ECG Guru - Instructor Resources - Wide QRS complex https://www.ecgguru.com/ecg/wide-qrs-complex en Ask The Expert https://www.ecgguru.com/expert-review/ask-expert-15 <div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even" property="content:encoded"><p class="MsoNormal"><strong><span style="font-size: 20.0pt; line-height: 107%; color: #7030a0;">Dr. Jerry W. Jones, MD, FACEP, FAAEM has graciously shared with us his four-part article on the topic of “Delays &amp; Blocks Involving the Bundle Branches”.</span></strong></p><p class="MsoNormal"><span style="font-size: 16.0pt; line-height: 107%;">Dr. Jones is a talented instructor who makes difficult topics easy.<span style="mso-spacerun: yes;">&nbsp; </span>Please feel free to post your comments and questions for Dr. Jones and our other ECG Gurus.<span style="mso-spacerun: yes;">&nbsp; </span></span></p><p class="MsoNormal"><span style="font-size: 16.0pt; line-height: 107%;">Click <a title="IVCD" href="https://www.ecgguru.com/sites/default/files/resource-docs/Part%201_0.pdf">THIS LINK</a> for a downloadable pdf of Part 1: Non-Specific Intraventricular Conduction Delays.&nbsp; </span></p><p class="MsoNormal"><span style="font-size: 16.0pt; line-height: 107%;">Click <a title="Left Bundle Branch Block" href="https://www.ecgguru.com/sites/default/files/resource-docs/Part%202.pdf">THIS LINK</a> for a downloadable pdf of Part 2: Left Bundle Branch Block.</span></p><p class="MsoNormal"><span style="font-size: 16.0pt; line-height: 107%;">Click <a title="Right Bundle Branch Block" href="https://www.ecgguru.com/sites/default/files/resource-docs/Part%203.pdf">THIS LINK</a> for a downloadable pdf of Part 3: Right Bundle Branch Block.</span></p><p class="MsoNormal"><span style="font-size: 16.0pt; line-height: 107%;">Click <a title="The Fascicles of the Left Bundle Branch" href="https://www.ecgguru.com/sites/default/files/resource-docs/Part%204.docx.pdf">THIS LINK</a> for a downloadable pdf of Part 4: The Fascicles of the Left Bundle Branch&nbsp;</span></p></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/non-specific-intraventricular-conduction-delay" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Non-specific intraventricular conduction delay</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/wide-qrs-complex" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Wide QRS complex</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%2Fexpert-review%2Fask-expert-15&amp;title=Ask%20The%20Expert"><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> Fri, 01 Oct 2021 20:38:34 +0000 Dawn 802 at https://www.ecgguru.com https://www.ecgguru.com/expert-review/ask-expert-15#comments Tachycardia In An Unresponsive Patient https://www.ecgguru.com/ecg/tachycardia-unresponsive-patient <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/tachycardia-unresponsive-patient"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/Tachycardia%20and%20Hyperkalemia.jpg" width="1800" height="713" 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;">&nbsp;</strong><strong style="font-size: 13.008px;"><span style="font-size: 10.0pt; line-height: 107%; color: #00b050;">The Patient</span></strong><span style="font-size: 10pt; line-height: 107%; color: #00b050;">&nbsp;&nbsp;&nbsp;&nbsp; </span><span style="font-size: 10pt; line-height: 107%;">This ECG was obtained from a 28-year-old woman who was found in her home, unresponsive.&nbsp; She was hypotensive at 99/35.&nbsp; No one was available to provide information about past medical history or the onset of this event.</span></p><p class="MsoNormal"><span style="font-size: 10.0pt; line-height: 107%;">Before you read my comments, pause to look at the ECG and see what YOU think.<span style="mso-spacerun: yes;">&nbsp; </span>We would welcome comments below from all our members!