ECG Guru - Instructor Resources - Bundle branch block https://www.ecgguru.com/ecg/bundle-branch-block en Left Bundle Branch Block https://www.ecgguru.com/ecg/left-bundle-branch-block-4 <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/left-bundle-branch-block-4"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/LB119.jpg" width="1800" height="1322" alt="" /></a></div><div class="field-item odd"><a href="/ecg/left-bundle-branch-block-4"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/LB119%20Lead%20II%20P%20wave.jpg" width="152" height="137" alt="" /></a></div><div class="field-item even"><a href="/ecg/left-bundle-branch-block-4"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/LB119%20Lead%20V1%20P%20wave.jpg" width="211" height="226" 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 elderly man with heart failure.<span style="mso-spacerun: yes;">&nbsp; </span></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></strong>The first feature that might capture your attention is the wider-than-normal QRS complex, which is 160 ms (.16 seconds).<span style="mso-spacerun: yes;">&nbsp; </span>The rate is 58 bpm. We do not know the patient’s medications or baseline rate.<span style="mso-spacerun: yes;">&nbsp; </span>There are P waves present, and so the rhythm is <strong>SINUS BRADYCARDIA. </strong>The P waves are broad , &gt; 110 ms in Lead II (red lines in close up) and bifid, with greater than 40 ms between the two peaks in Lead II (blue lines).<span style="mso-spacerun: yes;">&nbsp; </span>In V1, the P waves are biphasic, with the terminal negative portion greater than 40 ms duration (red lines). This meets the ECG criteria for <strong>LEFT ATRIAL ENLARGEMENT, or preferably, LEFT ATRIAL ABNORMALITY</strong>. (<a href="https://litfl.com/left-atrial-enlargement-ecg-library/">https://LITFL.com/left-atrial-enlargement-ecg-library/</a>) ECG criteria are not highly accurate for detecting atrial enlargement, and abnormal findings should be confirmed by anatomic measurement. (<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2244611/">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2244611/</a>).</p><p class="MsoNormal">The QRS complexes, as mentioned, are wide. Because there is sinus rhythm, we know the delay in conduction is due to interventricular conduction delay, and not to ventricular rhythm.<span style="mso-spacerun: yes;">&nbsp; </span>This ECG meets the criteria for <strong>LEFT BUNDLE BRANCH BLOCK.<span style="mso-spacerun: yes;">&nbsp; </span></strong></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; mso-bidi-font-weight: bold;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span></span><!--[endif]-->Supraventricular rhythm<span style="mso-spacerun: yes;">&nbsp; </span><strong></strong></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; mso-bidi-font-weight: bold;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span></span><!--[endif]-->Wide QRS (<span style="text-decoration: underline;">&gt;</span>.12 seconds)<strong></strong></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; mso-bidi-font-weight: bold;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span></span><!--[endif]-->Upright QRS in Leads I and V6<strong></strong></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; mso-bidi-font-weight: bold;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span></span><!--[endif]-->Negative QRS in Lead V1.<strong></strong></p><p class="MsoNormal">Both left atrial abnormalities and left bundle branch are associated with &nbsp;heart failure. The leftward axis at -39 degrees is commonly seen with left bundle branch block.</p><p class="MsoNormal">The ST segment elevation in V1 through V4 is normally seen in LBBB.<span style="mso-spacerun: yes;">&nbsp; </span>The amount of elevation will be associated with the depth of the negative QRS complex.<span style="mso-spacerun: yes;">&nbsp; </span>That is, the deeper the QRS, the higher the STE will be.<span style="mso-spacerun: yes;">&nbsp; </span>ST segments and T wave size and shape can be altered by LBBB.<span style="mso-spacerun: yes;">&nbsp; </span>If a patient with LBBB has symptoms of acute coronary insufficiency, further evaluation is warranted.<span style="mso-spacerun: yes;">&nbsp; </span>On the topic of LBBB and acute M.I., the <a href="https://wikem.org/wiki/Sgarbossa%27s_criteria">Smith-Modified Sgarbossa Criteria</a> should be reviewed, as it is one of the most accurate predictors of acute coronary occlusion in the patient with LBBB.</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/222/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 Left Bundle Branch Block 1/5</option><option value="40">Give Left Bundle Branch Block 2/5</option><option value="60">Give Left Bundle Branch Block 3/5</option><option value="80" selected="selected">Give Left Bundle Branch Block 4/5</option><option value="100">Give Left Bundle Branch 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 >69</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-yALymkEqfVmB-F0vZDwp__jPxWOUjO4nCCuy-qqchuk" /> <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-bundle-branch-block-0" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left bundle branch block</a></div><div class="field-item odd"><a href="/ecg/lbbb" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">LBBB</a></div><div class="field-item even"><a href="/ecg/p-mitrale" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">P mitrale</a></div><div class="field-item odd"><a href="/ecg/left-atrial-abnormality" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left atrial abnormality</a></div><div class="field-item even"><a href="/ecg/left-atrial-enlargement" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left atrial enlargement</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/smith-modified-sgarbossa-criteria-0" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Smith-modified Sgarbossa Criteria</a></div><div class="field-item odd"><a href="/ecg/bundle-branch-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">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_1"> <a class="a2a_dd addtoany_share_save" href="https://www.addtoany.com/share#url=https%3A%2F%2Fwww.ecgguru.com%2Fecg%2Fleft-bundle-branch-block-4&amp;title=Left%20Bundle%20Branch%20Block"><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> Thu, 12 Aug 2021 21:08:19 +0000 Dawn 799 at https://www.ecgguru.com https://www.ecgguru.com/ecg/left-bundle-branch-block-4#comments Right Bundle Branch Block https://www.ecgguru.com/ecg/instructors-collection-ecg-week-september-23-2015-right-bundle-branch-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/instructors-collection-ecg-week-september-23-2015-right-bundle-branch-block-0"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/RB109.jpg" width="1800" height="1469" 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>This ECG is from a 59-year-old man who was a patient in the Emergency Department with mild chest pain. &nbsp;He had a history of coronary artery disease. &nbsp;We have no other information about his medical history, medications, or outcome.