Tuesday, December 11, 2018

Found comatose with prehospital ECG showing "bigeminal PVCs" and "Tachycardia at a rate of 156"

This patient with a history diabetes was found with a GCS of 4.

Prehospital EKG and strips (not shown) had "heart rate 156" (according to the computer interpretation) and "Bigeminal PVCs"

The prehospital 12-lead looked just like the first ED ECG:
What do you think?

Answer: The "bigeminal PVCs" is really a QRS followed by a very narrow peaked T-wave, which was so narrow that it was mistaken for a separate QRS.  The heart rate is 78, not 156.  Notice also the very long ST segment, most easily seen in inferior leads.

This ECG is pathognomonic for severe hyperK, and the long ST segment is all but pathognomonic for hypocalcemia. So I knew immediately that the patient needed a lot of IV calcium, and, based on the prehospital ECG, we gave 6 grams of calcium gluconate before even drawing blood for lab values.

When we did get a chem back (drawn after 6 g Ca gluconate), the K was 9.0 mEq/L and the ionized calcium was not reported because it was too low.

The patient had a glucose of 1400, was severely dehydrated, and after receiving 4 liters of fluid, albuterol, and insulin, the K had dropped precipitously to 5.8 and the ECG improved:

The Calcium AFTER 6 g of treatment was 8.2 mg/dL.

Cr was 8.0 (previous was normal).  The patient had hyperK due to acute renal failure.

Learning Points:

1. Learn all the different pathognomonic ECGs of severe, life threatening hyperK.
2. A long ST segment is typical of hypocalcemia
3. Immediate treatment of HyperK is calcium. It is safe even when there is no hypocalcemia, but is particularly safe if there is hypocalcemia, which you can infer from a long ST segment.

Comment by KEN GRAUER, MD (12/11/2018):
I love this case — because it brings home 3 of my favorite teaching points about electrolyte disorders and ECG interpretation. For illustrative purposes — I’ve put both tracings in this case together in Figure-1.
Figure-1: The 2 ECGs in this case (See text). 
Teaching Point #1: You can sometimes make the diagnosis of acute DKA (Diabetic KetoAcidosisfrom an ECG, even before blood values come back! If the clinical setting is “right” (ie, an acutely ill patient with a history of diabetes, or impaired mentation with Kussmaul respiration) — and, the initial ECG suggests marked hyperkalemia — then acute DKA should be immediately considered.There just aren’t that many clinical conditions that cause hyperkalemia. Among the most common entities are:
  • Renal failure (acute or chronic).
  • Severe acidosis.
  • Use of K+-retaining medications or K+ supplementation (especially if the patient has underlying renal impairment).
  • Severe dehydration.
  • Addison’s disease (adrenal insufficiency) — which is not common ...
  • Destruction of red blood cells due to trauma, severe injury or burns.
COMMENT — An ECG can often be obtained in the ED before lab values come back. If the tracing suggests significant hyperkalemia — then think of the above entities as you correlate clinically to the patient in front of you in your search for a cause. Considering that acute DKA often presents with 3 of the above causes of hyperkalemia (ie, severe acidosis, renal impairment, and dehydration) — acute DKA should be high on your list unless another etiology is obvious.
Teaching Point #2: The typical ECG picture of hypocalcemia is a long, relatively normal (and typically isoelectric) ST segment — at the end of which is a relatively normal T wave (unless the T wave is altered by another disorder, such as hyperkalemia).
  • Although the ST segment manifests abnormal coving in multiple leads in ECG #1 (Figure-1) — ST segments are strikingly prolonged without obvious elevation or depression — and only then … comes the T wave. As per Dr. Smith, the pointedness and narrow base of T waves in virtually every lead in ECG #1 is the result of hyperkalemia.
COMMENT — Hyperkalemia and hypocalcemia often occur together in renal failure. This makes it easier to suspect associated hypocalcemia when a hyperkalemic-looking ECG shows an unexpectedly prolonged ST segment prior to the peaked T waves.
Teaching Point #3: There is a REASON why the initial ECG ( = ECG #1 in Figure-1in this case looks highly unusual! By this I mean that although T waves are clearly pointed and peaked with a narrow base — we don’t usually see biphasic T waves in hyperkalemia, as are present in leads V1-thru-V6!

QUESTION: Why do the T waves in ECG #1 look so strange that they were mistaken for PVCs?

