Contemporary Review of Myocardial Bridging for Internists.

Myocardial bridging is a congenital coronary condition in which an epicardial coronary artery courses within the myocardial muscle instead of running on its surface. Its prevalence varies depending upon the diagnostic modality used for its testing. It is reported to be 40%-80% in autopsy studies, 58% on coronary artery computed tomography, and 0.5%-16% on invasive coronary angiography. Historically, myocardial bridging was considered to be a benign entity. Recent data have shown that this entity not only can cause chronic angina in patients with non-obstructive coronary artery disease but is also associated with an increased risk of major adverse cardiovascular events. Indeed, this condition remains overlooked and not well understood among internal medicine physicians and even among many cardiologists. This review aimed to describe this disease entity and its clinical presentations, understand the anatomic and physiological mechanisms of angina related to this entity, and introduce a comprehensive algorithm for detailed evaluation and phenotype-guided treatment.