</p><p>The ECG shows normal sinus rhythm and right bundle branch block. &nbsp;The ECG criteria for right bundle branch block are: 1) &nbsp;QRS wide at 120 ms or more (.12 sec. or more). &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 2) Supraventricular rhythm. &nbsp; &nbsp; 3) Terminal waves indicating that the right ventricle is depolarizing late. &nbsp;Because the right bundle branch is blocked, the left ventricle depolarizes first. &nbsp;The QRS begins in a normal fashion. &nbsp;The depolarization wave cannot access the right ventricle via the bundle branch, so it travels cell-to-cell across the right ventricle, causing a conduction delay. &nbsp;This delay in depolarizing the right ventricle is seen on the ECG as a separate, terminal wave on the QRS. &nbsp;In V1, it is seen as an R' wave, making the QRS have an rSR' pattern in most cases. &nbsp;In Leads I and V6, there will be a wide, slurred S wave, causing an Rs pattern. &nbsp;The frontal plane axis can be difficult to determine, as the first part of the QRS is from the left ventricle and the second part is from the right ventricle.</p><p>The causes of right bundle branch block are many. &nbsp;The website, <a title="LITFL RBBB" href="http://lifeinthefastlane.com/ecg-library/basics/right-bundle-branch-block/">Life In the Fastlane</a> has a good quick reference.&nbsp;</p><p>This patient has a slightly prolonged QTc interval at 469 ms, for which we do not know the reason, lacking clinical information. &nbsp;The QT interval measures the total time it takes to depolarize and repolarize the myocardium, and it is measured from the beginning of the QRS to the end of the T wave. &nbsp;The QT interval lengthens naturally in slow rates, and shortens with faster rates. &nbsp;The QTc has been mathematically corrected to a rate of 60/min. &nbsp; A good rule of thumb is the QT interval should be less than half the RR interval of the preceding beat. A long QT interval (&gt;500 ms) has been associated with increased risk of <a title="ECG Guru TDP" href="http://www.ecgguru.com/ecg-basics-torsades-de-pointes">torsades de pointes</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/222/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 Right Bundle Branch Block 1/5</option><option value="40">Give Right Bundle Branch Block 2/5</option><option value="60" selected="selected">Give Right Bundle Branch Block 3/5</option><option value="80">Give Right Bundle Branch Block 4/5</option><option value="100">Give Right Bundle Branch Block 5/5</option></select> <div class="description"><div class="fivestar-summary fivestar-summary-average-count"><span class="average-rating">Average: <span >2.8</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--2" name="op" value="Rate" /><input type="hidden" name="form_build_id" value="form-Qy6of_mf2F974vK5TvI_kuY4yhrUOjRoHpi9Mcr1UbQ" /> <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/rbbb" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">RBBB</a></div><div class="field-item even"><a href="/ecg/bundle-branch-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Bundle branch block</a></div><div class="field-item odd"><a href="/ecg/long-qt" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Long QT</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%2Finstructors-collection-ecg-week-september-23-2015-right-bundle-branch-block-0&amp;title=Right%20Bundle%20Branch%20Block"><img src="/sites/all/modules/addtoany/images/share_save_256_24.png" width="256" height="24" alt="Share"/></a> </span> </span></li> </ul> Thu, 24 Sep 2015 04:14:00 +0000 Dawn 667 at https://www.ecgguru.com https://www.ecgguru.com/ecg/instructors-collection-ecg-week-september-23-2015-right-bundle-branch-block-0#comments Second-degree AV Block with 2:1 Conduction and Right Bundle Branch Block https://www.ecgguru.com/ecg/second-degree-av-block-21-conduction-and-right-bundle-branch-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/second-degree-av-block-21-conduction-and-right-bundle-branch-block"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/RBAVB100_0.jpg" width="1591" height="1207" 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="margin-top: 0px; margin-bottom: 20px; outline: 0px; font-family: Verdana, Helvetica, Arial, sans-serif; font-size: 13px; font-stretch: inherit; line-height: 17.7272720336914px; clear: left;">This interesting ECG is a great one for your more advanced students who are ready to discuss the anatomical and physiological differences between the AV blocks, as opposed to just measuring PR intervals. &nbsp;It shows a sinus rhythm with an atrial rate of 72/minute.&nbsp; Second-degree AV block causes every other p wave to be blocked, resulting in a pulse rate of 36 beats per minute.&nbsp; In addition, the ECG shows right bundle branch block, as evidenced by the wide QRS (136 ms), rsR'&nbsp;pattern in V1, and the wide little S wave in Lead I.</p><p style="margin-top: 0px; margin-bottom: 20px; outline: 0px; font-family: Verdana, Helvetica, Arial, sans-serif; font-size: 13px; font-stretch: inherit; line-height: 17.7272720336914px; clear: left;"><span style="line-height: 17.7272720336914px;">When second-degree AVB conducts 2:1, it can sometimes be difficult to determine if the block is Type I (occuring above the Bundle of His), or Type II (occuring at or below the Bundle of His).