tag:blogger.com,1999:blog-3364570834099131201.post8433822619073236681..comments2024-03-23T08:57:50.965-04:00Comments on ECG Interpretation: ECG Blog #211 — Why Aberrant Conduction?ECG Interpretationhttp://www.blogger.com/profile/02309020028961384995noreply@blogger.comBlogger4125tag:blogger.com,1999:blog-3364570834099131201.post-57421548001417423482021-10-30T19:52:18.701-04:002021-10-30T19:52:18.701-04:00THANKS for your question. The reason we know with ...THANKS for your question. The reason we know with 99.99% certainty that beat #12 is an aberrantly conducted supraventricular beat (and NOT a PVC) — is because it’s morphology is absolutely classic for RBBB-aberrancy conduction (ie, an rSR’, with S that descends below the baseline — and with slender, taller Right “Rabbit Ear”). Everything else on this tracing is a PAC — so it would not be expected to suddenly see a PVC … We get into some semantics as to whether we call early beat #12 a “PAC” — or whether this is a reentry beat, that IF this sequence would have continued, might have evolved into a reentry SVT rhythm …<br /><br />Please check out Audio Pearl #67 in ECG Blog #253 (http://tinyurl.com/KG-Blog-253) — which is devoted to the concept, “Birds of a Feather” — which is why we KNOW beat #12 with identical QRS morphology as definitively diagnosed supraventricular beats #3 and 11 — is also a supraventricular beat with RBBB aberration (and not a PVC) — :)<br />ECG Interpretationhttps://www.blogger.com/profile/02309020028961384995noreply@blogger.comtag:blogger.com,1999:blog-3364570834099131201.post-6157690438653335422021-10-29T23:57:34.554-04:002021-10-29T23:57:34.554-04:00Sir, We know that beats 3,7,11 of panel A are PAC ...Sir, We know that beats 3,7,11 of panel A are PAC with aberrancy because we can clearly see an early P wave occurring - buried within the preceding T wave.<br />But how can we tell if Beat 12 is also a PAC, since we cant see any P wave preceding it ?<br />Can it be PJC with aberrancy? or a PVC ?Kenhttps://www.blogger.com/profile/17266588380020804028noreply@blogger.comtag:blogger.com,1999:blog-3364570834099131201.post-75216150812725083552021-04-08T19:48:07.334-04:002021-04-08T19:48:07.334-04:00There are many possible causes of PACs — which inc...There are many possible causes of PACs — which include stimulants (ie, caffeine, alcohol, cocaine or other stimulant medications) — dehydration — hypoxemia — heart failure — fluid and electrolyte or acid-base problems — “sick patient” — psychological stress — inadequate sleep — etc., etc.).<br /><br />And MUITO OBRIGADO O Poder — for your 2nd question. Somehow, I forgot to make any mention of the baseline QRS widening in Rhythm B. The reason for this is preexisting bundle branch block. We KNOW that the rhythm is sinus — because there is an upright P wave with constant (albeit prolonged) PR interval in this lead II rhythm strip. THANKS to YOU — I have just now ADDED a bullet to the text, so as to emphasize the reason for the baseline QRS widening in Rhythm B! — :)ECG Interpretationhttps://www.blogger.com/profile/02309020028961384995noreply@blogger.comtag:blogger.com,1999:blog-3364570834099131201.post-10286234047805022892021-04-07T15:52:30.351-04:002021-04-07T15:52:30.351-04:00Nice post. I have some questions. Why do PAC occur...Nice post. I have some questions. Why do PAC occur? What is your etiology? Why QRS is wide in Rhythm B? Thanks a lot, my professor. O Poder da Eletrocardiografiahttps://www.blogger.com/profile/11143192155299060176noreply@blogger.com