Impact of myocardial bridging on in-hospital outcome in patients with takotsubo syndrome.

BACKGROUND: Prevalence of myocardial bridging of the left anterior descending coronary artery (LAD) in patients with takotsubo syndrome (TTS) has been demonstrated. However, the impact of myocardial bridging on in-hospital outcome has not been fully evaluated. METHODS: A total of 144 consecutive patients with TTS were enrolled. Coronary angiography and left ventriculography were performed in all patients and absence of obstructive coronary disease explaining the left ventricular contraction abnormality was confirmed. Myocardial bridging was diagnosed when a dynamic compression in systole, so-called "milking effect", was observed in the LAD. We evaluated differences in the clinical characteristics and in-hospital outcome between patients with and without myocardial bridging. Furthermore, multiple logistic regression analysis was performed to predict in-hospital death. RESULTS: Myocardial bridging was observed in 33 patients (23%). In-hospital death was more frequent in patients with myocardial bridging (21% vs. 6%, p=0.02), which was due mainly to a higher non-cardiac death in those patients (15% vs. 5%, p=0.049). Multiple logistic regression analysis demonstrated myocardial bridging (odds ratio=12.0, 95% CI=2.52-78.5, p<0.01) as one of the independent predictors of in-hospital death. CONCLUSION: Myocardial bridging is an independent predictor of in-hospital death in patients with TTS.