&nbsp; This is because two p waves must be conducted in a row to see the tell-tale progressive prolongation of the PR interval seen in&nbsp;Type I (Wenkebach).</span></p><p style="margin-top: 0px; margin-bottom: 20px; outline: 0px; font-family: Verdana, Helvetica, Arial, sans-serif; font-size: 13px; font-stretch: inherit; line-height: 17.7272720336914px; clear: left;">Two&nbsp;clues that this block is Type II are:&nbsp; 1) the presence of right bundle branch block.&nbsp; Type II blocks are sub-Hisian blocks, often in the fascicles, and the right bundle branch block is a fascicle block.&nbsp; Many Type II AV blocks show signs of right bundle branch block; &nbsp; 2) The non-conducted p waves occur well clear of the refractory periods of the preceding beats.&nbsp; In Type I blocks, the QRS is eventually dropped because the&nbsp;p wave occurs in the refractory beat of the preceding QRS. Only one beat is missed.&nbsp; In Type II blocks, p waves that SHOULD have conducted, don't.&nbsp; Sometimes, more than one p wave in a row will be non-conducted.</p><p style="margin-top: 0px; margin-bottom: 20px; outline: 0px; font-family: Verdana, Helvetica, Arial, sans-serif; font-size: 13px; font-stretch: inherit; line-height: 17.7272720336914px; clear: left;">Clinically, we would need to be concerned about the location of the block, because supra-Hisian blocks can be transient or even benign, and sub-Hisian blocks are often permanent or progressive. &nbsp;But the most immediate concern, of course, is that the patient's heart rate has been halved, resulting in a bradycardia which is almost certainly symptomatic. &nbsp;Also, we would want to evaluate the patient for coronary artery disease and M.I., as that could be the cause of the AV block. This patient has some minor flattening of the ST segments in Lead III, but the T wave inversion can be explained by the RBBB. &nbsp;Unfortunately, we do not have clinical information on this patient.</p><div>&nbsp;</div></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/222/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 Second-degree AV Block with 2:1 Conduction and Right Bundle Branch Block 1/5</option><option value="40">Give Second-degree AV Block with 2:1 Conduction and Right Bundle Branch Block 2/5</option><option value="60">Give Second-degree AV Block with 2:1 Conduction and Right Bundle Branch Block 3/5</option><option value="80" selected="selected">Give Second-degree AV Block with 2:1 Conduction and Right Bundle Branch Block 4/5</option><option value="100">Give Second-degree AV Block with 2:1 Conduction and Right Bundle Branch Block 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 >4</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-0QdQx2Mub8hxXe-86USwLy3D86O-YenBW1lPzrctkzw" /> <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/av-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">AV Block</a></div><div class="field-item odd"><a href="/ecg/21-av-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">2:1 AV block</a></div><div class="field-item even"><a href="/ecg/rbbb" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">RBBB</a></div><div class="field-item odd"><a href="/ecg/bundle-branch-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Bundle branch block</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/second-degree-av-block-21-conduction" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Second-degree AV block with 2:1 conduction</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%2Fsecond-degree-av-block-21-conduction-and-right-bundle-branch-block&amp;title=Second-degree%20AV%20Block%20with%202%3A1%20Conduction%20and%20Right%20Bundle%20Branch%20Block"><img src="/sites/all/modules/addtoany/images/share_save_256_24.png" width="256" height="24" alt="Share"/></a> </span> </span></li> </ul> Tue, 03 Mar 2015 05:19:11 +0000 Dawn 626 at https://www.ecgguru.com https://www.ecgguru.com/ecg/second-degree-av-block-21-conduction-and-right-bundle-branch-block#comments Left Bundle Branch Block https://www.ecgguru.com/ecg/left-bundle-branch-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/left-bundle-branch-block"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/LB102.jpg" width="1800" height="711" 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-family: 'Arial',sans-serif;">This ECG shows a “classic” left bundle branch block pattern.</span><span style="font-family: Arial, sans-serif; font-size: 13.0080003738403px; line-height: 1.538em;">&nbsp;</span></p><p class="MsoNormal"><span style="font-family: 'Arial',sans-serif;">The ECG criteria for left bundle branch block are:</span></p><p class="MsoNormal"><span style="text-indent: -0.25in; font-size: 13.0080003738403px; 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: 13.0080003738403px; line-height: 1.538em; font-family: Arial, sans-serif;">Wide QRS (.12 seconds or greater)</span></p><p class="MsoNormal"><span style="text-indent: -0.25in; font-size: 13.0080003738403px; 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: 13.0080003738403px; line-height: 1.538em; font-family: Arial, sans-serif;">Supraventricular rhythm (ventricular rhythms do not travel via the LBB)</span></p><p class="MsoNormal"><span style="text-indent: -0.25in; font-size: 13.0080003738403px; 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: 13.0080003738403px; line-height: 1.538em; font-family: Arial, sans-serif;">The QRS in V1 is negative, and the QRS in Leads I and V6 are positive.</span><span style="font-family: Arial, sans-serif; font-size: 13.0080003738403px; line-height: 1.538em;">&nbsp;</span></p><p class="MsoNormal"><span style="font-family: 'Arial',sans-serif;">The left bundle branch (LBB) can be blocked permanently, temporarily, intermittently, or in the because of a fast rate.&nbsp; When the LBB is blocked, conduction proceeds from the AV junction down the right bundle branch, depolarizing the right ventricle.&nbsp; The impulse travels from the right ventricle across the left ventricle, cell by cell.&nbsp; Conduction is slower this way, and there is asynchrony of the ventricles. This slow conduction and asynchrony of the two ventricles causes widening of the QRS complex.