Torsades de Pointes Associated with Takotsubo Cardiomyopathy: Is It Preventable?

Abstract

Takotsubo cardiomyopathy is characterized by transient left ventricular systolic dysfunction and apical dyskinesis (ballooning) in the absence of significant obstructive coronary artery disease. Most patients with Takotsubo cardiomyopathy are females. An emotional stress is believed to be the main trigger of Takotsubo cardiomyopathy (Bybee & Prasad, 2008). Electrocardiographic features of Takotsubo cardiomyopathy might include: ST elevation, T wave inversion, and QT interval prolongation (Thakar et al., 2011). QT interval prolongation might precede Torsades de Pointes a potentially deadly polymorphic ventricular tachycardia. Female gender, left ventricular systolic dysfunction, recent conversion of atrial fibrillation to sinus rhythm, administering QT interval prolonging agents, hypokalemia, hypocalcemia, severe hypomagnesemia, and high-degree atrioventricular block, are all risk factors for acquired QT interval prolongation and Torsades de Pointes (Antzelevitch, 2007; Roden, 2004). The incidence of QT interval prolongation among patient with Takotsubo cardiomyopathy is higher than 50% (Abe et al., 2003; Cangella et al., 2007; Fang et al., 2008; Wittstein et al., 2005), but the incidence Takotsubo cardiomyopathy-associated Torsades de Pointes is probably much lower. It is of great importance to study the clinical circumstances leading to Torsades de Pointes in patients with Takotsubo cardiomyopathy-associated QT interval prolongation since Torsades de Pointes might be fatal, while the prognosis of Takotsubo cardiomyopathy is usually good (Bybee & Prasad, 2008). Takotsubo cardiomyopathy-associated Torsades de Pointes has been reported in 2005 for the first time (Denney et al., 2005). We have reviewed this case report and additional 14 reports (Akashi et al., 2003; Boulouffe et al., 2007; Finsterer et al., 2007; Furushima et al., 2008; Ghosh et al., 2009; Hirose et al., 2008; Inoue et al., 2009; Kurisu et al., 2008; Mahida et al., 2009; Nault et al., 2007; Okada et al., 2007; Patel et al., 2007; Sasaki et al., 2006) concerning Takotsubo cardiomyopathy-associated Torsades de Pointes in 2009, and we have concluded that males with Takotsubo cardiomyopathy-associated QT interval prolongation are at risk for Takotsubo cardiomyopathy-associated Torsades de Pointes although most patients with Takotsubo cardiomyopathy are females. There has been a trend in the mean maximal QT interval being longer among patients with Takotsubo