHYCARDIA all along.&nbsp; Reentrant rhythms (AVNT, AVNRT, atrial flutter) start and stop abruptly.&nbsp; Some leads on ECG No. 3 may suggest an underlying atrial flutter (aVR, aVF), but the waves do not “march out”.</span><span style="font-size: 12pt;">&nbsp;</span></p><p class="MsoNormal"><strong><span style="font-size: 12.0pt; line-height: 107%;">SINUS TACHYCARDIA VS. PSVT</span></strong></p><p class="MsoNormal"><span style="font-size: 12.0pt; line-height: 107%;">At rates over 140 per minute, it can sometimes be difficult to differentiate sinus tach from reentrant tachycardias (PSVT).&nbsp; Seeing gradual adjustments of the rate favors a diagnosis of sinus tach.&nbsp; Also, seeing an obvious “cause” of sinus tach helps.&nbsp; In this case, the patient was a chronic alcohol abuser who was intoxicated.&nbsp; This is associated with sinus tachycardia, due to stimulation of catecholamine secretion and cell membrane alterations.&nbsp; Also, he was agitated and possibly dehydrated.</span></p></div></div></div><div class="field field-name-field-rate-this-content field-type-fivestar field-label-above"><div class="field-label">Rate this content:&nbsp;</div><div class="field-items"><div class="field-item even"><form class="fivestar-widget" action="/taxonomy/term/42/feed" method="post" id="fivestar-custom-widget--8" accept-charset="UTF-8"><div><div class="clearfix fivestar-average-text fivestar-average-stars fivestar-form-item fivestar-hearts"><div class="form-item form-type-fivestar form-item-vote"> <div class="form-item form-type-select form-item-vote"> <select id="edit-vote--16" name="vote" class="form-select"><option value="-">Select rating</option><option value="20">Give Teaching Series - Tachycardia and Left Anterior Fascicular Block 1/5</option><option value="40">Give Teaching Series - Tachycardia and Left Anterior Fascicular Block 2/5</option><option value="60">Give Teaching Series - Tachycardia and Left Anterior Fascicular Block 3/5</option><option value="80" selected="selected">Give Teaching Series - Tachycardia and Left Anterior Fascicular Block 4/5</option><option value="100">Give Teaching Series - Tachycardia and Left Anterior Fascicular Block 5/5</option></select> <div class="description"><div class="fivestar-summary fivestar-summary-average-count"><span class="average-rating">Average: <span >3.1</span></span> <span class="total-votes">(<span >11</span> votes)</span></div></div> </div> </div> </div><input class="fivestar-submit form-submit" type="submit" id="edit-fivestar-submit--8" name="op" value="Rate" /><input type="hidden" name="form_build_id" value="form-FX_027rYvnGdttNYpDuL752rIgaMEMuVSIYPbifxIHc" /> <input type="hidden" name="form_id" value="fivestar_custom_widget" /> </div></form></div></div></div><div class="field field-name-field-taxonomy field-type-taxonomy-term-reference field-label-above"><div class="field-label">Related Terms:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="/ecg/sinus-tachycardia" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Sinus tachycardia</a></div><div class="field-item odd"><a href="/ecg/supraventricular-tachycardia" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Supraventricular tachycardia</a></div><div class="field-item even"><a href="/ecg/psvt" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">PSVT</a></div><div class="field-item odd"><a href="/ecg/teaching-series" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Teaching series</a></div><div class="field-item even"><a href="/ecg/left-anterior-fascicular-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior fascicular block</a></div><div class="field-item odd"><a href="/ecg/left-anterior-hemiblock" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior hemiblock</a></div><div class="field-item even"><a href="/ecg/poor-r-wave-progression-0" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Poor R wave progression</a></div></div></div><ul class="links inline"><li class="addtoany first last"><span><span class="a2a_kit a2a_target addtoany_list" id="da2a_8"> <a class="a2a_dd addtoany_share_save" href="https://www.addtoany.com/share#url=https%3A%2F%2Fwww.ecgguru.com%2Fecg%2Fteaching-series-tachycardia-and-left-anterior-fascicular-block&amp;title=Teaching%20Series%20-%20Tachycardia%20and%20Left%20Anterior%20Fascicular%20Block"><img src="/sites/all/modules/addtoany/images/share_save_256_24.png" width="256" height="24" alt="Share"/></a> </span> </span></li> </ul> Sat, 15 Oct 2016 21:48:02 +0000 Dawn 712 at https://www.ecgguru.com