</span></p><p class="MsoNormal"><strong style="mso-bidi-font-weight: normal;"><span style="font-size: 10.0pt; line-height: 107%; color: #00b050;">The ECG</span></strong><span style="font-size: 10.0pt; line-height: 107%; color: #00b050;"><span style="mso-spacerun: yes;">&nbsp;&nbsp;&nbsp;&nbsp; </span></span><span style="font-size: 10.0pt; line-height: 107%;">This ECG is quite challenging, as it illustrates the helpfulness of ECG changes in patient diagnosis, and also points out how important clinical correlation is when the ECG suggests multiple different problems. Forgive me in advance, but there is a lot to say about this ECG.</span></p><p class="MsoNormal"><span style="font-size: 10.0pt; line-height: 107%;">The <strong style="mso-bidi-font-weight: normal;">heart rate</strong> is 148 bpm, and the <strong style="mso-bidi-font-weight: normal;">rhythm is regular</strong>, although not perfectly. <strong style="mso-bidi-font-weight: normal;">P waves</strong> are not seen, even though the ECG machine gives a P wave axis and PR interval measurement. The rate is fast enough to bury the P waves in the preceding T waves, especially if there is first-degree AV block. <strong style="mso-bidi-font-weight: normal;"><em style="mso-bidi-font-style: normal;"><span style="color: #7030a0;">Differential dx</span></em></strong><em style="mso-bidi-font-style: normal;"><span style="color: #7030a0;">:</span></em><span style="color: #7030a0;"> sinus tachycardia, PSVT, atrial flutter. </span>The very slight irregularity points more towards sinus tachycardia.<span style="mso-spacerun: yes;">&nbsp; </span>The rate of nearly 150 suggests atrial flutter with 2:1 conduction, but the only lead that looks remotely like it has flutter waves is V2. The lack of an onset or offset of the rhythm makes it difficult to diagnose PSVT with any certainty. </span></p><p class="MsoNormal"><span style="font-size: 10.0pt; line-height: 107%;">The ECG machine measures the QRS complex at .102 seconds (102 ms). I don’t believe this is correct, as the QRS has an additional wave due to <strong style="mso-bidi-font-weight: normal;"><a href="https://www.ecgguru.com/ecg/instructors-collection-ecg-week-september-23-2015-right-bundle-branch-block-0">right bundle branch block pattern</a></strong>, and the machine did not count this terminal wave.<span style="mso-spacerun: yes;">&nbsp; </span>I measure the actual <strong style="mso-bidi-font-weight: normal;">QRS duration</strong> at closer to .12 seconds (120 ms).<span style="mso-spacerun: yes;">&nbsp; </span>The J point, or end point of the QRS complex, is difficult to see in most of the leads because of slurring from the QRS to the ST segment.<span style="mso-spacerun: yes;">&nbsp; </span></span></p><p class="MsoNormal"><strong style="mso-bidi-font-weight: normal;"><em style="mso-bidi-font-style: normal;"><span style="font-size: 10.0pt; line-height: 107%; color: #7030a0;">Differential dx:</span></em></strong><span style="font-size: 10.0pt; line-height: 107%;"><span style="mso-spacerun: yes;">&nbsp;&nbsp; </span>There are some signs of <strong style="mso-bidi-font-weight: normal;"><a href="https://litfl.com/ecg-changes-in-pulmonary-embolism/">right ventricular failure</a></strong> on this ECG, but ECG is not 100% accurate for determining right heart strain. The ECG evidence must be confirmed by clinical correlation. <span style="mso-spacerun: yes;">&nbsp;</span>In a young person with sudden onset of right heart failure signs, one must consider <strong style="mso-bidi-font-weight: normal;">pulmonary embolus</strong>.<span style="mso-spacerun: yes;">&nbsp; </span>Some, but not all, of the ECG signs that can be associated with pulmonary embolism are:</span></p><p class="MsoListParagraphCxSpFirst" style="margin-left: 30.75pt; mso-add-space: auto; text-indent: -.25in; mso-list: l1 level1 lfo1;"><!--[if !supportLists]--><span style="font-size: 10.0pt; line-height: 107%; 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;&nbsp; </span></span></span><!--[endif]--><span style="font-size: 10.0pt; line-height: 107%;">Sinus tachycardia (44%)</span></p><p class="MsoListParagraphCxSpMiddle" style="margin-left: 30.75pt; mso-add-space: auto; text-indent: -.25in; mso-list: l1 level1 lfo1;"><!