ANSWER: The effect of hyperkalemia on the ECG is additive to (superimposed onhowever the baseline ECG looked! This fundamental point is all-too-often ignored!
  • IF the baseline ECG is relatively normal — then development of severe hyperkalemia will produce a picture of tall, peaked and pointed T waves with a narrow base — ultimately resulting in loss of P wave amplitude, bradyarrhythmias, and QRS widening.
  • BUT — IF the baseline ECG is abnormal, with preexisting ST-T wave depression — then the degree of T wave peaking from hyperkalemia may be significantly attenuated.
  • FINALLY — IF the patient presenting with hyperkalemia is also acutely ischemic — these ischemic ECG changes may not be recognizable until serum K+ is normalized and the ECG is repeated.
COMMENT — The ECG after treatment in this case is the bottom tracing in Figure-1 ( = ECG #2). It should be emphasized that serum K+ was not yet normal at the time ECG #2 was recorded (serum K+ = 5.8 mEq/L) — so we are not privilege to a true “baseline” tracing for this patient. That said, it is clear that fairly deep, symmetric T wave inversion is present in leads V3, V4 and V5 of ECG #2 — with at least suggestion of abnormal ST segment coving in these leads. Whether these ST-T wave abnormalities in ECG #2 are new (and whether they might be even more pronounced if the ECG was repeated after complete resolution of electrolyte disorders) is uncertain. BOTTOM LINE: Seeing ECG #2 explains the highly unusual picture of ST segment coving with biphasic T waves that was seen in the initial ECG ( = ECG #1) when serum K+ = 9.0 mEq/L.
  • P.S.  Did you notice that the QRS complex in ECG #1 is wide? (ie, it appears to be at least 0.12 second in duration in leads V2,V3,V4). That this QRS widening in ECG #1 is real, and is the result of marked hyperkalemia is verified by the presence of a decidedly more narrow QRS complex in ECG #2 after treatment.
Final NOTE: Did you recognize that the rhythm in ECG #2 is not simply sinus? If not — then you weren’t systematic in your interpretation.
  • PEARL  The easiest way to never overlook a non-sinus rhythm — is to always begin your interpretation of any ECG by spending a quick 2-3 seconds surveying every beat in the long lead II rhythm strip. If you do not see an upright P wave with fixed PR interval preceding each QRS complex — then the rhythm is not strictly sinus. The only 2 exceptions to this rule are lead misplacement and dextrocardia.
QUESTION: What then is the rhythm in ECG #2 of Figure-1?

ANSWER: The rhythm in ECG #2 is complex. The important point — is to recognize that because the initial beats in the long lead II rhythm strip are not preceded by an upright P wave (BLUE arrows in Figure-2) — this can’t be a sinus rhythm (assuming no dextrocardia or lead misplacement).
  • Admittedly, assessment of the rhythm in ECG #2 is complicated by baseline artifact and the low amplitude of atrial activity. That said — there should be NO doubt that the P wave preceding the first 9 beats is negative in lead II (BLUE arrows), as well as in the other inferior leads. A small upright P wave does appear to be present in front of the QRS in lead I. This suggest this is a coronary sinus rhythm.
  • Beat #10 is early. It is a PAC.
  • Sinus rhythm clearly resumes for the last 4 beats on this tracing (ie, beats #13-16) — as each of these beats is preceded by a small-but-clearly-upright P wave with a fixed and normal PR interval (RED arrows).
  • Sinus P waves also appear to precede beats #11 and 12 (RED arrows) — but the PR interval preceding these 2 beats is short, suggesting they are junctional escape beats.
Figure-2: We have labeled ECG #2 to explain the rhythm (See text).
Clinically — Brief appearance of a coronary sinus rhythm until a PAC reset the sinus pacemaker did not affect outcome in this case. My purpose in discussing the rhythm in ECG #2 was simply to highlight how easy it is to overlook subtle arrhythmias if one is not meticulous and systematic. Failure to do so may affect clinical outcome in other cases ...

Wednesday, December 5, 2018

Two cases of ST Elevation with Terminal T-wave Inversion - do either, neither, or both need reperfusion?

Written by Pendell Meyers with edits by Steve Smith

I was sent these 2 ECGs with no clinical information other than chest pain:

Do either or both of these ECGs show ischemic changes? If so, what should you do and why?

Let's take them one at a time.