</span></p><p class="MsoNormal"><span style="font-family: 'Arial',sans-serif;">NOTE: &nbsp;It is "normal" for wide-complex rhythms to have ST segment elevation in leads with negative QRS complexes and ST depression in leads with positive QRS complexes. &nbsp;This can make it a bit difficult to determine the ST changes of acute M.I.&nbsp;</span></p><p>&nbsp;</p><p class="MsoNormal"><span style="font-family: 'Arial',sans-serif;">&nbsp;</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/222/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 Left Bundle Branch Block 1/5</option><option value="40">Give Left Bundle Branch Block 2/5</option><option value="60">Give Left Bundle Branch Block 3/5</option><option value="80">Give Left Bundle Branch Block 4/5</option><option value="100" selected="selected">Give Left Bundle Branch Block 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 >2</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-qEJpMnrNjvcq2EZ2Fooc_JAYTw-kvnrSuDWdm-Bnrv0" /> <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-bundle-branch-block-0" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left bundle branch block</a></div><div class="field-item odd"><a href="/ecg/lbbb" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">LBBB</a></div><div class="field-item even"><a href="/ecg/bundle-branch-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">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_4"> <a class="a2a_dd addtoany_share_save" href="https://www.addtoany.com/share#url=https%3A%2F%2Fwww.ecgguru.com%2Fecg%2Fleft-bundle-branch-block&amp;title=Left%20Bundle%20Branch%20Block"><img src="/sites/all/modules/addtoany/images/share_save_256_24.png" width="256" height="24" alt="Share"/></a> </span> </span></li> </ul> Wed, 18 Feb 2015 03:54:54 +0000 Dawn 622 at https://www.ecgguru.com https://www.ecgguru.com/ecg/left-bundle-branch-block#comments Right Bundle Branch Block https://www.ecgguru.com/ecg/right-bundle-branch-block-2 <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/right-bundle-branch-block-2"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/RB108.jpg" width="2054" height="1656" 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>This is an example of right bundle branch block - with a couple of twists. &nbsp;It has the usual ECG characteristics of right bundle branch block: &nbsp;widened QRS (154 ms), supraventricular rhythm (sinus bradycardia), and an rSR' pattern in V1. &nbsp;In addition, wide little S waves are clearly seen in Leads I and V6. &nbsp;This secures the diagnosis of right bundle branch block (RBBB). &nbsp;Each QRS complex in every lead starts off with a very normal appearance, or morphology. &nbsp;Then, as the right ventricle is depolarized late, an additional wave is "added on". &nbsp;This is the R-Prime (R') in V1 and the S wave in Leads I and V6.</p><p><span style="font-size: 12.7272720336914px; line-height: 1.538em;">In most examples of RBBB, you will see the T wave point in the OPPOSITE direction of the terminal wave. &nbsp;So, V1 should have a NEGATIVE T wave. &nbsp;In this example, V2 and V3 should have also had negative T waves. &nbsp;The upright T waves could be considered to have the same significance as inverted T waves in a normal ECG. &nbsp;</span></p><p><span style="font-size: 12.7272720336914px; line-height: 1.538em;">Another interesting aspect to this ECG is the unusual morphology of the terminal S wave in most of the leads. &nbsp;There appears to be a slight notch. &nbsp;Lead V2 even appears to have ST elevation. &nbsp;Perhaps some of our Gurus would comment on this.</span></p><p><span style="font-size: 12.7272720336914px; line-height: 1.538em;">This is a good ECG to use to show how the terminal R' and S waves can sometimes be confused with ST elevation and depression. &nbsp;Lead III has a very flat T wave, and one might make the mistake of calling the R' wave "ST elevation". &nbsp;The R' does not have the sloping shape of a normal ST segment and T wave. &nbsp;Also, all the channels on the ECG are run simultaneously. &nbsp;One needs only to look up at Leads I and II to see where the true T waves are - Lead III's T wave is directly under them.</span></p><p><span style="font-size: 12.7272720336914px; line-height: 1.538em;">This is a very good teaching ECG. &nbsp;We look forward to hearing your comments.</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/222/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 Right Bundle Branch Block 1/5</option><option value="40">Give Right Bundle Branch Block 2/5</option><option value="60">Give Right Bundle Branch Block 3/5</option><option value="80">Give Right Bundle Branch Block 4/5</option><option value="100" selected="selected">Give Right Bundle Branch Block 5/5</option></select> <div class="description"><div class="fivestar-summary fivestar-summary-average-count"><span class="average-rating">Average: <span >4.6</span></span> <span class="total-votes">(<span >5</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--VV3kMleJvGp-iIq7_paOzzRcyoM1eNF0geqGGpyJ8c" /> <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/rbbb" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">RBBB</a></div><div class="field-item even"><a href="/ecg/bundle-branch-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">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_5"> <a class="a2a_dd addtoany_share_save" href="https://www.addtoany.com/share#url=https%3A%2F%2Fwww.ecgguru.com%2Fecg%2Fright-bundle-branch-block-2&amp;title=Right%20Bundle%20Branch%20Block%20"><img src="/sites/all/modules/addtoany/images/share_save_256_24.png" width="256" height="24" alt="Share"/></a> </span> </span></li> </ul> Thu, 25 Dec 2014 03:21:49 +0000 Dawn 611 at https://www.ecgguru.com https://www.ecgguru.com/ecg/right-bundle-branch-block-2#comments Left Bundle Branch Block and Artifact https://www.ecgguru.com/ecg/left-bundle-branch-block-and-artifact <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/left-bundle-branch-block-and-artifact"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/LB116%20w%20artifact_0.jpg" width="1800" height="1351" 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>This ECG offers several teaching opportunities. &nbsp;First, it is an example of left bundle branch block (LBBB). &nbsp;It was obtained from a 53-year-old man who was undergoing a cardiac cath for chest pain. &nbsp;Unfortunately, we do not have access to his past medical history or the results of his cath. &nbsp;The ECG criteria for a diagnosis of LBBB are: &nbsp;1) wide QRS complex; 2) supraventricular rhythm; 3) negative QRS in V1 and positive QRS in V6 and Lead I. &nbsp;This ECG shows normal sinus rhythm at a rate of 88 bpm and a wide QRS at 158 ms (.158 seconds). &nbsp;The QRS in V1 is negatively deflected and in V6 and Lead I it is positive.