Morphological description and clinical implications of myocardial bridges: an anatomical study in Colombians.

BACKGROUND Myocardial bridges represent a hotly debated research topic. Myocardial bridges are considered to be a vascular heart variation due to its intermittent or enduring reducing of the arterial lumen, with a possible ischemic effect. METHODS 154 hearts were studied, having been extracted as fresh autopsy material. Coronary arteries were injected with synthetic resin and cleaned by extracting the pericardial fat. RESULTS 92 myocardial bridges were observed in 62 hearts (40.3%). Average myocardial bridge length was 19.9 mm. Myocardial bridges varied per artery from one myocardial bridge in 42 hearts (27.3%), two myocardial bridges in 11 hearts (7.2%), three myocardial bridges in 8 hearts (5.2%) and four myocardial bridges in 1 heart (0.7%). Most myocardial bridges coincided with the anterior interventricular artery in its proximal and intermediate segments in 61 cases (39.6%) and left diagonal artery in 11 cases (7.2%). Arteries emitted just before myocardial bridges (pre-bridge branch) in 50 cases (54.3%) of the sample, with an average caliber of 1.41 mm. A third coronary artery was present in 46 cases (29.8%) of total sample. A higher frequency of myocardial bridges was found in hearts with a third coronary artery. CONCLUSION It is necessary to consider the clinical importance of the variations considering the arterial distribution and associated clinical implications.