--[if !supportLists]--><span style="font-size: 10.0pt; line-height: 107%; 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;&nbsp; </span></span></span><!--[endif]--><span style="font-size: 10.0pt; line-height: 107%;">Right bundle branch block or incomplete RBBB (18%)</span></p><p class="MsoListParagraphCxSpMiddle" style="margin-left: 30.75pt; mso-add-space: auto; text-indent: -.25in; mso-list: l1 level1 lfo1;"><!--[if !supportLists]--><span style="font-size: 10.0pt; line-height: 107%; 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;&nbsp; </span></span></span><!--[endif]--><span style="font-size: 10.0pt; line-height: 107%;">Right ventricular strain: T wave inversion in right precordial leads and inferior leads (only present here in V1 and Lead III, which is often normal).</span></p><p class="MsoListParagraphCxSpMiddle" style="margin-left: 30.75pt; mso-add-space: auto; text-indent: -.25in; mso-list: l1 level1 lfo1;"><!--[if !supportLists]--><span style="font-size: 10.0pt; line-height: 107%; 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;&nbsp; </span></span></span><!--[endif]--><span style="font-size: 10.0pt; line-height: 107%;">Right axis deviation (16%).<span style="mso-spacerun: yes;">&nbsp; </span>Present here, but not severe at around 100 degrees.</span></p><p class="MsoListParagraphCxSpMiddle" style="margin-left: 30.75pt; mso-add-space: auto; text-indent: -.25in; mso-list: l1 level1 lfo1;"><!--[if !supportLists]--><span style="font-size: 10.0pt; line-height: 107%; 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;&nbsp; </span></span></span><!--[endif]--><span style="font-size: 10.0pt; line-height: 107%;">S1 – Q3 – T3 the “classic” but not often present, sign of pulmonary embolism.<span style="mso-spacerun: yes;">&nbsp; </span>The<span style="mso-spacerun: yes;">&nbsp; </span>S wave in I may simply be the RBBB and the Q wave with T wave inversion may be a normal variant.</span></p><p class="MsoListParagraphCxSpMiddle" style="margin-left: 30.75pt; mso-add-space: auto; text-indent: -.25in; mso-list: l1 level1 lfo1;"><!--[if !supportLists]--><span style="font-size: 10.0pt; line-height: 107%; 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;&nbsp; </span></span></span><!--[endif]--><span style="font-size: 10.0pt; line-height: 107%;">Non-specific ST segment and T wave changes (50%)</span></p><p class="MsoListParagraphCxSpLast" style="margin-left: 30.75pt; mso-add-space: auto; text-indent: -.25in; mso-list: l1 level1 lfo1;"><!--[if !supportLists]--><span style="font-size: 10.0pt; line-height: 107%; 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;&nbsp; </span></span></span><!--[endif]--><span style="font-size: 10.0pt; line-height: 107%;">P pulmonale (we cannot see P waves)</span></p><p class="MsoNormal"><span style="font-size: 10.0pt; line-height: 107%;">There are also ST and T wave changes that resemble <strong style="mso-bidi-font-weight: normal;"><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6282764/">Brugada Syndrome</a>, </strong>a genetic disorder of the sodium channel that can cause sudden death.<span style="mso-spacerun: yes;">&nbsp; </span>Illness can unmask the ECG changes that point to Brugada syndrome, but also there are conditions that cause similar ECG changes without the patient actually having a channelopathy. The shape of the ST and inverted T wave in V1 here are “Brugada like”. In Brugada Syndrome, those changes are usually seen in V1 and V2.<span style="mso-spacerun: yes;">&nbsp; </span></span></p><p class="MsoNormal"><span style="font-size: 10.0pt; line-height: 107%;">The loss of P waves and the tall, peaked T waves with narrow bases are indicative of <strong style="mso-bidi-font-weight: normal;"><a href="https://rebelem.com/ecg-changes-hyperkalemia/">hyperkalemia</a></strong>. It is difficult to determine just from the ECG how far along the patient is in serum potassium levels, but widening of the QRS with loss of voltage is a dire sign.