https://www.ecgguru.com/ecg/teaching-series-tachycardia-and-left-anterior-fascicular-block#comments Subtle ST Elevation And Left Anterior Hemiblock https://www.ecgguru.com/ecg/subtle-st-elevation-and-left-anterior-hemiblock <div class="field field-name-field-ecg field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/ecg/subtle-st-elevation-and-left-anterior-hemiblock"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/CAD%20108%20Crew%20CAlert%20Downgr%20by%20ED.jpg" width="1800" height="559" alt="" /></a></div></div></div><div class="field field-name-field-ecg-interpretation field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p class="MsoNormal">We have no clinical information about this patient, except that he was complaining of chest pain, and was initially treated by prehospital paramedics.</p><p class="MsoNormal"><strong>ST Changes &nbsp; &nbsp; &nbsp;</strong><span style="font-size: 13.008px; line-height: 1.538em;">The paramedics noted a slight J point elevation in the precordial leads, specifically about one mm of elevation in Leads V2, V3, and V4.&nbsp; In addition, the ST segments are curved downward like a frown in V1 and straight in the remaining precordial leads. Because of the patient’s symptoms, and the ST abnormalities, they notified the hospital that they believed this was a STEMI.&nbsp; The patient was transported without complications, and the Emergency Department physician subsequently downgraded the initial assessment of STEMI Alert.&nbsp; We do not have access to follow up.&nbsp;</span><span style="font-size: 13.008px; line-height: 1.538em;">These ST segments are abnormal, but do not necessarily indicate an acute ST-elevation M.I. (STEMI). A flat or “frowning” ST segment DOES suggest coronary artery disease, and the patient’s symptoms are worrisome.</span><span style="font-size: 13.008px; line-height: 1.538em;">&nbsp; </span><span style="font-size: 13.008px; line-height: 1.538em;">However, before activating the cath lab emergently, it is sometimes preferable to observe the patient, check cardiac enzymes and other lab results, and repeat ECGs.</span><span style="font-size: 13.008px; line-height: 1.538em;">&nbsp;</span></p><p class="MsoNormal">&nbsp;</p><p class="MsoNormal"><strong>Are These ST Changes Due to Acute M.I.?</strong> &nbsp; There are several accepted <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4209433/">guidelines</a> in use for evaluating ST segments for STEMI.&nbsp; Some are simplified for ease of use, and some are very detailed, taking into consideration the patient’s age and gender. There are ECG features that INCREASE the chances of ST elevation being due to acute M.I. &nbsp;These features include:</p><p class="MsoListParagraphCxSpFirst" style="margin-left: .75in; mso-add-space: auto; text-indent: -.25in; mso-list: l0 level1 lfo1;"><!--[if !supportLists]--><span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;">·<span style="font-stretch: normal; font-size: 7pt; line-height: normal; font-family: 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span><!--[endif]-->ST elevations are in related leads</p><p class="MsoListParagraphCxSpFirst" style="margin-left: .75in; mso-add-space: auto; text-indent: -.25in; mso-list: l0 level1 lfo1;"><span style="text-indent: -0.25in; font-size: 13.008px; line-height: 1.538em; font-family: Symbol;">·<span style="font-stretch: normal; font-size: 7pt; line-height: normal; font-family: 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span><span style="text-indent: -0.25in; font-size: 13.008px; line-height: 1.538em;">ST segments are flat or convex upward (frowning)</span><span style="text-indent: -0.25in; font-size: 13.008px; line-height: 1.538em;">&nbsp;</span></p><p class="MsoListParagraphCxSpMiddle" style="margin-left: .75in; mso-add-space: auto; text-indent: -.25in; mso-list: l0 level1 lfo1;"><!--[if !supportLists]--><span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;">·<span style="font-stretch: normal; font-size: 7pt; line-height: normal; font-family: 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span><!--[endif]-->There are reciprocal ST depressions</p><p class="MsoListParagraphCxSpMiddle" style="margin-left: .75in; mso-add-space: auto; text-indent: -.25in; mso-list: l0 level1 lfo1;"><!--[if !supportLists]--><span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;">·<span style="font-stretch: normal; font-size: 7pt; line-height: normal; font-family: 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span><!