Background

Myocardial bridge (MB) is known as the predictor for positive coronary artery spasm (CAS). However, there has been no study for the long-term clinical outcome between CAS with and without MB.

Methods

A total of 3,037 patients were enrolled (positive CAS with MB, n=489; positive CAS without MB, n=1297; negative CAS, n=1251).

Results

Baseline clinical characteristics showed more male, older age, and higher incidence of smoking and alcoholic history were found in the positive CAS with MB group. There was no difference in diabetes, hypertension, dyslipidemia, lipid profile, and medication such as beta/RAS/Calcium channel blocker, and statin between two groups. In multivariate binary logistic regression analysis adjusted by co-variates, age, male gender, and myocardial bridge were the predictor for positive CAS. In Cox-regression analysis adjusted by co-variates, positive CAS with MB was not associated with the increased incidence of recurrent chest pain (HR, 1.1; 95% OR, 0.7-1.7). Also, In Kaplan-Meyer curve, there was no statistic significance in incidence of recurrent chest pain requiring coronary angiography during 3-year follow-up period between CAS with MB and CAS without MB, although the incidence of recurrent chest pain was higher in the CAS with MB group.

Conclusions

In our study, we found that positive coronary spasm combined with MB didn't increase the incidence of recurrent chest pain during 3-year follow-up period, compared to positive CAS without MB.

Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.