Abstract 17302: Apico-Basal Gradient of Left Ventricular Myocardial Edema Underlies Transient T-Wave Inversion and QT Interval Prolongation (Wellens' ECG Pattern) In Tako-tsubo Cardiomyopathy

Abstract

Background: Tako-Tsubo Cardiomyopathy (TTC) is a heart muscle disease presenting with chest pain, ST-segment elevation followed by T-waves inversion and QT interval prolongation (Wellens’ ECG pattern) and left ventricular (LV) dysfunction, which may mimic an acute coronary syndrome. This study was designed to investigate the pathophysiologic basis of the Wellens’ ECG pattern in TTC by characterization of underlying myocardial changes using cardiac magnetic resonance (CMR).

Methods and Results: The study population included 20 consecutive patients with TTC (95% females, mean age 65.3 ± 10.4 years) who underwent CMR studies both in the acute phase and after 3-months of follow-up, using a protocol which included cine images, T2-weighted sequences for myocardial edema and post-contrast T1-weighted inversion recovery sequences for late gadolinium enhancement (LGE). Quantitative ECG indexes of repolarization, such as maximal amplitude of negative T-waves (NTWm), sum of the amplitudes of negative T waves (NTWs) and maximum QT interval (QTc max), were correlated to CMR findings. At the time of first CMR study, there was a significant linear correlation between apico-basal ratio of T2 signal intensity (SI) and NTWm (ρ=0.498; p=0.02), NTWs (ρ=0.483; p=0.03) and QTc max (ρ=0.520;p=0.02). ECG repolarization indexes were unrelated to either LGE on post-contrast sequences or quantitative cine parameters. Wellens’ ECG abnormalities and myocardial edema showed a parallel time course of development and resolution on acute and follow-up CMR studies.

Conclusion: Our study results show that the ischemic-like Wellens’ ECG pattern in TTC coincide and quantitatively correlate with the apico-basal gradient of myocardial edema as evidenced by CMR. Dynamic negative T-waves and QTc prolongation are likely to reflect the edema-induced transient inhomogeneity and dispersion of repolarization between apical and basal LV regions.