The differential diagnosis of conditions that produce inverted T waves is worth reviewing. It includes more than ischemia and subendocardial infarction!

Differential of T-wave inversion
1° T-wave changes
Normal variants, like juvenile T-wave pattern
CNS events (can be impressive, diffuse, and deep)
Takotsubo cardiomyopathy
Coronary vasospasm
2° T-wave changes
Bundle branch blocks
WPW pre-excitation
Ventricular pacing (memory T-waves)
Acute pulmonary embolism (especially V1-4)

This woman presented with chest pain and shortness of breath after the stressful argument with her daughter. She was taken to the cath lab which revealed clean coronary arteries but left ventricular apical ballooning – Takotsubo cardiomyopathy.

From the differential diagnosis, there are really only four things that can produce such striking, deeply inverted T waves: coronary vasopspasm, subendocardial ischemia, CNS events (stroke or subarachnoid hemorrhage), and Takotsubo cardiomyopathy.

Hayden GE, Brady WJ, Perron AD, et al. Electrocardiographic T-wave inversion: differential diagnosis in the chest pain patient. Am J Emerg Med 20:252, 2002.

Prasad A, Lerman A, Rihad CS. Apical ballooning syndrome (Tako-Tsubo or stress cardiomyopathy): a mimic of acute myocardial infarction. Am Heart J 155:408, 2008.

The rhythm is sinus with an alternating QRS complex morphology – every other QRS is wide with a LBBB morphology. Further evaluation of the wide QRS complex also reveals a short PR interval – this is Wolff-Parkinson-White syndrome with a bypass tract that conducts intermittently. Thus it is a great comparison of a normal AV node conducted complex with the altered complex of Wolff-Parkinson-White (a “fusion” of AV node-His-Purkinje conduction with abnormal ventricular depolarization via a bypass tract).

The trick to this EKG is to recognize WPW as the cause for the wide complex beats – it might be tempting to diagnose bigeminy, or even, intermittent LBBB.

EKG interpretation:
Irregularly irregular narrow complex at 115/minute – ? rhythm
Axis – normal
Intervals – there is a P wave in many R-R spaces, of varying PR
No chamber enlargement, ischemia or infarct patterns

There are two irregularly irregular rhythms – atrial fibrillation and multifocal atrial tachycardia (MAT). MAT is defined as >3 ectopic atrial foci with P waves of differing P wave morphology and differing PR intervals. The R-R intervals are necessarily irregularly irregular. In many of the R-R intervals in this lead II rhythm strip, notice that the T wave is “deformed” by the addition of a P wave.

MAT is often seen in COPD, especially during exacerbation. Other causes are any critical illness, especially with depletion of electrolytes and cations. There is no specific treatment of MAT – first, remedy any underlying process like hypoxia, exacerbation of COPD, fluid status.

And remember this sneaky rhythm when atrial fibrillation with very rapid ventricular rate doesn’t respond to usual treatment for a fib – it may be misdiagnosed multifocal atrial tachycardia (MAT)!