Monday, September 19, 2022

This ECG is nearly pathognomonic. What is it? (hint: it's not Wellens')

I was texted this ECG:

What did I say?

My response: "takotusubo"

Even without a history, this is the likely diagnosis.  Later, I obtained the history: 60-something woman who presented with agitation and had taken a benzodiazepine overdose.  There was no report of chest pain.  She had a respiratory alkalosis, with venous pH of 7.56 (equivalent to an arterial pH of higher than 7.60 and possibly contributing to the long QT and ECG abnormalities).  Electrolytes were normal.   She was also on Duloxetine, which can prolong the QT, and on Lithium (but her level was very low).

This is almost certainly takotsubo.  The widespread bizarre T-wave inversion with very prolonged QT interval is classic for takotsubo cardiomyopathy. Most people will say "Wellens?" to this ECG, but the T wave inversions are too big, the QT too long and too bizarre for Wellens' (which is due to spontaneous reperfusion of OMI).  

Moreover, Wellens' would involve just one territory, and Wellens' of the LAD would be V2-V4 with possible extension to V5-V6 and to I, aVL if it is a proximal LAD lesion; but it could exend to II, III, aVF if it is an LAD that "wraps around" to the inferior wall ("wraparound, or Type III, LAD).  

By the way, this also resembles the "Spiked Helmet Sign," which is usually a manifestation of stress cardiomyopathy.  See this case: Spiked Helmet Sign

A bedside echo was done:
This shows apical ballooning consistent with takotsubo.  
But not all apical ballooning is takotsubo.  
An anterior and inferior OMI due to a wraparound LAD will result in the same findings.

An ECG was recorded 32 minutes later:

And another at 8 hours:

And another at 20 hours

And the last one at 41 hours:

Here was the final ECG at 72 hours:

QT interval is now normal

A formal echo was done at 48 hours:

Normal left ventricular size and systolic function with an estimated EF of 66%.

No regional wall motion abnormality.

Complete resolution

One would expect a peak troponin I between 1000 - 5000 ng/L (based on our experience, I don't think we have good data on this yet), but her peak was only 160 ng/L.

Learning Point:

Takotsubo comes in 2 primary forms: 

1. ST Elevation that mimics OMI of anterior, lateral, and inferior walls (usually due to a wraparound LAD) and is very difficult to distinguish from OMI without an angiogram.  The ST Elevation may exactly mimic OMI.  There is apical ballooning in both cases, so ultrasound will not help you!!  When the ST elevation has a bizarrely long QT, then takotsubo is more likely.

2. Diffuse T-wave inversion, usually with a long QT and looking somewhat bizarre.

In both cases, you get apical ballooning

When it is T-wave inversion, you need not worry so much about activating the cath lab because, if it is due to ACS, the T-wave inversion tells you that the artery is open (This is what Wellens' syndrome is all about)

So I was not worried that this might be an unusual case of ACS: if it is ACS, the cath lab does not need activating, a huge mass of myocardium is not at risk.

Here are more cases:

There are 2 general types of ECG presentation in takotsubo:

1. ST Elevation, often diffuse and not in one coronary distribution.

With this presentation, it is often necessary to obtain emergent angiography because what you think is takotsubo is often really STEMI/OMI.  Patients with occlusion of a wraparound (Type III) LAD that wraps around the apex such that it also supplies the inferior wall have diffuse ST Elevation and also have apical ballooning, such that you might think it is takotsubo.

See this case: 

Diffuse ST Elevation with Apical Ballooning: is it Takotsubo Stress Cardiomyopathy?

Examples of takotsubo with ST Elevation: 

Chest pain, sinus tachycardia, and ST Elevation

COPD exacerbation, what do the ECG and bedside echo show?

2. Bizarre T-wave inversions, in which case it could be ACS but does not need emergent angiogram to prove it.

See these cases of takotsubo with T-wave inversion:

Bizarre T-wave inversions, with Negative U-waves and Very long QT. And a myocardial viability study.

Comment by KEN GRAUER, MD (9/19/2022):
As I always do when Drs. Smith, Meyers or McLaren post a new Draft for upcoming use in Dr. Smith's ECG Blog — Before I write My Comment, I search for previous cases we've discussed on the Blog, so that I can reinforce concepts previously covered. 

So, when I did this for today's case — I came across our June 22, 2020 post on this subject. This post began very much in the way today's post begins. The 1st line written by Dr. Smith in our 6/22/2020 post read as follows: "This ECG was texted to me. My response was Takotsubo".
  • Dr. Smith wrote the following in the legend of this 6/22/2020 case as his rationale for his instant impression that the diagnosis was Takotsubo Cardiomyopathy: "There are diffuse T wave inversions — and a bizarre, very long QT interval. This is very typical of Takotsubo".

By way of review — I thought it may be helpful to review the initial ECG from today's case — which for clarity, I have reproduced in Figure-1.
  • The essence of Dr. Smith's assessment in today's case — is virtually the same as what he wrote for the 6/22/2020 case: "This is almost certainly Takotsubo. The widespread bizarre T-wave inversion with very prolonged QT interval is classic for Takotsubo Cardiomyopathy".

Figure-1: The initial ECG in today's case.

Giant T Waves and Takotsubo:
While I completely agree with Dr. Smith's assessment that the initial ECG in today's case strongly suggests Takotsubo Cardiomyopathy — I'd add the following:
  • In addition to the bizarre and markedly prolonged QTc in Figure-1 — there are Giant T Waves. As I discussed in My Comment in the June 22, 2020 post of Dr. Smith's Blog — I have found it helpful on recognizing the presence of truly deep (ie, >5-10 mm amplitude) T wave inversion — to consider the entities listed in Figure-2. Given that depth of the T waves in leads V3 and V4 of Figure-1 attain 18 and 20 mm, respectively — today's initial ECG clearly qualifies as having "Giant" T waves.

  • To Emphasize — The fact that in addition to Giant T Waves, the ECGs in today's case manifest extreme QTc prolongation narrows the differential diagnosis suggested in Figure-2. That said — marked QTc prolongation may be seen with CNS catastrophes (ie, stroke, bleed, tumor, coma) — as well as with post-tachycardia syndrome. And, extreme QTc prolongation might be attained if a combination of factors was present. BOTTOM Line: The clinical History remains an essential component for interpreting ECGs such as those seen in today's case.

  • The "Good News" — Quick history will rule out post-tachycardia syndrome — an awake and alert patient rules out CNS catastrophe — and bedside Echo as shown above by Dr. Smith in today's case (with non-contractile apical ballooning) allowed rapid confirmation of the diagnosis of Takotsubo Cardiomyopathy in today's case.

Figure-2: List of diagnostic entities to consider when giant T wave inversion is seen.

ECG Findings in Takotsubo Cardiomyopathy:
In the hope of serving as a helpful reminder — I’ve reproduced Figure-3 from My Comment in the March 25, 2020 post of Dr. Smith's Blog — which is the "longer answer" regarding ECG Findings to look for in Takotsubo Cardiomyopathy (adapted from Namgung in Clin Med Insights Cardiol)
  • The initial ECG in today's case (shown above in Figure-1) — illustrates the features of Pattern #2 for Takotsubo Cardiomyopathy (as described below in Figure-3). Specifically — there is diffuse T wave inversion but no ST elevation, in association with marked prolongation of the QTc.

Figure-3: ECG Findings in Takotsubo Cardiomyopathy — adapted from Namgung in Clin Med Insights Cardiol (See text).

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