</p><p>In LBBB, as with any condition that significantly widens the QRS, there will be ST-T changes. &nbsp;The ST segment will deviate in the opposite direction of the QRS. &nbsp;In other words, there will be ST elevation in leads with negative QRS complexes and ST depression in leads with positive QRS complexes. &nbsp;LBBB causes significant difficulty for those trying to diagnose acute ST elevation using ECG alone. &nbsp;Excessive ST elevation in a lead where elevation is expected OR ST elevation in a lead where depression is expected should be considered to be abnormal. &nbsp;At this point, you may find it useful to review <a title="LITFL Sgarbossa Criteria" href="http://lifeinthefastlane.com/ecg-library/basics/sgarbossa/">Sgarbossa's Criteria</a> regarding determining the presence of acute M.I. in the presence of LBBB.</p><p>LBBB can be a serious functonal problem for the patient, as the slow ventricular conduction that causes the wide QRS results in less-than-optimal cardiac output. &nbsp;This associates LBBB with congestive heart failure, both as a cause of CHF and a result of CHF. &nbsp;Many people with LBBB and CHF can be helped by cardiac resynchronization therapy - pacing both ventricles synchronously to narrow the QRS and improve cardiac output. &nbsp;For an excellent article on cardiac pacing in general and CRT (page 2299), go to the 2013 European Society of Cardiology Guidelines as reported by the <a title="EHJ Pacemakers" href="http://eurheartj.oxfordjournals.org/content/ehj/34/29/2281.full.pdf">European Heart Journal, (2013) 34, 2281–2329&nbsp;<span style="font-size: 13.3333339691162px; line-height: 1.538em;">doi:10.1093/eurheartj/eht150</span></a></p><p><span style="font-size: 13.3333339691162px; line-height: 1.538em;">Another reason we have featured this particular ECG, is that there is significant artifact in Leads I, III, and aVL. &nbsp;While this artifact does not prevent us from interpreting this ECG, it is always wise to try to avoid it. &nbsp;In this case, it was easily remedied by replacing the left arm electrode and preparing the skin beneath the electrode by rubbing it with a dry gauze 4x4. &nbsp;You will know your students are learning ECG lead concepts if they can figure out on their own which electrode is the culprit in the artifact. &nbsp;The left arm electrode is the only one shared by these three leads, and Lead II does not use the LA.</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/222/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 Left Bundle Branch Block and Artifact 1/5</option><option value="40">Give Left Bundle Branch Block and Artifact 2/5</option><option value="60">Give Left Bundle Branch Block and Artifact 3/5</option><option value="80">Give Left Bundle Branch Block and Artifact 4/5</option><option value="100" selected="selected">Give Left Bundle Branch Block and Artifact 5/5</option></select> <div class="description"><div class="fivestar-summary fivestar-summary-average-count"><span class="average-rating">Average: <span >4.5</span></span> <span class="total-votes">(<span >2</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-yIREYipEiNGXjHlL18Zy-fq0hcVgFYe1gG7AFcq0XXY" /> <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-bundle-branch-block-0" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left bundle branch block</a></div><div class="field-item odd"><a href="/ecg/lbbb" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">LBBB</a></div><div class="field-item even"><a href="/ecg/bundle-branch-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Bundle branch block</a></div><div class="field-item odd"><a href="/ecg/artifact" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Artifact</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%2Fleft-bundle-branch-block-and-artifact&amp;title=Left%20Bundle%20Branch%20Block%20and%20Artifact"><img src="/sites/all/modules/addtoany/images/share_save_256_24.png" width="256" height="24" alt="Share"/></a> </span> </span></li> </ul> Wed, 26 Nov 2014 02:24:23 +0000 Dawn 608 at https://www.ecgguru.com https://www.ecgguru.com/ecg/left-bundle-branch-block-and-artifact#comments Acute Anterior-lateral M.I. With Right Bundle Branch Block and Left Posterior Fascicular Block https://www.ecgguru.com/ecg/acute-anterior-lateral-mi-right-bundle-branch-block-and-left-posterior-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/acute-anterior-lateral-mi-right-bundle-branch-block-and-left-posterior-fascicular-block"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/AWRB100%20%282%29.jpg" width="1800" height="1282" 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>This ECG was obtained from a patient who suffered an occlusion of the left main coronary artery. &nbsp;ST elevation is seen in Leads V1 through V6, as well as I and aVL. &nbsp;This is an indicator that the circumflex artery is included in this M.I., and the occlusion is above the bifurcation of the LM and the circ. &nbsp;The patient also has a <strong>right bundle branch block</strong>&nbsp;and a <strong>left posterior fascicular block. &nbsp;</strong>This<strong> bi-fascicular block</strong> can be a dangerous complication of acute M.I., as two of the three main bundle branches are no longer functional.</p><p>The ECG shows typical ST depression, probably reciprocal to the elevation, in the inferior leads.</p><p>The right bundle branch block is diagnosed by the following criteria: &nbsp;1) Wide QRS; &nbsp;2) Supraventricular rhythm; and 3) rSR' pattern in V1 with Rs with a wide little s wave in Leads I and V6.