QRS fragmentation https://www.ecgguru.com/taxonomy/term/676/all en Marked Bradycardia With Bifascicular Block https://www.ecgguru.com/ecg/marked-bradycardia-bifascicular-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/marked-bradycardia-bifascicular-block"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/Junctional%20RBBB%20LPH.jpg" width="1800" height="1257" alt="" /></a></div></div></div><div class="field field-name-field-ecg-interpretation field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p class="MsoNormal"><strong><span style="font-size: 12.0pt; line-height: 107%; color: #00b050;">The Patient:</span></strong><span style="font-size: 12.0pt; line-height: 107%; color: #00b050;"><span style="mso-spacerun: yes;">    </span></span><span style="font-size: 12.0pt; line-height: 107%;">This ECG was taken from an elderly woman. Unfortunately, we do not know any details about the case.<span style="mso-spacerun: yes;">  </span>That acknowledged, there are many interesting aspects to this ECG.</span></p><p class="MsoNormal"><strong><span style="font-size: 12.0pt; line-height: 107%; color: #00b050;">The ECG:</span></strong><span style="font-size: 12.0pt; line-height: 107%; color: #00b050;"><span style="mso-spacerun: yes;">  </span></span><span style="font-size: 12.0pt; line-height: 107%;">The first thing we notice is the severe <strong>bradycardia</strong> – almost certain to be symptomatic.<span style="mso-spacerun: yes;">  </span>The rate is 32 bpm and the rhythm is regular.<span style="mso-spacerun: yes;">  </span>There are no P waves.<span style="mso-spacerun: yes;">  </span>This is a <strong>junctional rhythm</strong>, slightly slower than expected from junctional escape.</span></p><p class="MsoNormal"><span style="font-size: 12.0pt; line-height: 107%;">The QRS shows the presence of <strong>right bundle branch block</strong>.<span style="mso-spacerun: yes;">  </span>Each QRS on the ECG starts as a narrow complex, but then adds an “extra” wave onto the end – the delay caused by the right ventricle depolarizing late.<span style="mso-spacerun: yes;">  </span>The terminal delay is very noticeable in V1 as an R’ wave, and in Leads I and V6 as a small, wide s wave.<span style="mso-spacerun: yes;">  </span>There is right axis deviation, so the diagnosis of <strong>bifascicular block</strong> (RBBB and left posterior fascicular block) can be made.</span></p><p class="MsoNormal"><span style="font-size: 12.0pt; line-height: 107%;">V2 through V6 show <strong>fragmentation of the QRS </strong>complexes and a loss of voltage and R wave progression.<span style="mso-spacerun: yes;">  </span>This points to anterior wall M.I. We can’t know the age of the M.I. without clinical correlation, but the ST segments in those leads are very <strong>flat,</strong> with uniformly symmetrical <strong>inverted T waves</strong> all the way to V6.<span style="mso-spacerun: yes;">  </span>All of these signs indicate recent injury.<span style="mso-spacerun: yes;">  </span>An anterior M.I. can cause the bifascicular block we are seeing, since the bundle branches begin in the septum.</span></p></div></div></div> Sun, 10 Jul 2022 20:08:14 +0000 Dawn 817 at https://www.ecgguru.com Right Bundle Branch Block and More https://www.ecgguru.com/ecg/right-bundle-branch-block-and-more <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-and-more"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/SR%20w%20PACs%2011.43.jpg" width="1800" height="663" alt="" /></a></div><div class="field-item odd"><a href="/ecg/right-bundle-branch-block-and-more"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/Leads%2013%2C%2014%2C%2015_0.jpg" width="1800" height="689" alt="" /></a></div></div></div><div class="field field-name-field-ecg-interpretation field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p class="MsoNormal"><strong><span style="font-size: 12.0pt; line-height: 107%; color: #00b050;">The Patient:</span></strong><span style="font-size: 12.0pt; line-height: 107%;"><span style="mso-tab-count: 1;">    </span>These tracings are taken from a 75-year-old man who became weak while playing golf on a very hot day.<span style="mso-spacerun: yes;">  </span>He was pale and diaphoretic.<span style="mso-spacerun: yes;">  </span>He was hypotensive, but we do not know his BP reading. He denies chest pain or discomfort. The patient reported a history of lung cancer and hypertension. We have no other history, and unfortunately, no follow-up information.</span></p><p class="MsoNormal"><strong><span style="font-size: 12.0pt; line-height: 107%; color: #00b050;">ECG Number 1: </span></strong><strong><span style="font-size: 12.0pt; line-height: 107%;"><span style="mso-tab-count: 1;">          </span></span></strong><span style="font-size: 12.0pt; line-height: 107%;">The first ECG shows the standard 12 leads.<span style="mso-spacerun: yes;">  </span>The rhythm is sinus with frequent appearances of PAC couplets.