--[endif]-->There are associated ECG signs of M.I. such as pathological Q waves and inverted T waves</p><p class="MsoListParagraphCxSpLast" style="margin-left: .75in; mso-add-space: auto; text-indent: -.25in; mso-list: l0 level1 lfo1;"><!--[if !supportLists]--><span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;">·<span style="font-stretch: normal; font-size: 7pt; line-height: normal; font-family: 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span><!--[endif]-->J points are higher than 1 mm (females have less STE requirement for M.I. diagnosis)&nbsp;&nbsp; Leads V2 and V3 generally require 2 mm of STE for a STEMI diagnosis.</p><p class="MsoListParagraphCxSpLast" style="margin-left: .75in; mso-add-space: auto; text-indent: -.25in; mso-list: l0 level1 lfo1;">As we evaluate this ECG, we see that the subtle ST elevations are in related leads (V1 - V3). &nbsp;They are flat (V2 and V3) &nbsp;or convex (V1). &nbsp;There is NO reciprocal depression of the ST segments. &nbsp;There are NO pathological Q waves. T waves are inverted in V1 and flat in Lead III, a non-specific finding. &nbsp;And the J points are minimally elevated at 1 mm or less. By most standard protocols, this ECG does not meet the criteria for acute STEMI. &nbsp;This does NOT rule out the possibility of M.I.</p><p class="MsoNormal"><strong>Other Considerations</strong> &nbsp; &nbsp;It is worth noting that strictly “normal” R wave progression is not seen in this ECG.&nbsp; Leads V2 through V6 show normal R wave progression.&nbsp; That is, the R waves progressively become proportionately larger, while the S waves regress.&nbsp; V1, however, does not have the morphology expected, a small r wave and a deep S wave. We are not sure if this is a lead placement issue or not.&nbsp; When V1 has abnormalities not shared by V2, we sometimes see similar changes in Lead III, because V1 and Lead III are both oriented toward the heart’s right side.&nbsp; In this ECG, Lead III does not resemble Lead V1.&nbsp; Also, there is a left axis deviation.&nbsp; If no other cause for left axis deviation is readily apparent, the cause is presumed to be <span style="color: #0070c0;"><a href="http://lifeinthefastlane.com/ecg-library/basics/left-anterior-fascicular-block/">LEFT ANTERIOR HEMIBLOCK</a></span>, also called left anterior fascicular block.&nbsp; LAH is sometimes caused by anterior-septal M.I., with an incidence of about 7-15%.<span style="font-size: 13.008px; line-height: 1.538em;">&nbsp;</span></p><p class="MsoNormal">Ref.:<a href="http://journal.publications.chestnet.org/solr/searchresults.aspx?q=Marriott&amp;allJournals=1&amp;restypeid=3"> <span style="font-size: 9.5pt; line-height: 107%; font-family: inherit, serif; border: 1pt none windowtext; padding: 0in;">Marriott HJL, Hogan RN. Hemiblock in acute myocardial infarction.&nbsp;<em>Chest.</em>1970;&nbsp;58:&nbsp;342–344.</span></a></p></div></div></div><div class="field field-name-field-rate-this-content field-type-fivestar field-label-above"><div class="field-label">Rate this content:&nbsp;</div><div class="field-items"><div class="field-item even"><form class="fivestar-widget" action="/taxonomy/term/42/feed" method="post" id="fivestar-custom-widget--9" accept-charset="UTF-8"><div><div class="clearfix fivestar-average-text fivestar-average-stars fivestar-form-item fivestar-hearts"><div class="form-item form-type-fivestar form-item-vote"> <div class="form-item form-type-select form-item-vote"> <select id="edit-vote--18" name="vote" class="form-select"><option value="-">Select rating</option><option value="20">Give Subtle ST Elevation And Left Anterior Hemiblock 1/5</option><option value="40">Give Subtle ST Elevation And Left Anterior Hemiblock 2/5</option><option value="60">Give Subtle ST Elevation And Left Anterior Hemiblock 3/5</option><option value="80">Give Subtle ST Elevation And Left Anterior Hemiblock 4/5</option><option value="100" selected="selected">Give Subtle ST Elevation And Left Anterior Hemiblock 5/5</option></select> <div class="description"><div class="fivestar-summary fivestar-summary-average-count"><span class="average-rating">Average: <span >4.3</span></span> <span class="total-votes">(<span >3</span> votes)</span></div></div> </div> </div> </div><input class="fivestar-submit form-submit" type="submit" id="edit-fivestar-submit--9" name="op" value="Rate" /><input type="hidden" name="form_build_id" value="form-9ifD3IWCXcwwvZDybfJMW4jye-JPht4qWhm5WRzLpVU" /> <input type="hidden" name="form_id" value="fivestar_custom_widget" /> </div></form></div></div></div><div class="field