</p><p>The left posterior fascicular block is diagnosed by right axis deviation and by ruling out other causes of right axis deviation. &nbsp;In RAD, Lead III will have a taller positive ( R ) wave than Lead II, and a negative Lead I.</p><p>This type of occlusion is often called the "Widow Maker", and requires very rapid intervention to restore blood flow and prevent complicatons. &nbsp;If there is good news, it is that there are no pathological Q waves, which would indicate necrosis, and this patient was taken quickly to a full-service cardiac center with interventional cath labs and open heart surgery available.</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/222/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 Acute Anterior-lateral M.I. With Right Bundle Branch Block and Left Posterior Fascicular Block 1/5</option><option value="40">Give Acute Anterior-lateral M.I. With Right Bundle Branch Block and Left Posterior Fascicular Block 2/5</option><option value="60">Give Acute Anterior-lateral M.I. With Right Bundle Branch Block and Left Posterior Fascicular Block 3/5</option><option value="80">Give Acute Anterior-lateral M.I. With Right Bundle Branch Block and Left Posterior Fascicular Block 4/5</option><option value="100" selected="selected">Give Acute Anterior-lateral M.I. With Right Bundle Branch Block and Left Posterior Fascicular Block 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 >5</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-6y4g7OMOCcB0Th8vzlrcS8ZqrKD6h7FMpsKErmkFpsA" /> <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-wall-mi-5" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Anterior wall M.I.</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/rbbb" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">RBBB</a></div><div class="field-item odd"><a href="/ecg/bundle-branch-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Bundle branch block</a></div><div class="field-item even"><a href="/ecg/left-posterior-fascicular-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left posterior fascicular block</a></div><div class="field-item odd"><a href="/ecg/lpfb" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">LPFB</a></div><div class="field-item even"><a href="/ecg/hemiblock" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Hemiblock</a></div><div class="field-item odd"><a href="/ecg/anterior-lateral-wall-mi" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Anterior-lateral wall M.I.</a></div><div class="field-item even"><a href="/ecg/stemi" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">STEMI</a></div><div class="field-item odd"><a href="/ecg/st-elevation" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">ST elevation</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%2Facute-anterior-lateral-mi-right-bundle-branch-block-and-left-posterior-fascicular-block&amp;title=Acute%20Anterior-lateral%20M.I.%20With%20Right%20Bundle%20Branch%20Block%20and%20Left%20Posterior%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> Thu, 21 Aug 2014 17:45:01 +0000 Dawn 593 at https://www.ecgguru.com https://www.ecgguru.com/ecg/acute-anterior-lateral-mi-right-bundle-branch-block-and-left-posterior-fascicular-block#comments Left Bundle Branch Block https://www.ecgguru.com/ecg/left-bundle-branch-block-2 <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/left-bundle-branch-block-2"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/LB115.jpg" width="2057" height="1566" alt="" /></a></div><div class="field-item odd"><a href="/ecg/left-bundle-branch-block-2"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/LB115%20P%20waves%20marked.jpg" width="200" height="352" alt="" /></a></div><div class="field-item even"><a href="/ecg/left-bundle-branch-block-2"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/LB115%20close%20up%20of%20QRS%20width%20marks.jpg" width="200" height="313" 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>This is a good example of sinus rhythm with left bundle branch block. &nbsp;There is some irregularity due to a PAC at the beginning. &nbsp;The QRS is wide at 144 ms (.14 seconds). &nbsp;There is also first-degree AV block, with a prolonged PR interval of 228 ms. &nbsp;The criteria for diagnosis of left BBB are: &nbsp;wide QRS, supraventricular rhythm, and a negatively-deflected QRS in V1 with a positive QRS in Leads I and V6. &nbsp;</p><p>Left bundle branch block can be associated with many forms of heart disease, including CHF. &nbsp;It can be permanent, transient, intermittent, or rate-related. &nbsp;The wide QRS of LBBB significantly decreases cardiac output, causing poor perfusion symptoms in some people.</p><p>This ECG is a good one for your students who are just transitioning from reading rhythm strips to reading 12-lead ECGs. &nbsp;It shows the value of multi-lead assessment of rhythms. You will notice that P waves are difficult to see in some leads. &nbsp;Armed with the knowledge that the four channels on this ECG are run simultaneously, you can show the students how finding P waves in one lead will allow you to find them in the leads that are above and below that lead.&nbsp;</p><p>Similarly, it can be difficult to see the QRS width in some leads. &nbsp;The leads in the same vertical column can help you see the QRS's true width, even if part of the QRS is "flat" in the isoelectric baseline.