P6393Serial ECG characteristics in Tako-tsubo cardiomyopathy: comparison with myocardial infarction

Abstract

Introduction: Tako-tsubo cardiomyopathy (TTC) is an acute form of left ventricular systolic impairment that mimics acute myocardial infarction (MI) in its presentation. Here we explore if any differences in ECG morphology/time-course may add confidence in separating the two conditions. Methods: We examined serial ECG's of 21 consecutive acute TTC patients (66±9 years, 19 F) & 21 MI patients (58±9 years, 6F), all with anterior ST elevation. We analysed the following parameters from day 0 to day 3: Number of abnormal leads, Magnitude of ST elevation in each lead and sum of the ST elevation in all leads, T wave amplitude in each lead and sum of the T wave amplitude in all leads, mean 12-lead QT and QTc intervals. Results: All ECG's were in sinus rhythm. The presenting ECG (day 0) showed: 1) significantly fewer abnormal leads in the TTC vs MI group (7±0.5 vs 8.6±0.5, p=0.04) but similar number of leads with ST elevation; 2) significantly lower mean magnitude of ST elevation in the TTC vs MI group (0.91±0.19 mm vs 1.71±0.19mm, p<0.006); and 3) significantly lower sum of T wave amplitude in the TTC vs MI group (16.4±13 vs 25.7±14 p=0.028) -this remained significant on day 1 (0.29±15 mm vs 18.8±8 mm, p<0.001 and day 2 (-11.82±12.4mm vs 9.3±12.4mm, p=0.018) and showed a similar trend in day 3 (-28.18±29.0 mm vs 6.5±16.1 mm, p=0.06) -See Figure The was no significant difference in the QTc between the 2 groups on the day of presentation however on day 1 the QTc was significantly longer in the TTC group (457.7±10.3ms vs 416±10.7ms, p=0.006). The change in QTc between Day 0 and day 3 was significantly greater in the TTC group when compared to the MI group (48.02±9.75 vs 28.5±11.2, p=0.000).T wave amplitude in TTC vs MI day 0-3 Conclusion:The differences in presenting (day 0) ECG between TTC and MI are significant but subtle. We describe further differences in the post-acute phase with significantly greater T wave amplitude changes in TTC compared with MI developing in days 1-3 and a QTc interval that increases significantly in TTC vs MI between days 0-3. These findings firstly aid in the diagnostic confidence of those patients with non-obstructive coronary arteries and secondly, may provide further insight into the distinctive pathophysiology of the two conditions.

An Update on Cardiac Magnetic Resonance Imaging in Takotsubo Cardiomyopathy

“…It is the practice of the authors' institution that patients with troponin positive chest pain and absence of a clear culprit lesion on coronary angiogram are further risk stratified based on left ventriculogram and echocardiogram and specifically those with atypical ballooning patterns are fast tracked to early CMR. ECG changes in the post-acute phase with significantly greater T wave amplitude which is also widespread in a 12lead ECG 24-48 h after presentation, accompanied by increases in QTc interval which is also a valuable tool in differentiating Takotsubo from MI [16]. ST depression in aVR and absence of ST elevation in V1 has been shown to suggest Takotsubo with sensitivity and specificity of > 90% [17].…”