Myocardial bridging, systolic compression of an intramyocardial segment of an epicardial coronary artery, is well known to involve native coronary arteries. Systolic compression of bypass grafts has been rarely described. We present two cases of dynamic systolic compression of bypass grafts to native coronary arteries: one of a vein graft to the right coronary artery, and another of a left internal mammary artery to the left anterior descending artery.