Echocardiographic correlates of major adverse cardiac events at 1 year in patients with apical ballooning takotsubo syndrome

Abstract

Introduction: Takotsubo syndrome (TTS) is characterized by transient left ventricular dysfunction and associated with considerable morbidity and mortality. We sought to evaluate the association between change in cardiac mechanics after diagnosis of TTS with 1-year incidence of major adverse cardiovascular events (MACE).

Methods: We retrospectively identified 85 patients with apical TTS based on ICD 9/10 codes and chart adjudication, who had a follow-up echocardiogram within 6 months of diagnosis. Echocardiograms were analyzed for left ventricular ejection fraction (LVEF), global longitudinal strain (GLS), GLS ratio, global circumferential strain (GCS), and global radial strain (GRS). Multivariable logistic regression was performed to identify parameters associated with MACE (all-cause mortality, heart failure, stroke, and coronary artery disease [CAD] requiring percutaneous coronary intervention [PCI]) at 1 year. Event-free survival was assessed in patients with GLS (≤-18% vs. >18%) and LVEF (≥53% vs. <53%).

Results: Within 1 year of diagnosis, MACE occurred in 15 (18%) patients. Between baseline and follow-up echocardiogram (median 15 [range 1-151] days), there were significant differences in change in LVEF and GLS in patients with versus without incident MACE. In multivariate analysis, change in LVEF (odds ratio [OR] = .93 [.87, .98], p = .013) and change in GLS (OR = 1.32 [1.04, 1.67], p = .022) were independently associated with MACE; however, the association with change in GLS was attenuated (odds ratio [OR] = 1.13 [.94, 1.36], p = .21) after adjustment for baseline and change in LVEF. Among patients with normalized LVEF at follow-up, there were five (14.7%) MACE; whereas, there were no events among patients with normalized GLS.

Conclusions: In patients with apical TTS, recovery in GLS and LVEF at follow-up was associated with significantly lower MACE at 1 year. Normalization of GLS at follow-up was better able to discriminate event-free survival than normalization of LVEF.

Keywords: major adverse cardiac events; strain; takotsubo.