Concealed P waves https://www.ecgguru.com/taxonomy/term/376/all en Bigeminal Rhythm https://www.ecgguru.com/ecg/bigeminal-rhythm <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/bigeminal-rhythm"><img typeof="foaf:Image" src="https://www.ecgguru.com/sites/default/files/MR116_0.jpg" width="1828" height="1436" 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>To continue a recent theme, we offer this ECG, which appears on quick glance to be an atrial bigeminy. &nbsp;On closer inspection, we do not see ectopic P' waves in the second conducted beats of each pair. &nbsp;In fact, the P waves look the same in both the first and second beats. However, if you look very closely (we enlarged the screen), you may notice that the second T wave of each pair is slightly larger with a slightly different morphology than the first T wave. &nbsp;If this distortion of the second T waves represents a PAC, the PAC is non-conducted and concealed in the T wave. If that concealed P wave is able to penetrate and depolarize the sinus node, we might expect the sinus node to be reset, and the next P wave and QRS combination is right on time.</p><p>So, what looks like an "atrial bigeminy" might actually be an "atrial trigeminy" - albeit with non-conducted PACs.</p><p>Also notable is the subtle ST elevation in V1, V2, and V3, which should be evaluated with clinical data. Unfortunately, we do not have information about the patient. &nbsp;Also, V2 and V3 do not represent normal or expected R wave progression. &nbsp;The chest leads should have rS patterns, and they should progress from small r waves and deep S waves in V1 with gradually taller R waves and shorter S waves across the chest wall. &nbsp;V6 should be, finally, all upright. &nbsp;We suspect lead reversal between V2 and V3, or misplacement of the electrodes in general. &nbsp;Also, the q waves in those leads seem misplaced, without the usual configuration of pathological Q waves in those leads.</p><p><strong>We would love to hear your opinions about this interesting rhythm.</strong></p><p>&nbsp;</p></div></div></div> Sat, 07 Sep 2013 06:09:27 +0000 Dawn 491 at https://www.ecgguru.com