What would your response be?

I responded: "Awesome classic benign T wave inversion! That's the patient's baseline normal variant. ... But if it were a good story with exertional syncope or something you'd have to treat it like it could be HOCM, etc. Tell me more."

There is sinus rhythm with very large voltage and associated repolarization abnormalities. In V3-V6 there are classic and dramatic findings of BTWI including small or no S-waves, large R-waves, pronounced J-waves, ST-elevation, and steep dramatic T-wave inversions, all with a short QT interval.

Later, I was told this history:

The patient was a 17 year old African American male with history of asthma who presented with chest tightness and shortness of breath for 6 hours. He improved almost completely after a duoneb (albuterol and ipratropium). However the clinicians were surprised by his unusual ECG findings. 

He had no prior ECG on file. He had no family history of cardiac issues or sudden death. Labs were normal, including troponin x2. He is able to play basketball routinely without any issues.

In the ED he had a CT angio which was negative for aortic dissection. He was admitted for observation and cardiology consult. He had a normal CT coronary angiogram, as well as a normal cardiac echo. Serial troponins were negative.

Smith Comment: Although this ECG pattern is not ischemic, it may sometimes be seen in individuals with hypertrophic cardiomyopathy. For this reason it may be prudent to obtain an echocardiogram in these patients before they are allowed to engage in vigorous athletic activity. [1,2]

Let's return to the other case:

There is sinus rhythm with QS-waves in V1-V3. There is ST elevation in V1-V3 as well, with convex appearance and some terminal T-wave inversion. 

I advised the team that the patient has had a large anterior MI, but I cannot tell how long ago it occurred. It could be 6-12 hours after completion or reperfusion of anterior MI, or it could be days to years after the event. I advised them that I do not see any signs of reocclusion on this ECG, meaning that I do not think this ECG at this time represents acute LAD occlusion that would benefit from emergent reperfusion.

Let's use the LV aneurysm rule on this ECG to see if it supports our theory:

Here is the rule, which should be used if there is suspicion of aneurysm (there are Q-waves in V1-V4, especially QS waves): "If there is one lead of V1-V4 with a T/QRS ratio greater than 0.36, then it is acute MI. If less than 0.36, it is either subacute (over 6 hours) or old." [3,4]

V1 = 2/10 = 0.20
V2 = 2/12 = 0.17
V3 = 1.5/7 = 0.21

So it agrees with our visual subjective interpretation that this is either subacute or old.

I later found out that the patient had history of an LAD occlusion MI two months ago, with a stent placed.

He was taken for emergent cath due to his history and the ECG findings including ST elevation (although ST elevation is a terrible way to distinguish ischemia from non-ischemia). 

His cath showed perfectly patent stents.

Three serial troponins were undetectable.

His serial ECGs did not change.

He was discharged home.

Learning Points:

There are many causes of ST elevation, terminal T-wave inversions, and both simultaneously. Experience with the cases on this blog can teach you how to differentiate them.

Wellens syndrome (or reperfusion in general) is an important cause of terminal T-wave inversions. See these cases below for examples. However, Wellens' syndrome includes resolution of chest pain and preservation of R-waves, in addition to T-wave inversion. Thus, this second case would not be an example of Wellens' syndrome.

Classic Evolution of Wellens' T-waves over 26 hours

Also see below for more cases of LV aneurysm morphology:

Tachycardia and ST Elevation.


T/QRS ratio to differentiate anterior STEMI from anterior LV aneurysm:
1. Papadakis M, Carre F, Kervio G, et al. The prevalence, distribution, and clinical outcomes of electrocardiographic repolarization patterns in male athletes of African/Afro-Caribbean origin. Eur Heart J. 2011;32(18):2304-2313. doi:10.1093/eurheartj/ehr140

2. Wells S, Rowin EJ, Bhatt V, Maron MS, Maron BJ. Association Between Race and Clinical Profile of Patients Referred for Hypertrophic Cardiomyopathy. Circulation. 2018;137(18):1973-1975.

