Abstract

Background: Myocardial bridging (MB) is a frequently encountered coronary anomaly, and its prevalence varies, ranging from 1.5% to 16%. The present study evaluates the clinical profile of MB in patients undergoing coronary angiography at a tertiary care center in coastal Karnataka, India. Methodology: This prospective study was performed among patients presenting to the Department of Cardiology and Department of Emergency Medicine from July-2017 to May-2018. All the patients presenting with chest pain, dyspnoea, or fatigue; and planned for coronary angiography (CAG) of age 30 and above who had MB were included in the study. Patient data, including electrocardiogram(ECG), echocardiography(ECHO), and routine blood investigations, were recorded in the pre-designed form. The study was carried out after attaining Institutional ethical clearance. Results: The patient cohort was predominantly composed of males (75.7%) with an average age of 55.2±0.97 years. Among 140 patients with MB, 75.7% of cases were classified as grade I, 20.7% as grade II, and 3.6% as grade III. Significant association was observed between MB grades and clinical factors, such as diastolic dysfunction, active smoking, and diabetes. Electrocardiographic abnormalities included left ventricular hypertrophy (25%), inferior wall myocardial infarction(8%), left bundle branch block (2.9%), and T-wave inversion (2.9%). Echocardiographic findings included concentric LVH (22.9%), regional wall motion abnormality (12.1%), and hypertrophic cardiomyopathy(3.6%). CAG unveiled various pathologies, including mild coronary artery disease(28.6%), single vessel disease(15%), double vessel disease(1.4%), branch vessel disease(5%), and multivessel disease(2.1%). Conclusion: MB was prevalent among patients undergoing CAG. Significant association was found between grades of MB and diastolic dysfunction, active smoking, and diabetes mellitus.

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