<span style="mso-spacerun: yes;">&nbsp; </span>Because hyperkalemia can progress swiftly to a “sine wave” pattern, it is crucial to make the diagnosis and begin treatment as soon as possible.<span style="mso-spacerun: yes;">&nbsp; </span>Usually, the serum K is high because the K has moved out of the intracellular space and entered the serum. Rather than remove K from the body, it is necessary to “push” it back into the cells, where it rightly belongs.<span style="mso-spacerun: yes;">&nbsp; </span></span></p><p class="MsoNormal" style="margin-bottom: .0001pt;"><span style="font-size: 10.0pt; line-height: 107%;">And, to make matters even more confusing, this ECG show signs of drug toxicity, specifically <strong style="mso-bidi-font-weight: normal;"><a href="https://litfl.com/tricyclic-overdose-sodium-channel-blocker-toxicity/">sodium channel blocker overdose</a>.<span style="mso-spacerun: yes;">&nbsp; </span></strong>Tricyclic antidepressants and some antiarrhythmics fall into this broad category. <span style="mso-spacerun: yes;">&nbsp;</span>Remember, this patient was found unresponsive, and we have no remote OR recent medical history.<span style="mso-spacerun: yes;">&nbsp; </span>Everything is on the table.<span style="mso-spacerun: yes;">&nbsp;&nbsp; </span><span style="mso-spacerun: yes;">&nbsp;</span>ECG signs of sodium channel blocker OD include:</span></p><p class="MsoListParagraphCxSpFirst" style="margin-left: 30.75pt; mso-add-space: auto; text-indent: -.25in; mso-list: l0 level1 lfo2;"><!--[if !supportLists]--><span style="font-size: 10.0pt; line-height: 107%; 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;&nbsp; </span></span></span><!--[endif]--><span style="font-size: 10.0pt; line-height: 107%;">Sinus tachycardia</span></p><p class="MsoListParagraphCxSpMiddle" style="margin-left: 30.75pt; mso-add-space: auto; text-indent: -.25in; mso-list: l0 level1 lfo2;"><!--[if !supportLists]--><span style="font-size: 10.0pt; line-height: 107%; 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;&nbsp; </span></span></span><!--[endif]--><span style="font-size: 10.0pt; line-height: 107%;">Wide QRS complex</span></p><p class="MsoListParagraphCxSpMiddle" style="margin-left: 30.75pt; mso-add-space: auto; text-indent: -.25in; mso-list: l0 level1 lfo2;"><!--[if !supportLists]--><span style="font-size: 10.0pt; line-height: 107%; 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;&nbsp; </span></span></span><!--[endif]--><span style="font-size: 10.0pt; line-height: 107%;">Prolongation of the PR interval or QT interval</span></p><p class="MsoListParagraphCxSpMiddle" style="margin-left: 30.75pt; mso-add-space: auto; text-indent: -.25in; mso-list: l0 level1 lfo2;"><!--[if !supportLists]--><span style="font-size: 10.0pt; line-height: 107%; 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;&nbsp; </span></span></span><!--[endif]--><span style="font-size: 10.0pt; line-height: 107%;">Right bundle branch block</span></p><p class="MsoListParagraphCxSpLast" style="margin-left: 30.75pt; mso-add-space: auto; text-indent: -.25in; mso-list: l0 level1 lfo2;"><!--[if !supportLists]--><span style="font-size: 10.0pt; line-height: 107%; 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;&nbsp; </span></span></span><!--[endif]--><span style="font-size: 10.0pt; line-height: 107%;">Brugada pattern</span></p><p class="MsoNormal" style="margin-bottom: .0001pt; line-height: normal;"><strong style="mso-bidi-font-weight: normal;"><span style="font-size: 10.0pt; color: #00b050;">Hospital Follow Up<span style="mso-spacerun: yes;">&nbsp;&nbsp;&nbsp;&nbsp; </span></span></strong><span style="font-size: 10.0pt;">At this time, we have only a preliminary follow up report.<span style="mso-spacerun: yes;">&nbsp; </span>Notably, this young woman was found to be in <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5298445/">diabetic ketoacidosis</a>, with a blood glucose level of 1,332 mg/dL! As a result, she was also hyperkalemic, with a serum potassium of 8.2.