</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/222/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 Left Bundle Branch Block 1/5</option><option value="40">Give Left Bundle Branch Block 2/5</option><option value="60">Give Left Bundle Branch Block 3/5</option><option value="80">Give Left Bundle Branch Block 4/5</option><option value="100" selected="selected">Give Left Bundle Branch Block 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--8" name="op" value="Rate" /><input type="hidden" name="form_build_id" value="form-m84hd0bm-5LnDPrrCNqGOpSRKV6LC-nn9AQCrDuk1xk" /> <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-bundle-branch-block-0" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left bundle branch block</a></div><div class="field-item odd"><a href="/ecg/lbbb" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">LBBB</a></div><div class="field-item even"><a href="/ecg/bundle-branch-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Bundle branch block</a></div><div class="field-item odd"><a href="/ecg/multi-lead-assessment" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Multi-lead assessment</a></div><div class="field-item even"><a href="/ecg/left-ventricular-hypertrophy" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left ventricular hypertrophy</a></div><div class="field-item odd"><a href="/ecg/pac" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">PAC</a></div><div class="field-item even"><a href="/ecg/premature-atrial-contraction" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Premature atrial 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_8"> <a class="a2a_dd addtoany_share_save" href="https://www.addtoany.com/share#url=https%3A%2F%2Fwww.ecgguru.com%2Fecg%2Fleft-bundle-branch-block-2&amp;title=Left%20Bundle%20Branch%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, 08 Aug 2014 03:57:36 +0000 Dawn 592 at https://www.ecgguru.com https://www.ecgguru.com/ecg/left-bundle-branch-block-2#comments Left Bundle Branch Block With Left Atrial Enlargement https://www.ecgguru.com/ecg/left-bundle-branch-block-left-atrial-enlargement <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/left-bundle-branch-block-left-atrial-enlargement"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/kio%208-12-13%20from%20Dr.%20Ahmed.jpg" width="1800" height="1363" 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>This ECG, kindly donated by Dr. Ahmed from India, is from a 70-year-old man shows a sinus rhythm at 80 bpm with left bundle branch block (LBBB), left atrial enlargement (LAE), and a premature ventricular contraction (PVC). The ECG criteria for LBBB is: &nbsp;1) Wide QRS &nbsp;- greater than or equal to .12 seconds; &nbsp;2) Supraventricular rhythm; &nbsp;3) QRS that is negative in V1 and positive in Leads I and V6. In leads with a positive QRS, we will see some ST depression, and in leads with a negative QRS, some ST elevation. &nbsp;This is "normal" for the wide QRS rhythm, and does not indicate injury or ischemia, although it does not rule it out, either. &nbsp;LBBB is an indicator of cardiac disease, but not specific to one etiology.</p><p>There is a PVC seen as the 8th beat from the left, and it gives you a chance to show your students a wide-complex beat that is NOT associated with a P wave and is premature, compared to the wide-complex SINUS beats with LBBB. &nbsp;The PVC, being wide-complex, also has similar ST changes: &nbsp;the ST segments and T waves are DISCORDANT with the QRS complexes.</p><p>The P waves show some signs of enlargement of the left atrium. &nbsp;The P waves in Lead II are tall and pointed, and the P waves in V1 are biphasic. &nbsp;Left atrial enlargement in a patient with LBBB would not be surprising, as both are associated with left ventricular dysfunction. &nbsp;Patients with these ECG patterns should be thoroughly evaluated for congestive heart failure. &nbsp;Patients with LBBB, low ejection fractions, and heart failure are treated with cardiac resynchronization therapy, using a pacemaker that paces the atria and each ventricle, synchronizing both the A-V coupling interval and the depolarization of the ventricles for optimum cardiac output.</p><p><a title="LBBB and resynch therapy" href="http://circep.ahajournals.org/content/1/2/127.full">REFERENCE</a>:&nbsp;<span style="font-family: inherit; font-size: inherit; font-style: inherit; font-weight: inherit; line-height: inherit; text-align: inherit; color: #333300; background-color: #dbe5f1;">Circulation: Arrhythmia and Electrophysiology. &nbsp;</span><span class="slug-pub-date" style="color: #333300; font-family: inherit; font-size: inherit; font-style: inherit; font-weight: bold; line-height: inherit; margin-right: -3px; outline-style: none; text-align: inherit;">2008;&nbsp;</span><span class="slug-vol" style="color: #333300; font-family: inherit; font-size: inherit; font-style: inherit; font-weight: inherit; line-height: inherit; margin-right: -3px; outline-style: none; text-align: inherit;">1:&nbsp;</span><span class="slug-pages" style="color: #333300; font-family: inherit; font-size: inherit; font-style: inherit; font-weight: bold; line-height: inherit; outline-style: none; text-align: inherit;">127-139&nbsp;</span><span style="color: #333300; font-family: 'Lucida Sans Unicode', Arial, 'Lucida Grande', Tahoma, Verdana, Helvetica, sans-serif; font-size: 10px; line-height: inherit; background-color: #dbe5f1;">doi: 10.1161/CIRCEP.108.777904</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/222/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 Left Bundle Branch Block With Left Atrial Enlargement 1/5</option><option value="40">Give Left Bundle Branch Block With Left Atrial Enlargement 2/5</option><option value="60">Give Left Bundle Branch Block With Left Atrial Enlargement 3/5</option><option value="80" selected="selected">Give Left Bundle Branch Block With Left Atrial Enlargement 4/5</option><option value="100">Give Left Bundle Branch Block With Left Atrial Enlargement 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--9" name="op" value="Rate" /><input type="hidden" name="form_build_id" value="form-ur0dzsDyP6m_I97AN1eSLwvXYl1G3C0GH4hlswF-hr8" /> <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-bundle-branch-block-0" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left bundle branch block</a></div><div class="field-item odd"><a href="/ecg/lbbb" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">LBBB</a></div><div class="field-item even"><a href="/ecg/bundle-branch-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Bundle branch block</a></div><div class="field-item odd"><a href="/ecg/left-atrial-enlargement" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left atrial enlargement</a></div><div class="field-item even"><a href="/ecg/premature-ventricular-contraction" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Premature ventricular contraction</a></div><div class="field-item odd"><a href="/ecg/fusion-beat" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Fusion