Electromechanical Window and Spontaneous Ventricular Tachyarrhythmias in Takotsubo Syndrome

QT interval prolongation is common in patients hospitalized with Takotsubo syndrome (TTS), however, only a minority experience ventricular tachyarrhythmias. Our aim was to characterize the electromechanical window (EMW) in patients with TTS and to evalu-ate its association with ventricular tachyarrhythmias. We preformed aretrospective analy-sis of 84 patients hospitalized with TTS in the Tel-Aviv Medical Center between 2013 and 2022. All patients underwent a comprehensive echocardiographic evaluation and the EMW was calculated by subtracting the QT interval from the QRS onset to the aortic valve closure obtained from a continuous-wave Doppler for the same beat. Of the 84 patients with TTS, 74 (88%) were female and the mean age was 70 +/- 11 years. The mean left ventricular ejection fraction was 42 +/- 8%. The EMW was negative in 81 patients (96%), and the mean EMW was -69 +/- 50 ms. Ventricular tachyarrhythmias occurred in 7 patients (8%). The EMW of patients who experienced ventricular tachyarrhythmias was more negative than patients who did not (-133 +/- 23 ms vs -63 +/- 48 ms, p = 0.001). In the univariate analysis, EMW and QT were associated with ventricular tachyarrhyth-mias (univariate odds ratio [OR]EMW 1.03, 95% confidence interval [CI] 1.01 to 1.05, p = 0.003 and univariate ORQTc 1.02, 95% CI 1.01 to 1.03, p = 0.02); however, only EMW remained significant in the multivariate analysis (OREMW 1.03 95% CI 1.03 to 1.05, p = 0.023). EMW was more effective than corrected QT interval in identifying patients who had ventricular tachyarrhythmias (AUCEMW: 0.89, 95% CI 0.82 to 0.97 vs AUCQTc0.77, 95% CI 0.61 to 0.93, p = 0.02), and a cut-off value of -108 ms was predictive of ventricular tachyarrhythmias with a sensitivity of 86% and a specificity of 79%. In conclusion, EMW is negative in patients with TTS and is associated with increased risk for ventricular tachyarrhythmias. The role of EMW in the risk stratification of patients with TTS war-rants further investigation. (c) 2023 Elsevier Inc. All rights reserved. (Am J Cardiol 2024;210:100-106)

Automated summary

This study aims to evaluate the association between electromechanical window (EMW) and ventricular tachyarrhythmias in patients with Takotsubo syndrome (TTS). The study found that TTS patients had a lower EMW value, which was associated with an increased risk of ventricular tachyarrhythmias.