<span style="mso-spacerun: yes;">&nbsp; </span>The severe dehydration and acidosis of DKA cause sinus tachycardia.</span></p><p class="MsoNormal"><strong style="mso-bidi-font-weight: normal;"><em style="mso-bidi-font-style: normal;"><span style="font-size: 10.0pt; line-height: 107%; color: #595959; mso-themecolor: text1; mso-themetint: 166; mso-style-textfill-fill-color: #595959; mso-style-textfill-fill-themecolor: text1; mso-style-textfill-fill-alpha: 100.0%; mso-style-textfill-fill-colortransforms: 'lumm=65000 lumo=35000';">Thanks to Sebastian Garay for donating this interesting ECG.</span></em></strong></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/759/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 Tachycardia In An Unresponsive Patient 1/5</option><option value="40">Give Tachycardia In An Unresponsive Patient 2/5</option><option value="60">Give Tachycardia In An Unresponsive Patient 3/5</option><option value="80" selected="selected">Give Tachycardia In An Unresponsive Patient 4/5</option><option value="100">Give Tachycardia In An Unresponsive Patient 5/5</option></select> <div class="description"><div class="fivestar-summary fivestar-summary-average-count"><span class="average-rating">Average: <span >3.6</span></span> <span class="total-votes">(<span >16</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-NxFq6vUs1RJZWqKnHzjZIdAvzbvpECwqDCci_Y_XETs" /> <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/sinus-tachycardia" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Sinus tachycardia</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/bifascicular-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Bifascicular block</a></div><div class="field-item even"><a href="/ecg/left-posterior-hemiblock" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Left posterior hemiblock</a></div><div class="field-item odd"><a href="/ecg/right-axis-deviation" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Right axis deviation</a></div><div class="field-item even"><a href="/ecg/sa-exit-block" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">SA exit block</a></div><div class="field-item odd"><a href="/ecg/wide-qrs-complex" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Wide QRS complex</a></div><div class="field-item even"><a href="/ecg/diabetic-ketoacidosis" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Diabetic ketoacidosis</a></div><div class="field-item odd"><a href="/ecg/hyperkalemia" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Hyperkalemia</a></div><div class="field-item even"><a href="/ecg/brugada-sign" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Brugada sign</a></div><div class="field-item odd"><a href="/ecg/tricyclic-antidepressant-overdose" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Tricyclic antidepressant overdose</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%2Ftachycardia-unresponsive-patient&amp;title=Tachycardia%20In%20An%20Unresponsive%20Patient"><img src="/sites/all/modules/addtoany/images/share_save_256_24.png" width="256" height="24" alt="Share"/></a> </span> </span></li> </ul> Wed, 21 Aug 2019 02:48:51 +0000 Dawn 775 at https://www.ecgguru.com https://www.ecgguru.com/ecg/tachycardia-unresponsive-patient#comments Wide QRS Complex With First-degree AV Block https://www.ecgguru.com/ecg/wide-qrs-complex-first-degree-av-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/wide-qrs-complex-first-degree-av-block"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/IVCD_0.jpg" width="1800" height="983" 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;">The Patient:<span style="mso-spacerun: yes;">&nbsp; </span></span></strong>This ECG was taken from a 73-year-old man with a history of heart failure with preserved ejection fraction, severe left ventricular hypertrophy, Type II diabetes, and stage 4 chronic kidney disease.