Introduction:

The myocardial bridging (MB) is a rare clinical entity, with a prevalence of 0.15-16% in angiographic series and 5-86% in autopsy series; considered of benign course; commonly associated with hypertrophic cardiomyopathy and infrequently with acute coronary syndromes (ACS).

Justification:

Report this rare association of pathologies, with few reports in the literature.

Clinical case:

61-years-old male, without previous chronic degenerative diseases, current smoker. He started 4 hours prior to admission with sudden anginal chest pain, dyspnea, and profuse diaphoresis. Electrocardiogram: left bundle branch block, sinus rhythm with HR 44 bpm. Troponin I: 0.6 µg/L. A diagnosis of STEMI with cardiogenic shock was integrated. Emergency coronary angiography was performed reporting epicardial arteries without obstructive lesions, with the presence of muscle bridges in the left anterior descending artery in the middle and distal segments, in the first diagonal and the vertical segment of the right coronary artery with severe milking phenomenon. Ventriculogram: with mild anteroapical hypokinesia and asymmetric septal hypertrophy of the left ventricle without intraventricular gradient or Brockenbrough-Braunwald phenomenon. No clinical improvement despite specific treatment management, so a successful supra-arterial decompression myotomy was performed. Vasoactive amines were withdrawn, with an adequate postoperative clinical course, so he was discharged home asymptomatic. Control echocardiogram without alterations of ventricular mobility, remaining asymptomatic at six months of follow-up.

Conclusions:

Although infrequent as in our case, the association of hypetrophic cardiomyopathy and MB may occur with ACS. This association has not been ruled out as a possible cause of ischemia and sudden death in these patients. The literature supports the use of beta-blockers and supra-arterial myotomy or coronary bypass as surgical treatment. Percutaneous treatment is not recommended. There is no consensus for its management, and treatment must be individualized in each patient.