tag:blogger.com,1999:blog-549949223388475481.post2785703002714237125..comments2024-03-28T14:02:08.119-05:00Comments on Dr. Smith's ECG Blog: Diffuse Subendocardial Ischemia on the ECG. Left main? 3-vessel disease? No!Unknownnoreply@blogger.comBlogger12125tag:blogger.com,1999:blog-549949223388475481.post-12852425113162166742017-01-11T07:45:41.727-06:002017-01-11T07:45:41.727-06:00Ken,
That sounds correct, but I'm not totally ...Ken,<br />That sounds correct, but I'm not totally certain that the duration of systole does not shorten in tachycardia (again, it sounds correct, but I don't know of any data on it -- do you?)<br />SteveSteve Smithhttps://www.blogger.com/profile/08027289511840815536noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-26143443003236625332017-01-08T14:03:12.641-06:002017-01-08T14:03:12.641-06:00And that explains why tachycardia is bad for the b...And that explains why tachycardia is bad for the blood/oxygen supply to the myocardium - with increasing heart rate the systole duration still remains more or less constant, it's the duration of the diastole which decreases. So the duration of blood flow to the myocardium (diastolic) decreases with increasing heart rate. Correct?Alexander Dejaconoreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-37113127512290158192016-12-02T10:29:58.790-06:002016-12-02T10:29:58.790-06:00No. When the LV is contracting, it has to have hig...No. When the LV is contracting, it has to have higher pressure than the LV chamber in order to pump that blood. And the LV chamber must be higher than the aortic pressure for there to be a gradient to pump. therefore, the systolic intramyocardial pressure is higher than arterial pressure and there is no flow during systole. In the RV, there is flow during both systole and diastole.Steve Smithhttps://www.blogger.com/profile/08027289511840815536noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-20693144292263223232016-12-02T00:16:23.032-06:002016-12-02T00:16:23.032-06:00Dr. Smith, thanks as always for your great posts. ...Dr. Smith, thanks as always for your great posts. Under the section 'Oxygen Supply' you write that all coronary blood flow happens during diastole. But I though right heart perfusion occurred during systole as well as diastole because the right heart chamber pressures in systole are much lower than left heart chamber pressures during systole. Is this not correct? Thanks, KenKenhttps://www.blogger.com/profile/13631165950324445670noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-73906204828942077422016-12-02T00:10:15.203-06:002016-12-02T00:10:15.203-06:00Dr. Smith, thanks as always for your great posts. ...Dr. Smith, thanks as always for your great posts. Regarding your comment under "Oxygen" - 'all coronary flow happens during diastole because intramyocardial pressure during systole stops blood flow' - I thought the left heart coronaries only perfused during systole but the right heart coronaries perfused during systole and diastole because the right heart chamber pressure was lower. Is this not correct?Kenhttps://www.blogger.com/profile/13631165950324445670noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-32157954382909481842016-11-23T12:15:29.587-06:002016-11-23T12:15:29.587-06:00Okay, thank you!Okay, thank you!Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-47901138192237344552016-11-23T10:58:46.306-06:002016-11-23T10:58:46.306-06:00There is no evidence of LVH and the ST-T abnormali...There is no evidence of LVH and the ST-T abnormalities are nothing like what is seen in LVH.<br />Onc you've seen a lot more ECGs, you'll see what I mean.<br />Steve SmithSteve Smithhttps://www.blogger.com/profile/08027289511840815536noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-65507596247623925122016-11-23T09:18:50.810-06:002016-11-23T09:18:50.810-06:00Hi Dr. Smith:
I am a first year medical student, ...Hi Dr. Smith:<br /><br />I am a first year medical student, and I have been studying ECGs on my own. In this scenario, would it have been possible to suspect LVH in the patient based on the ECG alone? The voltage criteria are not entirely met, but there seems to be ST depression and T wave inversion in the lateral leads. Or would the right axis deviation counter-indicate LVH? My knowledge is still very limited, so I apologize if there is a very obvious answer to this question.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-81909741726543943562016-11-21T14:45:43.842-06:002016-11-21T14:45:43.842-06:00You have to read everything, not skim. Look at wha...You have to read everything, not skim. Look at what it says:<br />Smith comment:<br />This patient did not have a bedside ultrasound. Had one been done, it would have shown a feature that is apparent on this ultrasound (however, this patient's LV function would not be as good as in this clip):Steve Smithhttps://www.blogger.com/profile/08027289511840815536noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-74752326200954020152016-11-21T14:44:38.387-06:002016-11-21T14:44:38.387-06:00This patient had balloon valvuloplasty. Balloon p...This patient had balloon valvuloplasty. Balloon pump might have been useful as well.Steve Smithhttps://www.blogger.com/profile/08027289511840815536noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-31932738591377231532016-11-20T09:03:39.502-06:002016-11-20T09:03:39.502-06:00But EF seems to be normal in the above performed e...But EF seems to be normal in the above performed echo. Where is the EF of less than 15%??Anonymoushttps://www.blogger.com/profile/11105730908465882894noreply@blogger.comtag:blogger.com,1999:blog-549949223388475481.post-81857689066774282502016-11-19T15:13:36.869-06:002016-11-19T15:13:36.869-06:00Just a note, you comment on the patient having a b...Just a note, you comment on the patient having a balloon valvuloplasty but in the description it describes an inter-aortic balloon pump.CLM1https://www.blogger.com/profile/11606588162552119706noreply@blogger.com