[Hemodynamic significance of myocardial bridging and milking effect of the anterior interventricular artery: a mild variant or source of angina?].

A hemodynamic study was conducted in 11 patients with myocardial bridging and milking effect (ME) of the left anterior descending artery (LADA), but with otherwise normal coronary arteries. During pacing, patients with grade III ME (over 75% narrowing of arterial size during systole) showed anterior wall ischemia, lactate production and severe angina. Thus, grade III ME observed on coronary arteriography may result in significant obstruction of the LADA with typical angina. Surgical treatment is worth considering in symptomatic patients with this rare anomaly.