tag:blogger.com,1999:blog-549949223388475481.post983567602160498414..comments2024-03-28T14:02:08.119-05:00Comments on Dr. Smith's ECG Blog: Weakness, head trauma, and an abnormal ECGUnknownnoreply@blogger.comBlogger4125tag:blogger.com,1999:blog-549949223388475481.post-33807204286372875742018-12-22T08:59:23.435-06:002018-12-22T08:59:23.435-06:00Probably "incomplete" RBBB. Although th...Probably "incomplete" RBBB. Although the ECG does not have great resolution, I believe the QRS duration is < 120 msSteve Smithhttps://www.blogger.com/profile/08027289511840815536noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-13427227082208312902018-12-21T18:24:55.041-06:002018-12-21T18:24:55.041-06:00would it be safe to diagnose incomplete rbbb also ...would it be safe to diagnose incomplete rbbb also hereAnonymoushttps://www.blogger.com/profile/16771433393519451427noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-23642968630294266372018-06-02T01:27:23.470-05:002018-06-02T01:27:23.470-05:00thank you to the "three ecg-kateers".
an...thank you to the "three ecg-kateers".<br />another cool case.<br />am awaiting Pendell's blog on the head trauma-ekg cases.thomas fieronoreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-28085975757600346972018-05-27T12:26:16.336-05:002018-05-27T12:26:16.336-05:00Excellent example of hypokalemia presented by Drs....Excellent example of hypokalemia presented by Drs. Meyers & Smith. I think the 3 of us each recognized within no more than 2-3 seconds the high likelihood of hypokalemia as probable cause for the ECG abnormalities on this tracing. That said, I’ll play a bit of “Devil’s Advocate”, while adding the following points. i) The principal ECG finding in this ECG with sinus bradycardia (rate just under 60/minute) is a markedly long QT (or QU) interval. The OTHER findings are ST segment flattening with slight depression in multiple leads (with ST elevation in leads aVR and V1) — AND — incomplete RBBB, with a Q in V1 and that slight ST elevation in this lead. RBBB morphology is suggested by the QR in V1 in association with narrow terminal s waves in leads I and V6 (with the QRS not being wide enough for this to be complete rbbb). ii) The causes of a LONG QT (or QU) INTERVAL — makes up one of my “LISTS” — whereby the interpreter’s life is simplified by remembering to consider the most common causes of a Long QT/QU = 1-Drug effect; 2-Electrolyte abnormality (ie, low K+/low Mg++/low Ca++); and 3-CNS catastrophe (ie, stroke, seizure, coma, tumor, trauma, bleed, etc). Ischemia/Infarction/Conduction defects are other common reasons for seeing a long QT/QU — but these entities will usually be suggested by other associated findings on the ECG. When the ONLY thing wrong with an ECG is a long QT/QU — Think Drugs/Lytes/CNS, or some combination of these as the cause. iii) As per Dr. Meyers — this ECG just “looks” like moderate-to-severe hypokalemia — because of the very long QT/QU with ST flattening and slight depression in multiple leads + large U waves. There is no obvious history for coronary disease, and lab tests will quickly confirm serum K+ & serum Mg++ status. But one should ALSO entertain in the differential diagnosis the possibility of contribution to these ECG abnormalities from ischemia (there is after all, diffuse ST depression with ST elevation in aVR) and/or CNS disturbance (this patient HAS been “falling”, which DID result in head trauma). This does NOT necessarily mean that troponin and CT scanning are immediately (or at all) needed — but rather that the BEST way not to miss a subtle diagnosis (ie, more than just electrolyte imbalance might be wrong with this patient … ) — is to start with a broad differential diagnosis, and to individualize considerations based on patient presentation/full exam/serial follow-up. iv) I favor obtaining at least a few serial ECGs on this patient as he is being treated. Chances are electrolyte imbalance is the primary (and perhaps only) cause of these ECG abnormalities. With K+ (and Mg++ if needed) replacement — I’d expect ST-T wave flattening and ST depression to get significantly less — and one will probably begin to see clear separation of the fused T-U wave into distinct T wave and U wave components — and you’ll have more opportunity to better assess if weakness from low K+ was the cause of the falls, or if there might also be some underlying neurologic problem … THANKS again to Drs. Smith and Meyers for presenting this insightful case!ECG Interpretationhttps://www.blogger.com/profile/02309020028961384995noreply@blogger.com