tag:blogger.com,1999:blog-549949223388475481.post1112026969484216842..comments2024-03-28T14:02:08.119-05:00Comments on Dr. Smith's ECG Blog: Chest pain and a non-diagnostic ECG. No worries, right?Unknownnoreply@blogger.comBlogger5125tag:blogger.com,1999:blog-549949223388475481.post-39085071914965598522018-02-11T12:17:22.181-06:002018-02-11T12:17:22.181-06:00Thanks, tom!!Thanks, tom!!Steve Smithhttps://www.blogger.com/profile/08027289511840815536noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-79903209753793932232018-02-09T05:26:42.128-06:002018-02-09T05:26:42.128-06:00thank you, gentlemen. interesting conversations on...thank you, gentlemen. interesting conversations on what appear on quick glance to be very benign. (and resulting in v-fib arrest)<br />thank youtom fieronoreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-63939249286700163352018-02-06T05:44:40.114-06:002018-02-06T05:44:40.114-06:00Our THANKS to Dr. Stephen Smith for showing us thi...Our THANKS to Dr. Stephen Smith for showing us this case — which is humbling and highly educational. Superb pearl by Vince DeGiulio. There is no denying the subtle J-point ST depression in lead V3 on the original tracing (plus as mentioned by Dr. Smith — suggestion of a taller-than-expected T wave in lead II, plus an unexpectedly small negative T wave in lead V2). That said — despite the “high pre-test probability” of an acute event (because this patient had chest pain, and because Dr. Smith posted this case on his ECG Blog) — I also thought the changes on these 3 tracings were non diagnostic … That said, it is good to appreciate that there IS slight serial change (ie, when one compares ECG #3 to ECG #1 — the T wave in V2 is no longer negative, and there is no longer any J-point ST depression in lead V3 DESPITE absolutely no change in lead placement in view of identical QRS morphology on both tracings). This brings home 4 points: i) As per Dr. Smith — Even complete acute coronary occlusion may not always produce diagnostic ECG signs; ii) As per Vince — subtle ST depression in V3, but no ST depression in V6 in a patient with new-onset worrisome chest pain suggests that there may be LCx occlusion until you prove otherwise; iii) I’ll add to Vince’s pearl, that in my experience — subtle change in lead II not explained by clear ST elevation in leads III and aVF in a patient with new-onset worrisome chest pain also suggests the LCx is more likely to be the “culprit artery” (and the T wave in lead II here IS taller-than-we-should-expect on all 3 tracings given very modest QRS amplitude in this lead); and iv) During my training I was always told if your accuracy in predicting acute appendicitis was greater than 80% — that meant that you were NOT referring enough acute RLQ pain patients to your friendly surgical colleagues. That’s because even the best diagnosticians on history and physical exam will not be able to predict with perfect accuracy which patients have acute appendicitis — so some patients who are appropriately explored may turn out to have a normal appendix. These percentages have of course changed with newer imaging techniques — but the corollary to acute chest pain patients remains — namely, that prompt cardiac catheterization IS appropriate on clinical grounds alone without diagnostic ECG signs in certain patients — even though some of those patients with turn out to have normal coronary arteries when the cath is done. This is one of the reasons caths are done — because sometimes you just need to PROVE whether this patient with chest pain who is in front of you, does or does not have not acute coronary disease. THANKS again to Dr. Smith for presenting this highly insightful case!ECG Interpretationhttps://www.blogger.com/profile/02309020028961384995noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-26104100143119962422018-02-05T21:14:08.970-06:002018-02-05T21:14:08.970-06:00Great teaching case and well-presented! A cardiolo...Great teaching case and well-presented! A cardiology attending of mine during residency used to refer to aVL as the "eVL" ("evil") lead. A subtle finding that I noted was that the ST segments in aVL (and also eventually in Lead I) were flat and the T waves were very symmetrical. I think that at times not enough attention is given to those findings - especially in the scenario of a patient with credible chest pain.<br /><br />As for the renaming of "posterior" infarctions as "lateral," don't make the "old-timers" mistake of thinking "but that's not the way we always did it!" There is a difference between the anterior surface of the heart and the suface of the heart that is located anteriorly. Perloff made a mistake when he made the unwarranted assumption that the posterior surface of the heart aligned with the posterior surface of the chest (though that shouldn't detract from the very significant contribution he made to ECG diagnosis!). What we thought of as "posterior" infarctions really are located in the basal LATERAL wall of the left ventricle. The heart is normally rotated in the chest so that the basal lateral wall of the LV is facing - for the most part - posteriorly in the chest. The old "true posterior" area can still infarct, but it will be manifested around V3 or V4 (and not well seen, either). I have not seen any references that state the lateral infarctions should be called "inferior" MIs. Initially ALL inferior MIs were called "posterior" MIs. Then we began distinguishing between lower posterior ("diaphragmatic" or "inferior") MIs and upper posterior MIs (near the base of the heart). Those eventually became known as "true posterior MIs" and the rest were "inferior" MIs. The mistake was assuming that the heart was aligned with the same topography as the chest cavity. It isn't!<br /><br />I totally agree with doing V7 - V9 leads when the patient has chest pain and a non-diagnostic ECG. The LCx tends to irrigate areas of the heart that are not well-covered by the standard recording electrodes.Jerry W. Jones, MD FACEP FAAEMhttps://www.medicusofhouston.comnoreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-34077250429333445232018-02-05T10:40:09.634-06:002018-02-05T10:40:09.634-06:00Wonderful case and wonderful discussion.Wonderful case and wonderful discussion.Dr.Rajiv Arorahttps://www.blogger.com/profile/11328692379948981426noreply@blogger.com