Prognostic relevance of GRACE risk score in Takotsubo syndrome

Background: Takotsubo syndrome is an increasingly recognised cardiac condition that clinically mimics an acute coronary syndrome, but data regarding its prognosis remain controversial. It is currently unknown whether acute coronary syndrome risk scores could effectively be applied to Takotsubo syndrome patients. This study aims to assess whether the Global Registry of Acute Coronary Events (GRACE) score can predict clinical outcome in Takotsubo syndrome and to compare the prognosis with matched acute coronary syndrome patients. Methods: A total of 561 Takotsubo syndrome patients was included in this prospective registry. According to the GRACE score, the population was divided into quartiles. The primary endpoint was all-cause mortality and the secondary endpoints were cardiocerebrovascular events (a composite of all-cause mortality, cardiovascular death, recurrence of Takotsubo syndrome and stroke). Results: The median GRACE risk score was 139 +/- 27. Takotsubo syndrome patients with a higher GRACE risk score mostly have a higher rate of physical triggers and lower left ventricular ejection fraction on admission. During long-term follow-up, all-cause mortality rates were 5%, 11%, 12% and 22%, respectively, in the first, second, third and fourth quartile (P<0.001). After multivariate analysis, the GRACE risk score was found to be a strong predictor of all-cause mortality (odds ratio (OR) 1.68, 95% confidence interval (CI) 1.28-2.20; P=0.001) and cardiocerebrovascular events (OR 1.63, 95% CI 1.26-2.11; P=0.001). Moreover, all-cause mortality in Takotsubo syndrome patients was comparable with the matched acute coronary syndrome cohort. Conclusion: In Takotsubo syndrome, the GRACE risk score allows us to predict all-cause mortality and cardiocerebrovascular events at long-term follow-up.