To Örebro University

Background: Takotsubo syndrome (TS) is a potentially life-threatening acute cardiac syndrome with a clinical presentation very similar to myocardial infarction (MI) and for which the natural history, management and outcome remain incompletely understood.

Purpose: The aims of this study were to assess the relative short- and long-term mortality risk of TS , ST-elevation MI (STEMI) and non STEMI (NSTEMI) and to identify predictors of in-hospital complications and poor prognosis in patients with TS.

Methods: Using the nationwide Swedish Angiography and Angioplasty Registry (SCAAR) we identified almost all (n=117,720) patients who underwent coronary angiography due to TS (N=2,898 [2.5%]), STEMI (N=48,493 [41.2%]) or NSTEMI (N=66,329 [56.3%]) in Sweden between January 2009 and February 2018.

Results: Patients with TS were more often women as compared with patients with STEMI or NSTEMI. TS was associated with unadjusted and adjusted 30-day mortality risks lower than STEMI (adjusted hazard ratio [adjHR] 0.60, 95% confidence interval [CI]0.48-0.76, p<0.001), but higher than NSTEMI (adjHR 2.70, 95% CI 2.14-3.41, p<0.001). Compared to STEMI, TS was associated with similar risk of acute heart failure (adjHR 1.26, 95% CI 0.91–1.76, p=0.16) but lower risk of cardio-genic shock (adjHR 0.55, 95% CI 0.34–0.89, p=0.02). The relative 30-day mortality risk for TS versus STEMI and NSTEMI was higher for smokers than non-smokers (adjusted pinteractionSTEMI=0.01 and pinteractionNSTEMI=0.01).

Conclusion: Thirty-day mortality in TS was higher than in NSTEMI but lower than STEMI, despite a similar risk of acute heart failure in TS and STEMI. Among patients with TS, smoking was an independent predictor of mortality