<span style="mso-spacerun: yes;">&nbsp; </span>He also suffered deep vein thrombosis and is on anticoagulation.<span style="mso-spacerun: yes;">&nbsp; </span>He has a recent diagnosis of IgA myeloma.<span style="mso-spacerun: yes;">&nbsp; </span>He presented with a complaint of nausea and vomiting and was found to have a worsening of acute kidney infection.<span style="mso-spacerun: yes;">&nbsp; </span>There was suspicion of renal and cardiac amyloidosis, but the patient refused biopsy to confirm this.<span style="mso-spacerun: yes;">&nbsp; </span>He was started on chemotherapy for multiple myeloma and will be followed as an outpatient.</p><p class="MsoNormal"><strong style="mso-bidi-font-weight: normal;"><span style="color: #00b050;">The ECG:</span></strong><span style="color: #00b050;"><span style="mso-spacerun: yes;">&nbsp; </span></span>The rhythm is <strong style="mso-bidi-font-weight: normal;">sinus</strong> at around 60 bpm, although the rate varies a little at the beginning of the strip.<span style="mso-spacerun: yes;">&nbsp; </span>The QRS complex is wide at .12 seconds, or 120 ms., representing <strong style="mso-bidi-font-weight: normal;">interventricular conduction</strong> <strong style="mso-bidi-font-weight: normal;">delay (IVCD)</strong>.<span style="mso-spacerun: yes;">&nbsp; </span>The PR interval is .32 seconds, or 320 ms. This constitutes <strong style="mso-bidi-font-weight: normal;">first-degree AV block.<span style="mso-spacerun: yes;">&nbsp; </span></strong>There is left axis deviation in the frontal plane and poor R wave progression in the horizontal plane.</p><p class="MsoNormal"><strong style="mso-bidi-font-weight: normal;"><span style="color: #00b050;">Wide QRS:</span></strong><span style="color: #00b050;"><span style="mso-spacerun: yes;">&nbsp;&nbsp; </span></span>When confronted with wide QRS, there are many diagnostic possibilities.<span style="mso-spacerun: yes;">&nbsp; </span>We can rule out a ventricular origin for the beats, as there are P waves consistently before each QRS. There is no history given of the presence of electronic pacemaker, and no obvious spikes.<span style="mso-spacerun: yes;">&nbsp; </span>One of the most common forms of IVCD is <strong style="mso-bidi-font-weight: normal;">left bundle branch block</strong>. In this ECG, V1 has the appearance of LBBB with it’s monophasic, wide QS pattern.<span style="mso-spacerun: yes;">&nbsp; </span>However Leads I and V6 do not have the typical LBBB pattern, which would be broad, positive QRS complexes. By ruling out obvious causes of the conduction delay, we are forced to simply call it “<strong style="mso-bidi-font-weight: normal;">interventricular conduction delay (or defect)”.</strong></p><p class="MsoNormal">Conduction delays below the level of the bundle of His can occur any place along the interventricular conduction system, and can even be a feature of the thickened or dilated left ventricle. One way to pinpoint the area of conduction delay is with electrophysiology studies.</p><p class="MsoNormal">In the past, patients who showed signs of LBBB (a bifascicular block) and first-degree AVB were said to have “trifascicular block”. This term is now outdated, and it is felt that it is preferable to just describe the conduction delays seen. The majority of first-degree AV blocks occur at the AV node level, but in the presence of LBBB, first-degree AVB can represent a conduction defect in the right bundle branch. <span style="mso-spacerun: yes;">&nbsp;</span>Of course, EP studies can make the naming of blocks and conduction delays much more accurate. <a href="https://www.ahajournals.org/doi/pdf/10.1161/01.CIR.43.4.491">A 1971 study</a> explored the occurance and location of first-degree AVB in the setting of interventricular conduction delays.