Right Ventricular Myocardial Bridge in a Patient with Pulmonary Hypertension

Abstract

Myocardial bridge is a not uncommon finding in routine diagnostic coronary angiography or pathological examination of the heart. It is almost always confined to the left ventricle and the left anterior descending coronary artery. This report describes a patient with chronic lung disease, severe left ventricular dysfunction, and pulmonary hypertension in whom coronary angiography revealed bridging of the right ventricular branch of the right coronary artery.

Multifocal coronary artery myocardial bridging involving the right coronary and left anterior descending arteries detected by ECG-gated 64 slice multidetector CT coronary angiography

“…The incidence of myocardial bridging detected by conventional coronary angiography is much lower than the reported incidences at autopsy (ranging from 5% to 86% percent depending upon the precision of dissection) [2,3,[5][6][7] and at cardiothoracic surgery (reported incidence of 15%) [5]. This disparity has been attributed to multiple factors including the length of the involved segment of the coronary artery and the depth of overlying myocardium with only those coronary artery segments deeply located within the left ventricular myocardium appearing to be sufficiently compressed during systole to be identified by angiography [3].…”

“…Originally described over 200 years ago, myocardial bridging is a congenital variant in which bands of cardiac muscle overlie the otherwise epicardial coronary arteries for variable lengths [1][2][3][4][5][6]. Myocardial bridging was first reported during coronary arteriography in 1960 with Portman and Iwig's description of intermittent coronary artery compression (''milking'') during systole [3].…”

“…Myocardial bridging was first reported during coronary arteriography in 1960 with Portman and Iwig's description of intermittent coronary artery compression (''milking'') during systole [3]. The reported incidence of myocardial bridging seen on coronary angiography ranges from 0.5% to 16%, with the vast majority of cases being confined to the left anterior descending artery, typically in the middle segment [1,2,5,7,8] with higher incidences of myocardial bridging reported in heart transplant patients and those with hypertrophic cardiomyopathy [5,6].…”

“…This disparity has been attributed to multiple factors including the length of the involved segment of the coronary artery and the depth of overlying myocardium with only those coronary artery segments deeply located within the left ventricular myocardium appearing to be sufficiently compressed during systole to be identified by angiography [3]. Right coronary artery myocardial bridging is infrequently identified by coronary arteriography [1,2,[8][9][10][11] and we found only a single case report of isolated right coronary artery bridging identified by CT [12]. In the majority of cases of right coronary artery myocardial bridging, the patients had clinical or radiological evidence of chronic obstructive pulmonary disease with pulmonary hypertension, left ventricular hypertrophy and/or cardiomyopathy [1,2,10].…”

“…Right coronary artery myocardial bridging is infrequently identified by coronary arteriography [1,2,[8][9][10][11] and we found only a single case report of isolated right coronary artery bridging identified by CT [12]. In the majority of cases of right coronary artery myocardial bridging, the patients had clinical or radiological evidence of chronic obstructive pulmonary disease with pulmonary hypertension, left ventricular hypertrophy and/or cardiomyopathy [1,2,10]. These findings contrast to the significantly higher incidences of right coronary artery bridging identified at autopsy by Polacek [13] who demonstrated myocyte overbridging of the right coronary artery and its branches in 41.4% of cases.…”