Prevalence and Clinical Associations of Myocardial Bridging in Patients Undergoing Coronary Angiography at a Tertiary Care Center in Pakistan

Abstract

Objectives: To determine the prevalence of myocardial bridging and describe its angiographic distribution, demographic profile, and associated clinical characteristics among patients undergoing coronary angiography at a tertiary cardiac center in Pakistan. Methodology: This descriptive cross-sectional study was conducted at the Adult Cardiology Department of the National Institute of Cardiovascular Diseases (NICVD), Karachi, from 16 June to 16 July 2025. A total of 1003 consecutive adult patients (≥18 years) undergoing coronary angiography were enrolled using non-probability consecutive sampling. Patients with prior coronary artery bypass grafting or who declined consent were excluded. Demographic, clinical, and angiographic data were collected using a structured proforma. Myocardial bridging was identified using standard angiographic criteria and confirmed by independent cardiologist review. Multivariable logistic regression was performed to evaluate associations with MB detection. Results: Myocardial bridging was identified in 58 patients (5.78%). The mean age of MB patients was 58 ± 10.3 years, and 82.8% were male. The LAD was involved in 98.3% of cases, predominantly the mid-LAD segment (84.5%). Only 15.5% of MB patients were symptomatic. Atherosclerosis was present in 63.8% of cases, mainly proximal to the bridged segment, with no plaque within the tunneled segment. Age >65 years was associated with higher odds of MB detection, while diabetes mellitus and family history of coronary artery disease were associated with lower odds. Conclusion: Myocardial bridging was observed in approximately 6% of angiography patients, most often involving the mid-LAD and detected incidentally. These findings reflect detection patterns within an angiography-referred population.