Comment by KEN GRAUER, MD (12/5/2018):
It’s always great practice to be given tracings and “Put to the Test” as to whether you think acute changes are, or are not present. I came to the identical conclusion as did Drs. Smith & Meyers about the 2 ECGs in this case — albeit via a slightly different intuitive pathway. For clarity — I repeat the tracings in Figure-1.
Figure-1: Two ECGs we are asked to assess, but without benefit of any history (See text).
ECG #1:
  • Knowing some History is KEY. As per Dr. Meyers — If the history of this patient was worrisome, then the onus of “proof” still rests upon us to prove there are no acute ECG changes, rather than the other way around. REMEMBER — Patients with early repolarization on their baseline ECG may develop superimposed changes of acute STEMI, that can at times be difficult to discern because of pronounced baseline benign ST-T wave repolarization changes.
  • That said, in addition to the benign-appearing findings described in detail by Drs. Meyers & Smith — I thought these findings in ECG #1 were probably not acute because: iThe Q waves in the inferolateral leads are very small (these look like normal septal q waves in a patient like this with an inferior frontal plane axis); iiThere is no reciprocal ST depression; iiiExcept for lead V3 — the leads with the deepest T inversion manifest the tallest R waves; andivLead V3 is perfectly consistent with being a transition lead” (ie, V3 looks precisely as I’d expect for a lead located in between the upright T wave and predominantly negative QRS seen in V2 — and — the huge R wave with deep T inversion in V4).
  • The ECG appearance of patients with hypertrophic cardiomyopathy (HCMis highly variable. Among potential ECG findings in such patients are LBBB, RBBB, IVCD, large Q waves in multiple leads (especially in lateral and/or inferior leads); prominent septal forces (ie, relatively tall R waves in anterior leads) — and/or marked increase in QRS amplitude in various leads with notable ST-T wave abnormalities (as are seen here in ECG #1). And sometimes, the ECG of patients with hypertrophic cardiomyopathy is surprisingly unremarkable. TAKE-HOME Point: The prominent QRS voltage and marked ST-T wave abnormalities in ECG #1 should clearly prompt consideration of possible HCM. An Echo is indicated if there is any concern.
ECG #2:
  • Knowing some History is KEY. As per Dr. Meyers — the correct clinical interpretation of ECG #2 is, “Anterior MI of uncertain age, possibly recent” — with need for clinical correlation.
  • Reasons we KNOW there has been prior anterior MI in ECG #2 include the following — iThere is a fragmented initial Q wave deflection in lead V3 (and when you see this initial fragmented qrS deflection — it is highly suggestive of true prior infarction); iiThere is loss of r wave (a tiny r looks to be present in V1 — but it is wiped out by the q wave in V3)iii) The q wave in V4 shouldn’t be there (because this q in V4 is larger than the tiny q in V5 — and it looks like there is no q in V6); and, ivST coving and T inversion is most prominent in the anterior leads that manifest abnormal initial (q wave) deflections.
  • Reasons for suspecting that even if ECG changes in ECG #2 were to be recent — they probably do not reflect acute coronary occlusion, include the following — iIt usually takes a little time to develop the fragmentation and the amount of lost anterior forces as is seen in leads V1, V2 and V3 of ECG #2; and, iiThe amount of ST elevation in the anterior leads is modest compared to significant loss of anterior forces and the extent of T wave inversion. NOTE: Exceptions always exist, and it is possible to develop the ECG picture seen in ECG #2 over a fairly short period of time … — BUT  “the look” of this tracing is such that I thought the changes in ECG #2 were probably not acute.

Friday, November 30, 2018

The 4 Physiologic Etiologies of Shock, and the 3 Etiologies of Cardiogenic Shock

A 60-something presented with hypotension, bradycardia, chest pain and back pain.

She had a h/o aortic aneurysm, aortic insufficiency, peripheral vascular disease, and hypertension.  She had a mechanical aortic valve.  She was on anti-hypertensives including atenolol, and on coumadin, with an INR of 2.3. 

She was ill appearing.  BP was 70/49, pulse 60.

A bedside echo showed good ejection fraction and normal right ventricle and no pericardial fluid.

Here is the initial ECG:
What do you think?

This ECG actually looks like a left main occlusion (which rarely presents to the ED alive):  ST Elevation in aVR, but also in V1, and what appears to be "coving" of the ST segment in aVL, which suggests ST Elevation in that lead as well.

There is bradycardia, which is ominous in such a sick patient.  This may be due to atenolol, but could simply be a sign of severe illness.

Whereas ST elevation in aVR is usually reciprocal to the the ST depression of subendocardial ischemia, with a negative ST vector towards leads II and V5, and may be accompanied by STE in V1 (which is in the same direction as aVR), when there is also STE in aVL it implies a more directly superior ST axis (supported by ST depression in all of II, III, aVF).

