Myocardial bridging of coronary arteries associated with an impending acute myocardial infarction

Abstract

Summary: A 57-year-old woman developed severe substernal chest pain rddiating to the left arm accompanied hy pallor and marked diaphoresis. These symptoms appeared at rest, lasted 45 minutes, and terminated spntaneously. The patient had been treated for mild hypertension during the last 6 months. An ECG tracing obtained at the beginning of treatment was unremarkable. However, an ECG tracing recorded shortly after the end of the symptoms showed T-wave inversion in all anterior leads. Coronary arteriography was then performed and showed no fixed obstructive coronary artery disease. Nonetheless, a lengthened and constricted myocardial bridging of both the left anterior descending coronary artery and its major diagonal branch was detected. Also, he left anterior descending coronary artery was observed very short. terminating before the cardiac apex. The kft ventricle was hypertrophied. The patient was treated with a beta-blocking agent which eliminated all symptoms.ECG tracing obtained about three months after the onset of the clinical picture was nornial. Our findings suggest that marked myocardial ischemia at rest does occur in patients having myocardial bridges under special circumstances, such as lengthened and constricted myocardial bridging of a short coronary artery which supplies a hypertrophied ventricle. This anomaly should be taken into account as a possible cause of a threatened myocardial infarction, which may be successfully treated with a beta-blocking agent.

Myocardial bridging increases the risk of coronary spasm

“…Some case reports have indicated that a relationship exists between MB and major cardiac events, such as myocardial infarction [12][13][14][15][16][17] and cardiac sudden death. [18][19][20][21] Several factors may account for MB-related myocardial ischemia.…”

“…[1][2][3] The frequency of MB has been reported to range from 5.4 to 85% in autopsy series [4][5][6] and from 0.5 to 29.4% on coronary angiography. 1,[6][7][8][9][10][11] Although it remains to be determined how MB affects the cardiovascular system, MB has been associated with myocardial infarction [12][13][14][15][16][17] and sudden cardiac death, [18][19][20][21] and coronary spasm is thought to be one factor connecting cardiac events and MB. 13,22,23 However, it has yet to be verified that coronary spasm is more frequent in patients with MB.…”

Evaluation of Myocardial Bridge With Multidetector Computed Tomography

“…13,18,20 However, it has been reported that MB may be responsible for flow disturbances, myocar dial ischemia and infarction, arrhythmia and sudden death. 1,2,[4][5][6][7][8]13 In our study, 3 patients were thought to have ischemiarelated MB. MB is also a problem during bypass surgery.…”

“…15 The location of the MB in our study was most commonly in the midLAD, in concordance with previous reports. 6,8 Generally, the incidence of MB is between 0.5% and 2.5% angiographically and between 15% and 85% pathologically. 1,2 In our study, the incidence of MB (6.42%) was higher than reported in an angiographic series, but similar to that reported in some 16slice MDCT series.…”

Prevalence and three-year follow-up of patients with isolated myocardial bridge in the mid-Black Sea region: a retrospective single-center study

“…Nevertheless, connections with unstable angina, acute myocardial infarction, arrhythmia, and sudden death have been reported. [18][19][20][21] In the treatment of MB, beta-blockers and nondihydropyridine calcium-channel blockers should be considered first, due to their negative inotropic and chronotropic effects. [22] Nitrates used in coronary artery stenosis should be avoided due to their effects on systolic contraction rate and attendant worsening of symptoms.…”