Clinical and Angiographic Characteristics of Myocardial Bridges: a Descriptive Report of 19 Cases and Follow-up Outcomes

Abstract

Background: Muscle fibers overlying the intramyocardial segment of an epicardial coronary artery are termed myocardial bridge (MB). The aim of this study was to analyze the mid-term outcome of MB and to examine its possible association with angiographic findings and concomitant cardiac pathologies such as hypertrophic cardiomyopathy (HCM).  

Methods: From a total of 3218 patients admitted for coronary angiography during 9 consecutive months, 28 (0.9%) were diagnosed with MBs with stenoses >=50%. Of these, 19 referred for follow-up with a median duration of 18 months.

Results: HCM was present in 5 patients (26.3%), of whom 4 had MB as the sole finding in angiography.  Of the 19 patients, 14 had diastolic dysfunction. In follow-up, 2 patients were treated with revascularization strategies due to the concomitant coronary artery disease and in 2, syncope occurred. For two patients, an intra-cardiac device and a permanent pacemaker were implanted. Three patients with MB as the sole finding in angiography were readmitted because of chest pain.

Conclusion: Diastolic dysfunction may contribute to the presentation of symptoms of muscle bridging. Also, myocardial bridging as the only finding in coronary angiography is highly associated with hypertrophic cardiomyopathy and may help to detect this group of patients. The mid-term outcome of myocardial bridges is favorable.