tag:blogger.com,1999:blog-549949223388475481.post6870426045615206536..comments2024-03-28T14:02:08.119-05:00Comments on Dr. Smith's ECG Blog: A fast narrow complex rhythm.Unknownnoreply@blogger.comBlogger11125tag:blogger.com,1999:blog-549949223388475481.post-77735199898262860772017-09-12T15:20:41.830-05:002017-09-12T15:20:41.830-05:00Either one can have PVCs. It is the variable rate...Either one can have PVCs. It is the variable rate that makes PSVT so unlikely.Steve Smithhttps://www.blogger.com/profile/08027289511840815536noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-78573153454455752432017-09-12T15:02:02.113-05:002017-09-12T15:02:02.113-05:00Yes. Just withdrawal of the toxin and watchful wa...Yes. Just withdrawal of the toxin and watchful waiting was all that was necessary. The patient recovered fine.Steve Smithhttps://www.blogger.com/profile/08027289511840815536noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-19884461213544758142017-09-12T14:59:57.959-05:002017-09-12T14:59:57.959-05:00See these cases and decide for yourself: http://hq...See these cases and decide for yourself: http://hqmeded-ecg.blogspot.com/search/label/Lewis%20LeadSteve Smithhttps://www.blogger.com/profile/08027289511840815536noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-86541815739550849992017-09-12T14:58:13.508-05:002017-09-12T14:58:13.508-05:00Jerry,
We did not have tracings at all moments. T...Jerry,<br />We did not have tracings at all moments. The rate did vary. Although of course junctional tach is rare and usually associated with cardiac surgery or digoxin, it can also be associated with sympathomimetic toxins, which was the case here. Without intracardiac tracings, I cannot be certain of the diagnosis. It would be the first junctional tach I have ever diagnosed, but I'm still pretty sure that is what it was.<br />Thanks!<br />SteveSteve Smithhttps://www.blogger.com/profile/08027289511840815536noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-22658005885306543222017-09-08T05:22:31.540-05:002017-09-08T05:22:31.540-05:00Steve...
Sorry. I didn't see the information ...Steve...<br /><br />Sorry. I didn't see the information about the ephedrine ingestion. If the ephedrine level was somewhat variable, that could explain a changing junctional rate but still without autonomic NS involvement. Without that, however, I would not expect an automatic junctional tachycardia to vary except at the onset and offset of the dysrhythmia.Jerry W. Jones, MD FACEP FAAEMhttps://www.blogger.com/profile/10333187745825224414noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-38500886497029163012017-09-07T22:38:21.030-05:002017-09-07T22:38:21.030-05:00Steve...
A great teaching case. My thoughts are: ...Steve...<br /><br />A great teaching case. My thoughts are: The paramedics' ECG is unquestionably a typical, counterclockwise atrial flutter with a very interesting finding - an F wave alternans. I have seen this before but it is quite unusual and well worth saving for teaching purposes. The atrial rate is somewhere between 250 and 300/min. As for the other ECGs, I would certainly agree that they do not look like atrial flutter at all - the rate is much too slow. You speak of a rate that gradually changes but you must not have posted those tracings. Everything I see here is very precise and regular (except for the PVC). As to the origin of the non-flutter tracings, an automatic junctional tachycardia is certainly a possibility, though quite a rarity. You mention an automatic rhythm that is constantly varying which would not be typical of any automatic rhythm other than a sinus rhythm. Enhanced and abnormal automatic rhythms may have a warm-up and a cool-down as they begin and end (respectively), but once the rhythm gets going it's as regular as any re-entrant rhythm. An automatic junctional rhythm would not be subject to the same influence of the autonomic nervous system (though the adrenals could have an effect!). An automatic junctional rhythm would be a rarity in an adult unless the patient were digtoxic or had just had surgery for a congenital heart problem. In addition, while a junctional pacemaker focus may switch to another focus with a different rate, this would not result in a constant, gradual change. If the rate were under 150/min and the rhythm constantly and gradually changing, I would look for more evidence of P waves hidden in the T waves due to a first degree AV block.<br /><br />I agree that one should never have mistaken ANY of these rhythms for atrial fibrillation. As far as any analogy with sinus tachycardia, sinus tachycardia is almost always physiologic while junctional tachycardia is always pathologic.Jerry W. Jones, MD FACEP FAAEMhttps://www.blogger.com/profile/10333187745825224414noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-26401739476333232892017-09-06T15:25:13.324-05:002017-09-06T15:25:13.324-05:00I find lewis leads very interesting as a concept, ...I find lewis leads very interesting as a concept, but for the sake of treatement, does it really matter? I mean, should we avoid vagotonic monouvres, adenosine, calcium bloquers or Bbloquers if P waves are present?<br />Thankyou for this blog. It is really enlightning!Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-81614791352633767162017-09-06T03:07:10.373-05:002017-09-06T03:07:10.373-05:00Any follow- up, just wondered..Is it enough just t...Any follow- up, just wondered..Is it enough just to discontinue digoxin in these cases and wait-watch what happens Dr Smith ?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-28500763375953181572017-08-31T15:54:23.665-05:002017-08-31T15:54:23.665-05:00Thanks a lot
Can we depend on the presence of the ...Thanks a lot<br />Can we depend on the presence of the PVCs to differentiate junctional tachycardia from PSVT ?<br />Thanks againTareknoreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-38392333593848290382017-08-30T19:50:44.294-05:002017-08-30T19:50:44.294-05:00Thanks a lot ..
Can we rely on the presence of the...Thanks a lot ..<br />Can we rely on the presence of the PVCs to differentiate junctional tachycardia from PSVT ?<br />Thanks againTareknoreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-68479721343832747502017-08-30T18:17:39.946-05:002017-08-30T18:17:39.946-05:00Nice.... Great pointers for learning. ThanksNice.... Great pointers for learning. ThanksAnonymoushttps://www.blogger.com/profile/16407518463033899707noreply@blogger.com