tag:blogger.com,1999:blog-549949223388475481.post285737681876888332..comments2024-03-26T22:42:04.176-05:00Comments on Dr. Smith's ECG Blog: Syncope and Prehospital Cath Lab activation -- What do you think?Unknownnoreply@blogger.comBlogger9125tag:blogger.com,1999:blog-549949223388475481.post-47263654362859546642020-02-11T21:29:23.723-06:002020-02-11T21:29:23.723-06:00THANKS for your comment Brian. I think you identif...THANKS for your comment Brian. I think you identified a KEY problem in your question — namely that there may be less emphasis on ECG interpretation education (for reasons that are also unknown to me) — and for whatever reason, there continues to be misuse of computerized ECG interpretations by placing too much confidence in them ... During my 30-year academic career — I taught a 2-week course to all medical students for 20 straight years — then the course was reduced to a mere 4 sessions for several years — and then eliminated entirely. And then we see interns with minimal ECG interpretation experience ... I don't have an explanation ...ECG Interpretationhttps://www.blogger.com/profile/02309020028961384995noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-65105403049968694052020-02-11T09:45:54.961-06:002020-02-11T09:45:54.961-06:00Dr Smith and Dr Grauer
As person who shares the s...Dr Smith and Dr Grauer<br /><br />As person who shares the same passion in ecg interpretation as both of you, do either of you have a recommendation on addressing the "many false positives" problem within pre hospital ecg's? This issue seems to be growing within the pre hospital community (my opinion) where industry is becoming very reliant on computer interpretation and less on education (for reasons unknown to me).<br /><br />I understand this is a big issue with many answers but was curious if this problem affects you (as physicians) as it does us as paramedics?<br /><br />BrianBrian Imdiekehttps://www.blogger.com/profile/12094550299651836241noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-89592627929464348772020-02-09T12:11:15.122-06:002020-02-09T12:11:15.122-06:00THANKS for your comment K! It relates to an issue ...THANKS for your comment K! It relates to an issue that a number of other readers have asked about regarding this post (such as the question just above you sent by "Unknown" on Feb. 8@ 2:42am). As you know — the cyclic pattern you describe whereby there is gradual change in the relative amount of preexcitation in a patient with WPW is known as the “Concertina Effect” — For interest, here’s another neat example of this phenomenon that was quite subtle (and which I did not initially see the 1st time I looked at this tracing) — http://ecg-interpretation.blogspot.com/2016/03/ecg-blog-121-arrhythmia-multiple-q.html — THANKS again (as always!) for your comments K! — :)ECG Interpretationhttps://www.blogger.com/profile/02309020028961384995noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-29901376729047239142020-02-08T15:45:07.810-06:002020-02-08T15:45:07.810-06:00Good discussions above. Additionally, the pre-exci...Good discussions above. Additionally, the pre-excitation can be intermittent. I have a good example of it in a book "Atlas of Electrocardiography by K Wang, page 209". There, at one moment, only every other beat is pre-excited, next moment, every beat is pre-excited, next moment, no beats are pre-excited.<br />K. Wang.Anonymoushttps://www.blogger.com/profile/04509940285330859355noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-47609173920902256822020-02-08T14:51:59.188-06:002020-02-08T14:51:59.188-06:00I addressed the seemingly short PR interval with s...I addressed the seemingly short PR interval with some initial slurring of the QRS in My Comment above. I DID initially consider the possibility of WPW. The fact is that in patients with WPW — there can be varying amounts of preexcitation — which on occasion may make it exceedingly difficult to detect a patient with minimal prexcitation (ie, with most of the electrical activity traveling over the noraml AV nodal pathway, instead of over the accessory pathway). In such cases — delta waves may be small, and only present in a few leads — and the QRS complex may not be wide or abnormal-looking. I cannot rule out that possibility in this case. That said — although the other 2 ECGs on this patient in this case suggested a relatively short PR interval — using the