Comparison of clinical profiles between takotsubo syndrome and acute coronary syndrome: a systematic review and meta-analysis.

A systematic review and meta-analysis were performed to analyse the differences in clinical profiles between takotsubo syndrome (TTS) and acute coronary syndrome (ACS) patients and to consolidate the evidence regarding the mortality predictors in TTS patients. Literature search of PubMed, EMBASE and the Cochrane Central Register was made, and 55 studies with a total of 66,653 TTS patients were included. Compared with ACS subjects, TTS subjects had significantly lower left ventricle ejection fraction (LVEF) values on admission; however, cardiovascular risks were fewer and the recovery LVEF was notably higher at both discharge and follow-up in TTS patients than in ACS patients (all P < 0.05). No significant differences were observed either in-hospital mortality or long-term mortality between the two groups (both P > 0.05). Acute renal failure and malignancies were independent predictors of all-cause in-hospital mortality in TTS patients (both P < 0.05). Male sex (HR = 0.565, 95% CI 0.253-0.876, P < 0.001, I = 0.00%), advanced age (HR = 0.054, 95% CI 0.041 to 0.067, P < 0.001, I = 0.00%), shock (HR = 1.382. 95% CI 1.050 to 1.714, P < 0.001, I = 0.00%) and initial LVEF < 35% (HR = 0.962, 95% CI 0.948 to 0.977, P < 0.001, I = 16.8%) were associated with an increased risk of long-time mortality in TTS patients. In conclusion, TTS has significantly different clinical characteristics than ACS. However, the in-hospital and long-term overall mortality rates are not trivial for TTS patients, and some presenting features (underlying diseases, male sex, advanced age, low LVEF and shock) were significantly associated with all-cause mortality.