</p><p class="MsoNormal"><strong style="mso-bidi-font-weight: normal;"><span style="color: #00b050;">Left Ventricular Enlargement:</span></strong><span style="color: #00b050;"><span style="mso-spacerun: yes;">&nbsp; </span><span style="mso-spacerun: yes;">&nbsp;</span></span>(a term including hypertrophy and dilatation).<span style="mso-spacerun: yes;">&nbsp; </span>The QRS complexes on this ECG do not meet the <a href="https://litfl.com/left-ventricular-hypertrophy-lvh-ecg-library/">Sokolov-Lyon</a> criteria for LVH, but LVH is not diagnosed by ECG findings, which tend to be less than reliable. This patient’s known history of LVH is presumably confirmed by xray and echocardiogram. The slight <strong style="mso-bidi-font-weight: normal;">ST elevations</strong> in V2, V3, and V4 are typical of wide-complex rhythms, in that they are “discordant” to the QRS direction, and proportional to the size of the QRS.<span style="mso-spacerun: yes;">&nbsp; </span>That is, the ST and T waves will point in a direction opposite that of the QRS, and there will be most notable ST elevation or depression in the leads with the tallest or deepest QRS complexes. For more on evaluation of ST elevation or depression in the presence of broad-complexes, see Dr. Smith’s work on the <a href="http://hqmeded-ecg.blogspot.com/2015/11/validation-of-smith-modified-sgarbossa.html">modified Sgarbossa criteria</a>.</p><p class="MsoNormal">It is safe to say that this unfortunate patient has plenty of clinical history to have the ECG changes seen here, and that there are no acute ECG findings.<span style="mso-spacerun: yes;">&nbsp; </span></p><p class="MsoNormal"><strong style="mso-bidi-font-weight: normal;">We would like to thank Dr. Ahmad Nawid Latifi for sharing this most interesting case with us.<span style="mso-spacerun: yes;">&nbsp; </span>You will find another, similar case from Dr. Latifi <a href="https://ecgguru.com/ecg/instructors-collection-ecg-bifascicular-block-first-degree-avb">here</a>.<span style="mso-spacerun: yes;">&nbsp; </span>Some of the discussion is relevant to both ECGs.</strong></p><p class="MsoNormal"><strong style="mso-bidi-font-weight: normal;"><br /></strong></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/759/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 QRS Complex With First-degree AV Block 1/5</option><option value="40">Give Wide QRS Complex With First-degree AV Block 2/5</option><option value="60" selected="selected">Give Wide QRS Complex With First-degree AV Block 3/5</option><option value="80">Give Wide QRS Complex With First-degree AV Block 4/5</option><option value="100">Give Wide QRS Complex With First-degree AV Block 5/5</option></select> <div class="description"><div class="fivestar-summary fivestar-summary-average-count"><span class="average-rating">Average: <span >3</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--2" name="op" value="Rate" /><input type="hidden" name="form_build_id" value="form-TTkcVO6J0TGAWtPQATP6oQ6pxebQygMwIIPXa4nPiwU" /> <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/interventricular-conduction-delay" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Interventricular conduction delay</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/wide-qrs-complex" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Wide QRS complex</a></div><div class="field-item odd"><a href="/ecg/amyloidosis" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Amyloidosis</a></div><div class="field-item even"><a href="/ecg/smith-modified-sgarbossa-criteria" typeof="skos:Concept" property="rdfs:label skos:prefLabel" datatype="">Smith Modified Sgarbossa Criteria</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 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></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%2Fwide-qrs-complex-first-degree-av-block&amp;title=Wide%20QRS%20Complex%20With%20First-degree%20AV%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, 07 Jun 2019 20:48:29 +0000 Dawn 769 at https://www.ecgguru.com https://www.ecgguru.com/ecg/wide-qrs-complex-first-degree-av-block#comments