63. Clinical and angiographic profile of myocardial bridges in patients undergoing coronary angiogram for evaluation of chest pain

Abstract

A myocardial bridge is a band of heart muscle that lies on top of a coronary artery, instead of underneath it. First described by pathologists in the early l920’s, myocardial bridges appear almost exclusively in the left anterior descending coronary artery. This occurrence has been recognized for more than 200 years but was first reported in depth by Geiringer in 1951. Systolic compression of the coronary artery by the overlying myocardial “bridge” was first recognized angiographically by Portsmann and Iwig in 1960 to assess both clinical and angiographic profile of myocardial bridge in patients undergoing coronary angiogram for evaluation of chest pain. 4527 patients were evaluated those who were admitted in NICVD, Al-Helal Heart Hospital, Urobangla Heart Hospital, Metropolitan Heart Centre and Lab-Aid Cardiac Hospital, Dhaka between August, 2003 and December, 2010 with diagnostic coronary arteriography. Each cineangiogram was reviewed by at least two qualified cardiologists who evaluated the angiogram and measured coronary lumen diameters were double blinded. Of the 4527 patients studied, 403 (8.9%) had no evidence of angiographically significant coronary artery disease. Thirty nine (39) of these patients were noted to have myocardial bridging, the total incidence of myocardial bridge was 0.87%. Most of the patients (75%) were 30–59 years age group and most of the patients were male (74.35%). 97% patients had history of chest pain and the resting electrocardiogram was normal in 21 patients (53%) whereas 4 patients (10%) had non-specific ST-T wave changes and 6 patients had minor conduction abnormalities. Of the 39 patients with myocardial bridges, 5 (12.8%) had mild systolic coronary compression; 9 (23.95%) had moderate systolic compression and 25 patients (64.25%) had significant compression. Site of myocardial bridges was mostly in mid LAD (51.30%). Other sites were Proximal LAD (25.65%), Distal LAD(12.82%), LCX (05.12%) and RCA (05.12%). The results of the present study would suggest that myocardial bridges are not a benign phenomenon. Only 0.87% of 4527 patients demonstrated myocardial bridges.