Myocardial bridges: effect of propranolol on systolic compression.

Myocardial bridges may exert an ischemic effect on the myocardium and often warrant therapy including surgical correction in selected cases. Decrease in systolic compression after the administration of propranolol has not been reported. We report a patient who demonstrated angiographic systolic compression of the coronary artery with subsequent improvement on treatment with propranolol. The reduction in severity of systolic compression caused by propranolol may be due to the negative inotropic effect and perhaps from an increase in coronary artery vascular tone secondary to a beta-blocker with unopposed alpha effect. Further studies are needed to assess the efficacy of beta-blocker therapy in patients with myocardial bridging and the use of intravenous propranolol at the time of coronary angiography may have practical implications in selecting drug therapy for patients with symptomatic myocardial bridging.