field-name-field-taxonomy field-type-taxonomy-term-reference field-label-above"><div class="field-label">Related Terms:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="/ecg/left-anterior-hemiblock" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior hemiblock</a></div><div class="field-item odd"><a href="/ecg/left-anterior-fascicular-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior fascicular block</a></div><div class="field-item even"><a href="/ecg/st-elevation" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">ST elevation</a></div><div class="field-item odd"><a href="/ecg/coronary-artery-disease-0" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Coronary artery disease</a></div></div></div><ul class="links inline"><li class="addtoany first last"><span><span class="a2a_kit a2a_target addtoany_list" id="da2a_9"> <a class="a2a_dd addtoany_share_save" href="https://www.addtoany.com/share#url=https%3A%2F%2Fwww.ecgguru.com%2Fecg%2Fsubtle-st-elevation-and-left-anterior-hemiblock&amp;title=Subtle%20ST%20Elevation%20And%20Left%20Anterior%20Hemiblock"><img src="/sites/all/modules/addtoany/images/share_save_256_24.png" width="256" height="24" alt="Share"/></a> </span> </span></li> </ul> Mon, 01 Feb 2016 05:11:50 +0000 Dawn 685 at https://www.ecgguru.com https://www.ecgguru.com/ecg/subtle-st-elevation-and-left-anterior-hemiblock#comments Left Anterior Fascicular Block (Hemiblock) https://www.ecgguru.com/ecg/instructors-collection-ecg-week-september-13-2015-left-anterior-fascicular-block-hemiblock-0 <div class="field field-name-field-ecg field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/ecg/instructors-collection-ecg-week-september-13-2015-left-anterior-fascicular-block-hemiblock-0"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/LAH100_1.jpg" width="1800" height="867" alt="" /></a></div></div></div><div class="field field-name-field-ecg-interpretation field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p style="font-size: 13.008px; line-height: 20.0063px;">This ECG provides an example of LEFT ANTERIOR FASCICULAR BLOCK (LAFB). &nbsp;It is from a 71-year-old woman for whom we have no other history. &nbsp;She also has first-degree AV block and right bundle branch block. &nbsp;RBBB and LAFB together are called bifascicular block. &nbsp;It is not uncommon to see this type of bifascicular block, as the right bundle branch and the &nbsp;anterior fascicle of the left bundle share a blood supply.<span style="font-size: 13.008px; line-height: 20.0063px;">&nbsp;</span></p><p style="font-size: 13.008px; line-height: 20.0063px;">The conduction system below the AV node consists of the Bundle of His, the left bundle branch, and the right bundle branch. &nbsp;While there is some variation among individuals, most of us have two main fascicles, or branches, of the left bundle. &nbsp;The ANTERIOR-SUPERIOR fascicle carries the electrical impulse to the anterior wall of the left ventricle, and the POSTERIOR - INFERIOR fascicle carries the impulse to the inferior area of the left ventricle.</p><p style="font-size: 13.008px; line-height: 20.0063px;">Blocks can occur at any level in the conduction system, including left bundle branch block, right bundle branch block, left anterior fascicular block, left posterior block, and bi-fascicular blocks. LAFB can have many causes, including myocardial infarction, cardiomyopathies, fibrosis of the cartilagenous ring, and aortic valve disease. &nbsp;Left anterior fascicular block is much more common than left posterior fascicular block. Both are also called hemiblocks.</p><p style="font-size: 13.008px; line-height: 20.0063px;">When LAFB is present, the initial septal depolarization forces are still left to right, providing a small initial q wave in Lead I and a small r wave in Lead III. &nbsp;After septal depolarization is complete, the activation vector moves inferiorly and to the right as the electrical wavefront moves through the left posterior hemifascicle and right bundle branch. The impulse finally makes its way to the left and superiorly via slow conduction through myocardium normally depolarized by the left anterior hemifascicle, which is blocked. &nbsp;It is because the terminal left ventricular activation moves upward and toward the left that the &nbsp;inferior leads have negative deflections.