<span style="mso-spacerun: yes;">  </span>The sinus rate varies slightly from about 76 bpm to 68 bpm, tending to slow a bit after the premature atrial contractions.<span style="mso-spacerun: yes;">  </span>There is a right bundle branch block, and the QRS duration is about .12 seconds (120 ms). The PR interval is slightly log at 223 ms.<span style="mso-spacerun: yes;">  </span>We do not know what medications the patient is on, and we do not have an older ECG for comparison.</span></p><p class="MsoNormal"><span style="font-size: 12.0pt; line-height: 107%;">There are some interesting, if subtle, changes worth mentioning.<span style="mso-spacerun: yes;">  </span>The QRS complexes in most leads are fragmented.<span style="mso-spacerun: yes;">  </span>That is, they have notching in the terminal S or R waves that is not due to the bundle branch block. This can be a sign of scarring, and can also be considered an equivalent to a pathological Q wave.<span style="mso-spacerun: yes;">  </span>Speaking of pathological Q waves, they are seen in the inferior leads, II, III, and aVF.<span style="mso-spacerun: yes;">  </span>There are also prominent, though not large Q waves in V4 through V6, leads which normally do not have them. All this points to scarring and possibly long-term coronary artery disease, with possible old M.I.<span style="mso-spacerun: yes;">  </span>In addition, the ST segments are not entirely normal.<span style="mso-spacerun: yes;">  </span>There is ST depression in the inferior and low lateral leads, a little ST elevation in aVL.<span style="mso-spacerun: yes;">  </span>Also, the SHAPES of the ST segments tend to be straight throughout the ECG, instead of the usual curved (concave up) appearance. </span></p></div></div></div> Sat, 22 Aug 2020 21:33:52 +0000 Dawn 788 at https://www.ecgguru.com Inferior-lateral M.I. With QRS Fragmentation https://www.ecgguru.com/ecg/inferior-lateral-mi-qrs-fragmentation <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/inferior-lateral-mi-qrs-fragmentation"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/IW120%20fQRS%20V4R%20ECG6.jpg" width="1800" height="656" alt="" /></a></div></div></div><div class="field field-name-field-ecg-interpretation field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p class="MsoNormal"><strong><span style="font-size: 12.0pt; line-height: 107%;">SUBTLE ST CHANGES   </span></strong><span style="font-size: 12.0pt; line-height: 107%;">This ECG was obtained from an 87-year-old man who was experiencing chest pain.  Due to the subtle ST elevation in Leads II, III, aVF, V<sub>5</sub>, and V<sub>6</sub>, (inferior- lateral walls) the ECG was transmitted to the hospital by the EMS crew, and the cath lab was activated.  The patient denied previous cardiac history.</span><span style="font-size: 8pt; line-height: 107%;"> </span></p><p class="MsoNormal"><span style="font-size: 12.0pt; line-height: 107%;">In addition to the subtle ST elevation, there is ST depression in V<sub>1</sub> through V<sub>4</sub>, which represents a reciprocal view of the injury in the inferior-posterior-lateral wall.  Because the anterior wall is superior in its position in the chest, it is opposite the inferior/posterior wall, and can show ST depression when the inferior-posterior area has ST elevation. This ECG was the 6<sup>th</sup> one done during this EMS call.  Prior to this one, the ST segments were elevated less than 1 mm.  This is a good example of the value of repeat ECGs during an acute event. </span><span style="font-size: 8pt; line-height: 107%;"> </span></p><p class="MsoNormal"><strong><span style="font-size: 12.0pt; line-height: 107%;">RIGHT VENTRICULAR M.I.?     </span></strong><span style="font-size: 12.0pt; line-height: 107%;">This ECG was done with V<sub>4</sub> placed on the right side, to check for right ventricular M.I., which is a protocol for this EMS agency. When the right coronary artery is the culprit artery (about 80% of IWMIs), RVMI is likely.  In RVMI, we would usually see reciprocal ST depression in Leads I and aVL, but the STE is very subtle here, so the depression would likely be also.  When the culprit artery is the left circumflex artery (&lt;20%), lateral lead ST elevation is more likely, as we see here in V<sub>5</sub> and V<sub>6</sub>.</span><span style="font-size: 8pt; line-height: 107%;"> </span></p><p class="MsoNormal"><strong><span style="font-size: 12.0pt; line-height: 107%;">WHAT ABOUT RHYTHM?</span></strong><span style="font-size: 12.0pt; line-height: 107%;">     The rhythm is sinus with PACs.  PACs are considered to be benign in most situations, but in a patient with acute M.I., any dysrhythmia can be concerning. The QT interval, measured as QTc (corrected to a heart rate of 60 bpm), is slightly prolonged at .458 seconds (458 ms).  Over .440 seconds is considered prolonged in men, and over .500 sec. places the patient at increased risk of developing torsades de pointes.  CAD and myocardial ischemia can lead to this modest increase in QTc.</span></p></div></div></div> Sun, 14 Aug 2016 05:33:04 +0000 Dawn 707 at https://www.ecgguru.com