The incidence and significance of myocardial bridge in a prospectively defined population of patients undergoing coronary angiography for chest pain.

Since its first description in 1922, the incidence and pathophysiologic significance of myocardial bridges has remained controversial due to the relatively small size and retrospective design of most studies. We assessed the incidence and clinical consequence of myocardial bridges in 2547 patients undergoing coronary arteriography over a 16-month period at our medical center. Of the 511 patients without fixed coronary obstruction, 26 (5%) were found to have myocardial bridge. Of the 26 patients only 1 demonstrated ischemia as assessed by Tc-99m MIBI myocardial perfusion scintigraphy during treadmill exercise testing in the distribution of the culprit lesion. Therefore, the results of the present study suggest that angiographically detectable myocardial bridges are uncommon in patients undergoing routine angiography and are associated with ischemia in only one patient.