Electromechanical Window and Spontaneous Ventricular Tachyarrhythmias in Takotsubo Syndrome

• Published in: The American journal of cardiology Vol. 210; pp. 100 - 106
• Main Authors: Banai, Ariel, Retsky, Rachel, Lupu, Lior, Levi, Erez, Zahler, David, Feder, Omri, Merin, Roei, Topilsky, Yan, Rosso, Raphael, Banai, Shmuel, Viskin, Sami, Chorin, Ehud
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-01-2024; Elsevier Limited
• Subjects: Aged; Aorta; Aortic valve; Cardiac arrhythmia; Cardiomyopathy; Cardiovascular disease; Continuous radiation; Coronary vessels; Echocardiography; Electrocardiography; EMW; Female; Health care facilities; Heart; Heart rate; Heart valves; Hospitals; Humans; Long QT syndrome; Male; Middle Aged; Mortality; Multivariate analysis; Patients; Prolongation; Regression analysis; Retrospective Studies; Stroke Volume - physiology; Tachycardia, Ventricular - etiology; Tachycardia, Ventricular - physiopathology; Takotsubo Cardiomyopathy - complications; Takotsubo Cardiomyopathy - diagnosis; Takotsubo Cardiomyopathy - physiopathology; Takotsubo syndrome; Vein & artery diseases; Ventricle; Ventricular Function, Left - physiology; ventricular tachyarrhythmias; Msec; QAoC; TTS; ventricular tachyarrhythmias; OR; Takotsubo syndrome; CI; ROC; ECG; EMW
• ISSN: 0002-9149; 1879-1913; 1879-1913
• DOI: 10.1016/j.amjcard.2023.10.016

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 evaluate its association to ventricular tachyarrhythmias.
A retrospective analysis of 84 patients hospitalized with TTS in the Tel Aviv Medical Center between 2013 and 2022. All patients underwent a comprehensive echocardiographic evaluation and EMW was calculated by subtracting the QT interval from the QRS-onset to aortic valve closure obtained from a continuous-wave Doppler for the same beat.
Of the 84 TTS patients 74 (88%) were female and mean age was 70 ± 11. Mean left ventricular ejection fraction was 42 ± 8%. EMW was negative in 81 (96%) patients, and mean EMW was -69±50 milliseconds. Ventricular tachyarrhythmias occurred in 7 (8%) patients. EMW of Patients who experienced ventricular tachyarrhythmias was more negative than patients who did not (-133±23 msec vs -63±48 msec; p=0.001). in univariate analysis EMW and QT were associated with ventricular tachyarrhythmias (univariate OREMW: 1.03, 95% CI 1.01-1.05; p=0.003 and univariate ORQTc:1.02, 95% CI 1.01-1.03; p=0.02), however, only EMW remained significant in multivariate analysis (OREMW: 1.03 95% CI 1.03-1.05; p=0.023). EMW was more effective than QTc in identifying patients who had ventricular tachyarrhythmias [AUCEMW: 0.89, (95% CI 0.82-0.97) vs AUCQTc: 0.77 (95% CI 0.61-0.93; p=0.02), and a cutoff value of -108 msec was predictive of ventricular tachyarrhythmias with a sensitivity of 86% and a specificity of 79%.
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 TTS patients warrants further investigation.