Long-term excess mortality in takotsubo cardiomyopathy: predictors, causes and clinical consequences

Despite increasing research efforts, the prognostic consequences of takotsubo cardiomyopathy (TTC) remain largely unknown. The aim of this study was therefore to compare the long-term mortality rate of TTC patients with high-risk patients presenting with ST-segment elevation myocardial infarction (STEMI).

A total of 286 patients with TTC were matched for age and gender with 286 STEMI patients. Outcome was obtained with a standardized telephone follow-up. The primary analysis determined long-term mortality. A secondary analysis was performed evaluating 28-day and 1-year mortality. Follow-up was available for 96% of patients after a mean of 3.8 ± 2.5 years. In TTC patients, long-term mortality was significantly higher compared with the matched STEMI cohort [24.7% vs. 15.1%, hazard ratio (HR) 1.58, 95% confidence interval (CI) 1.07-2.33; P = 0.02]. There was no significant difference in the rates of 28-day (5.5% vs. 5.7%, HR 0.96, 95% CI 0.47-1.94; P = 0.91) and 1-year mortality (12.5% vs. 9%, HR 1.42, 95% CI 0.85-2.38; P = 0.18). In multivariable regression analysis, male sex, a high Killip class on admission, and diabetes mellitus were identified as independent predictors of mortality in TTC patients. A risk score consisting of these factors showed a higher mortality with an increasing number of risk factors.

Mortality rates in TTC patients are higher than previously expected and long-term mortality exceeded that of patients with STEMI. A simple risk score may provide an approach to identify high-risk patients and predict clinical prognosis.