</p><p style="font-size: 13.008px; line-height: 20.0063px;">The diagnostic criteria for LAFB are: &nbsp;LEFT AXIS DEVIATION (QRS axis between -45 degrees and -90 degrees); qR pattern in Lead I; rS pattern in Lead III; delayed activation time evident in Lead aVL - the time from onset of the QRS to the peak of the R wave is 45 ms or more. (This example barely makes that criteria, and it is difficult to measure due to the poor copy quality); QRS duration normal or slightly wide, but not 120 ms or more (unless there is also RBBB). &nbsp;LAFB also causes poor R wave progression in the precordial leads, with late transition and S wave present in V6.</p><p style="font-size: 13.008px; line-height: 20.0063px;">Before deciding on a diagnosis of LAFB, you must rule out previous or acute INFERIOR WALL M.I. &nbsp;The pathological Q waves that can occur with necrosis can cause a left axis deviation in the frontal plane. &nbsp;The presence of a small r wave in Lead III rules out pathological Q wave in that lead. &nbsp;If any fascicular block (hemiblock or bundle branch block) occurs during the course of an M.I., the patient should be watched carefully for progression of the block. &nbsp;Be prepared to pace if necessary in that situation.&nbsp;</p><p style="font-size: 13.008px; line-height: 20.0063px;">For more information on hemiblocks, check <a title="Grauer ECG Blog 90" href="http://ecg-interpretation.blogspot.com/2014/06/ecg-blog-90-basic-concepts-3.html">Dr. Ken Grauer's ECG Blog #90 - Basic Concepts-3</a>, and also his video on <a title="Grauer Axis Hemiblocks Video" href="http://www.axisecg.com/">hemiblocks and axis</a>.</p></div></div></div><div class="field field-name-field-rate-this-content field-type-fivestar field-label-above"><div class="field-label">Rate this content:&nbsp;</div><div class="field-items"><div class="field-item even"><form class="fivestar-widget" action="/taxonomy/term/42/feed" method="post" id="fivestar-custom-widget--10" accept-charset="UTF-8"><div><div class="clearfix fivestar-average-text fivestar-average-stars fivestar-form-item fivestar-hearts"><div class="form-item form-type-fivestar form-item-vote"> <div class="form-item form-type-select form-item-vote"> <select id="edit-vote--20" name="vote" class="form-select"><option value="-">Select rating</option><option value="20">Give Left Anterior Fascicular Block (Hemiblock) 1/5</option><option value="40">Give Left Anterior Fascicular Block (Hemiblock) 2/5</option><option value="60">Give Left Anterior Fascicular Block (Hemiblock) 3/5</option><option value="80">Give Left Anterior Fascicular Block (Hemiblock) 4/5</option><option value="100" selected="selected">Give Left Anterior Fascicular Block (Hemiblock) 5/5</option></select> <div class="description"><div class="fivestar-summary fivestar-summary-average-count"><span class="average-rating">Average: <span >5</span></span> <span class="total-votes">(<span >1</span> vote)</span></div></div> </div> </div> </div><input class="fivestar-submit form-submit" type="submit" id="edit-fivestar-submit--10" name="op" value="Rate" /><input type="hidden" name="form_build_id" value="form-rlV4csIER2u-AtnvTGIgDgV5aBERMSznNi-KyA6jzbE" /> <input type="hidden" name="form_id" value="fivestar_custom_widget" /> </div></form></div></div></div><div class="field field-name-field-taxonomy field-type-taxonomy-term-reference field-label-above"><div class="field-label">Related Terms:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="/ecg/left-anterior-fascicular-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior fascicular block</a></div><div class="field-item odd"><a href="/ecg/fascicular-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Fascicular block</a></div><div class="field-item even"><a href="/ecg/left-anterior-hemiblock" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left anterior hemiblock</a></div><div class="field-item odd"><a href="/ecg/hemiblock" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Hemiblock</a></div></div></div><ul class="links inline"><li class="addtoany first last"><span><span class="a2a_kit a2a_target addtoany_list" id="da2a_10"> <a class="a2a_dd addtoany_share_save" href="https://www.addtoany.com/share#url=https%3A%2F%2Fwww.ecgguru.com%2Fecg%2Finstructors-collection-ecg-week-september-13-2015-left-anterior-fascicular-block-hemiblock-0&amp;title=Left%20Anterior%20Fascicular%20Block%20%28Hemiblock%29"><img src="/sites/all/modules/addtoany/images/share_save_256_24.png" width="256" height="24" alt="Share"/></a> </span> </span></li> </ul> Mon, 14 Sep 2015 04:10:17 +0000 Dawn 665 at https://www.ecgguru.com https://www.ecgguru.com/ecg/instructors-collection-ecg-week-september-13-2015-left-anterior-fascicular-block-hemiblock-0#comments