Myocardial Bridging

A patient reports pressure in the chest whenever a run or emotional argument makes the heart race. The coronary angiogram shows no fixed obstructive lesion, yet the symptoms and stress test are convincingly ischemic. Myocardial bridging is one explanation that should remain in the differential. A myocardial bridge is a congenital anatomical variant in which a segment of an epicardial coronary artery travels through the myocardium instead of lying entirely on its surface. The mid left anterior descending artery is the usual location. The artery is not narrowed by plaque; it is compressed dynamically by the band of muscle over it. Many bridges are incidental, but a functionally significant bridge can produce angina, acute coronary syndrome, ventricular arrhythmia, or rarely sudden cardiac death. The bedside pattern is therefore more useful than the label alone: symptoms linked to exertion, emotional stress, catecholamine excess, or another tachycardic state deserve assessment even when the coronary arteries appear non-obstructive.