When the ST axis is directly superior, there may actually be transmural ischemia of the "base" of the heart (the base is actually the top of the heart, which really does not have a wall -- the ventricles have openings to the atria at the base, and so no complete wall).  However, the anterior, lateral, posterior, and septal walls all have a superior portion that may result in ST elevation in a superior direction if all walls have subepicardial ischemia, as in left main occlusion.

It is important to remember that an ECG like this represents possible left main occlusion only if it is a result of ACS!! 

Knotts et al. found that such ECG findings only represented left main ACS in 14% of such ECGs: 
Only 23% of patients with the aVR STE pattern had any LM disease (fewer if defined as ≥ 50% stenosis). Only 28% of patients had ACS of any vessel, and, of those patients, the LM was the culprit in just 49% (14% of all cases).  It was a baseline finding in 62% of patients, usually due to LVH. 

Reference: Knotts RJ, Wilson JM, Kim E, Huang HD, Birnbaum Y. Diffuse ST depression with ST elevation in aVR: Is this pattern specific for global ischemia due to left main coronary artery disease? J Electrocardiol 2013;46:240-8.    

Case continued:

The chest X-ray was consistent with pulmonary edema, and the ultrasound showed a "plump" inferior vena cava.  (This data is all consistent with high right and left sided filling pressures, which is the hallmark of cardiogenic shock -- not obstructive, distributive, or hypovolemic)

Aortic dissection was considered (with involvement of the coronary arteries and aortic outflow obstruction), but a CT scan was negative for dissection.

The cath lab was activated.

It is a very long story, but I will make it brief:

The angiogram could not be done because of inability to access the arterial system (unexplained).

The interventionalist listened to the heart and heard both a systolic flow murmur across the valve and a diastolic murmur.

A formal echo showed aortic insufficiency, then TEE showed a mass on the aortic valve, and surgical exploration showed aortic valve thrombosis.  

This was not ACS.  This was not Left Main occlusion.


Shock has 4 basic etiologies:

1. Obstructive (pulm embolism, tension pneumothorax, tamponade, atrial myxoma, etc.)
These were all ruled out
2. Distributive (sepsis, neurogenic, beriberi, etc.).  The patient showed no signs of high output
3. Hypovolemic (dehydration, hemorrhage, third spacing)  The IVC was plump

4. Cardiogenic -- the likely culprit

Cardiogenic shock has 3 basic physiologic etiologies:

1. Poor pump function (diastolic or systolic)  The bedside echo showed good pump function, though that does not completely rule out diastolic dysfunction.
2. Dysrhythmia (too fast or too slow to adequately fill and pump)  There was only some mild bradycardia
3. Valvular.  The pump works but the blood goes the wrong way.  This is what we are left with: Valvular etiology is frequently forgotten.  Any valve dysfunction can result in shock, especially aortic, mitral, or tricuspid (I have never seen a case of acute pulmonic valve dysfunction and cursory search found nothing)

Aortic valve thrombosis should be considered in any patient who has a prosthetic aortic valve, especially a mechanical one.  It is a catastrophic complication, which is why we are so careful to maintain a high therapeutic INR on these patients.

One could say that this case is a hybrid of cardiogenic and obstructive shock, but since it is all valvular, let's call it cardiogenic.

Suffice it to say that one should suspect valvular thrombosis in patients with artificial valves who have:

1. Dyspnea
2. New or worsening heart failure
3. Hypotension or shock

One should listen for muffled heart sounds or a new murmur, but this is not sensitive.

One should be suspicious especially if the INR is not at the goal of:

2.5  - for bi-leaflet or current-generation single tilting disk mechanical aortic valves is 2.5 if they have no risk factors for thromboembolism 

3.0  - if they have a ball-cage mechanical valve (because of the associated higher risk of thrombosis) or risk factors for thromboembolism such as atrial fibrillation, left ventricular systolic dysfunction, prior thromboembolism or hypercoagulable state.

3.0  - (range, 2.5 to 3.5) for patients with mechanical mitral valves 
3.5 to 4.0 -  for patients with mechanical tricuspid valves. 
Transesophageal echo may be necessary for diagnosis.