beat</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%2Fleft-bundle-branch-block-left-atrial-enlargement&amp;title=Left%20Bundle%20Branch%20Block%20With%20Left%20Atrial%20Enlargement"><img src="/sites/all/modules/addtoany/images/share_save_256_24.png" width="256" height="24" alt="Share"/></a> </span> </span></li> </ul> Mon, 09 Jun 2014 04:29:27 +0000 Dawn 579 at https://www.ecgguru.com https://www.ecgguru.com/ecg/left-bundle-branch-block-left-atrial-enlargement#comments Teaching Series: Atrial Fibrillation With Left Bundle Branch Block https://www.ecgguru.com/ecg/teaching-series-atrial-fibrillation-left-bundle-branch-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-atrial-fibrillation-left-bundle-branch-block"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/LBAF100A.jpg" width="1800" height="751" alt="" /></a></div><div class="field-item odd"><a href="/ecg/teaching-series-atrial-fibrillation-left-bundle-branch-block"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/LBAF100B.jpg" width="1800" height="691" 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>This is a good example of atrial fibrillation with left bundle branch block. &nbsp;You get two ECGs with this one, because the patient presented to EMS with a fast heart rate, and the rate was slowed with the drug diltiazem. &nbsp;We do not have any other patient information, unfortunately.</p><p>In the first strip, we see a wide-complex tachycardia. &nbsp;In an emergency situation, with an unstable patient, this rhythm could safely be treated using an emergency ventricular tachycardia (VT) protocol. &nbsp;In fact, all WCTs should be considered to be VT until proven otherwise. &nbsp;In most emergency settings, the unstable VT patient would be electrically cardioverted, which will often convert atrial fibrillation as well. &nbsp;The stable patient with this rhythm would be treated with an antiarrhythmic drug, such as amiodarone. &nbsp;This may convert or slow down atrial fib. &nbsp;So, in the initial stages of treatment, differentiating between VT and A Fib is not the first priority. &nbsp;Assessing the patient's hemodynamic stability and addressing the rate if necessary are the priorities. &nbsp;</p><p>So, how do we know this is NOT VT? &nbsp;It can be difficult, but in this case, the rhythm, even though fast, is very irregular. &nbsp; VT is not always perfectly regular, but this irregularly-irregular rhythm points to atrial fibrillation. Also, the pattern of the QRS morphology fits with LBBB. &nbsp;The criteria for LBBB are: &nbsp;1) supraventricular rhythm, 2) wide QRS, 3) negative QRS in V1 with positive QRS in Leads I and V6. &nbsp;If we assume the rhythm is atrial fibrillation, we meet the first criteria. &nbsp;The other two are self-evident.</p><p>After the medication is administered, 10 minutes later, we see the rate slow down. &nbsp;There is no change in the irregularly-irregular rhythm, and the LBBB pattern remains. &nbsp;All that has changed is the rate and, hopefully, the patient's symptoms. &nbsp;This confirms that the original rhythm was not VT. &nbsp;</p><p>Remember, atrial fib lowers cardiac output because there is no P wave - no "atrial kick". &nbsp;Also, the fast rate associated with new-onset atrial fib often compromises ventricular filling and cardiac output. &nbsp; LBBB also has a deleterious effect on cardiac output. &nbsp;Wide QRS complexes indicate that the ventricles are not contracting efficiently and synchronously. &nbsp;The left ventricle is depolarizing by way of a slow wave of depolarization, rather than all the cells getting the message to depolarize at the same time. &nbsp;Having these two conditions at the same time can have a very negative effect on cardiac output, leading to CHF. &nbsp;The first step in treatment often involves simply slowing the rate to normal, which allows for better ventricular filling and decreases the workload on the heart. &nbsp;Then, the fibrillation and bundle branch block can be addressed.</p><p>There is some very slight variation in the QRS morphology in both of these ECGs. &nbsp;We will leave it to the more advanced Gurus to comment on this, and any other interesting features we may have missed.</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/222/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 Teaching Series: Atrial Fibrillation With Left Bundle Branch Block 1/5</option><option value="40">Give Teaching Series: Atrial Fibrillation With Left Bundle Branch Block 2/5</option><option value="60" selected="selected">Give Teaching Series: Atrial Fibrillation With Left Bundle Branch Block 3/5</option><option value="80">Give Teaching Series: Atrial Fibrillation With Left Bundle Branch Block 4/5</option><option value="100">Give Teaching Series: Atrial Fibrillation With Left Bundle Branch Block 5/5</option></select> <div class="description"><div class="fivestar-summary fivestar-summary-average-count"><span class="average-rating">Average: <span >2.9</span></span> <span class="total-votes">(<span >8</span> votes)</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-yfAJWCS__7MoxxCN1PPIUIexaVp4QikksjC3STuqNO0" /> <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-bundle-branch-block-0" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left bundle branch block</a></div><div class="field-item odd"><a href="/ecg/lbbb" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">LBBB</a></div><div class="field-item even"><a href="/ecg/bundle-branch-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Bundle branch block</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/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/atrial-fibrillation" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Atrial fibrillation</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%2Fteaching-series-atrial-fibrillation-left-bundle-branch-block&amp;title=Teaching%20Series%3A%20Atrial%20Fibrillation%20With%20Left%20Bundle%20Branch%20Block%20"><img src="/sites/all/modules/addtoany/images/share_save_256_24.png" width="256" height="24" alt="Share"/></a> </span> </span></li> </ul> Fri, 30 May 2014 05:28:19 +0000 Dawn 577 at https://www.ecgguru.com https://www.ecgguru.com/ecg/teaching-series-atrial-fibrillation-left-bundle-branch-block#comments