recommendation to select that lead where the PR interval looks longest, suggested to me that the PR interval was at least 0.12 second, which is the lower limit of normal (albeit in lead II, most of this 0.12 second is made up of P wave). I also did not see definite delta waves in the other 2 ECGs (some initial slurring of the QRS is NOT necessarily abnormal, and it is commonly seen in some leads in older patients). It sounds like there was NOT a prior history of arrhythmias in this patient (though details of his prior history are limited) — but IF true, it is less common for a worrisome arrhythmia to present for the 1st time in a WPW patient at the age of 61 (this patient’s age). Of course, without more information — it’s impossible to say for sure — but my hunch is: i) the history of a 10-second episode of “syncope” in this 61yo man with a history of ETOH abuse is probably not life-threatening; and ii) that this patient does not have WPW. One might search this patient’s chart for additional prior ECGs — since IF WPW is present, the relative amount of preexcitation may vary. On the other hand, if there are a bunch of additional prior ECGs on this patient — and if definite delta waves are NOT seen on any of them — then the chance that this patient has WPW is less. IF clinically indicated — additional evaluation could be undertaken — but I suspect it wasn’t needed in this case … IF you’d like MORE INFO on this subject — I thoroughly discuss it here — http://ecg-interpretation.blogspot.com/2018/07/ecg-blog-153-lvh-rvh-wpw-rbbb.html — I hope that helps answer your question — :)ECG Interpretationhttps://www.blogger.com/profile/02309020028961384995noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-73664693512236310182020-02-08T14:34:44.293-06:002020-02-08T14:34:44.293-06:00Regarding the Pre-Hospital ECG (ECG #1 in my Figur...Regarding the Pre-Hospital ECG (ECG #1 in my Figure 1) — as per Dr. Smith, it sometimes IS very difficult to distinguish with certainty between ischemic vs LV “strain” for the ST-T waves in the inferior leads. That said, in the context of the LACK of chest pain + lack of wall motion abnormality on bedside Echo — the SHAPE of the inferior lead ST-T wave depression (ie, slower downslope with faster return — as is most typical for LV “strain”) + the OVERALL picture of this ECG (ie, the chest leads look like LVH) — I thought it most likely that the inferior lead changes were also more likely due to LV “strain” than acute ischemia. The important Learning Point is that while LV “strain” (ie, ST-T wave repolarization changes consistent with LVH) is most commonly seen in one or more of the lateral leads (ie, leads I, aVL, V4, V5, V6) — LV “strain” may sometimes also be seen in inferior leads. Most often, inferior lead LV “strain” is seen when the frontal plane axis is relatively vertical — but despite a non-vertical axis in ECG #1 — I thought the combination of above features strongly suggested LV “strain” in this case. That said — when in doubt, cath may sometimes be needed …ECG Interpretationhttps://www.blogger.com/profile/02309020028961384995noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-23842385152974905802020-02-08T02:42:44.627-06:002020-02-08T02:42:44.627-06:00Dr Smith, how you explained syncopal episode? In t...Dr Smith, how you explained syncopal episode? In the pre hospital EKG I noted short PR with possible delta wave in infero lateral leads.. Your opinion? Thanks. Anonymoushttps://www.blogger.com/profile/16912754408039849199noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-84019390384256078742020-02-07T19:06:29.616-06:002020-02-07T19:06:29.616-06:00Very tough to answer. i was on the fence with thi...Very tough to answer. i was on the fence with this case and only decided not to activate the cath lab after seeing the old EKG, knowing the patient had no chest pain or SOB (he felt fine), and seeing the bedside echo. Most of the time, a patient with chest pain and this EKG should go to the cath lab unless echo can refute it.Steve Smithhttps://www.blogger.com/profile/08027289511840815536noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-47771202171933041172020-02-07T17:00:16.896-06:002020-02-07T17:00:16.896-06:00How can u differentiate then b/w Hyperacute T wave...How can u differentiate then b/w Hyperacute T waves (II, III & aVF) with LVH in this scenario (I mean pre-hospital ECG)Anonymousnoreply@blogger.com