Always think about doing Doppler on the valves during POCUS.  It is not that difficult to see regurgitation.  Had that been seen, the diagnosis would have been made much earlier.
Complications of aortic thrombosis include, of course, severe obstruction of aortic outflow (with shock), aortic insufficiency and regurgitation, and embolism to any artery in the tree, resulting in stroke, myocardial infarction, or other catastrophic infarction.
The combination of outflow obstruction (decreased cardiac output) and regurgitation (low diastolic pressure) results in severe coronary ischemia.  The coronaries are perfused during diastole when the myocardium is not contracting.
There is no reason to write more about this complication, as there are many good articles on the topic.  See this one:

Comment by KEN GRAUER, MD (11/30/2018):
Interesting case with an excellent discussion and timely reminder by Dr. Smith of the principal etiologies of shock and cardiogenic shock. I limit my comments to the initial ECG, which I’ve reproduced for clarity in Figure-1.
Figure-1: Initial ECG on a woman in her 60s, presenting with shock (See text). 
My interpretation of the ECG in Figure-1 was as follows:
  • Baseline artifact. This is most marked in leads I and III, suggesting the cause might be the right upper extremity.
  • Sinus bradycardia at a rate just over 50/minute. All intervals (PR, QRS, QT) are normal. Slight leftward axis, though not quite leftward enough to qualify for LAHB (since the QRS complex is still predominantly positive in lead II).
  • Probable LVH (See below).
  • Diffuse ST-T wave depression, with especially deep T wave inversion in leads V4-thru-6 — and biphasic T waves in leads III, aVF and V3. Significant ST elevation in leads aVR and V1, with fatter-than-they-should-be T wave peaks in these leads, and a pattern for the ST-T waves in leads aVR and V1 that looks “reciprocal” to the ST-T wave depression in many of the other leads.
IMPRESSION: Sinus bradycardia with probable LVH + ST-T wave changes suggestive of LV “strain” + diffuse subendocardial ischemia. Urge clinical correlation.
  • Why probable” LVHThe ECG is an imperfect tool for assessment of LVH. At best — sensitivity of the ECG for picking up LVH is no more than 55%. Echo is far superior to the ECG for assessment of chamber enlargement. That said, when the clinical situation is “right” — and, voltage criteria for LVH are met — and, ST-T wave repolarization changes of LV “strain” are present — then specificity of the ECG for detecting LVH may be more than 90-95%! Admittedly, voltage criteria for LVH are not met in Figure-1 (ie, the R wave in lead V6 falls shy of the 18-20 mm needed in this lead). But, given the high prevalence clinical situation (ie, this patient has known hypertension plus aortic insufficiency) + nearly enough R wave amplitude in lead V6 (16mm) + ST-T wave changes consistent with LV “strain” in all lateral leads (ie, leads I, aVL, V4-6) — true chamber LVH is likely (CLICK HERE  for more on the ECG diagnosis of LVH).
  • It would be extremely interesting to see a baseline ECG on this patient, taken at a time when she is not in acute cardiogenic shock! My GUESS as to what such a “baseline” ECG on this patient would show is: iST-T wave changes of LV “strain” in the same 5 lateral leads with similar shape for the ST-T waves, but with less J-point depression than the 2-4mm seen in leads V4-thru-V6 in Figure-1; iimuch less (if any) ST elevation in leads aVR and V1; iiipossibly an upright T wave in lead V2, with a shape reciprocal to the ST-T wave depression seen in the lateral chest leads in Figure-1 (ie, LV “strain” often results in mirror-image upright ST-T waves in anterior leads, compared to the ST-T depression seen in lateral chest leads); ivmuch less (if any) ST depression in leads II, III, aVF and V3 (with loss of biphasic T waves); and, v) possibly greater R wave amplitude in lateral chest leads (sometimes ischemia reduces R wave amplitude ... ).
  • Without the luxury of seeing this patient’s “baseline ECG” — we are reduced to educated guessing about which ECG findings in Figure-1 are “new” vs “old” vs “new on-top-of old”. My hunch is that what we are seeing in Figure-1, is a combination of longstanding LVH with LV “strain” superimposed diffuse subendocardial ischemia in this patient with acute cardiogenic shock from complications of her valvular heart disease. Cardiac catheterization would have told us if significant underlying coronary disease was also contributing to the subendocardial ischemia.
Our THANKS to Dr. Smith for presentation of this interesting case.

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