Angina with non-obstructive coronary arteries and myocardial bridge: long-term outcomes of surgical unroofing.

Abstract

A myocardial bridge (MB) can cause angina in patients with non-obstructive coronary arteries. For patients with a functionally significant MB and severe angina despite maximal medical therapy, surgical unroofing improves short-term symptoms and quality of life (QoL). This study evaluated long-term clinical and symptomatic outcomes of surgical unroofing of a functionally significant left anterior descending artery MB. Two hundred eighteen adult patients who underwent surgical unroofing for an MB were prospectively followed. Preoperative assessments included stress echocardiography, coronary computed tomography angiography, invasive coronary angiography, and intravascular ultrasound. A functionally significant MB was defined as dobutamine-stress diastolic fractional flow reserve (dFFR) and/or resting full-cycle ratio (RFR) ≤ 0.76. The Seattle Angina Questionnaire (SAQ) assessed symptoms and QoL at baseline and follow-up. Additionally, among those with a functionally significant MB, 65 surgically unroofed patients were matched with 65 patients who did not undergo surgery using propensity score matching. The median follow-up was 5 (3-9) years. At follow-up, patients reported significant and highly clinically meaningful improvement in all SAQ domains-physical limitation, anginal stability, anginal frequency, treatment satisfaction, QoL, and SAQ summary score. Unroofed patients reported a significantly greater improvement in physical limitation (27.8 vs 11.4, P = .004) and angina frequency (30 vs 20, P = .01) than the non-surgical patients. Surgical unroofing of a symptomatic and functionally significant MB is associated with significant long-term improvement in symptoms and QoL. For patients with severe angina and failed medical management who have a functionally significant MB, surgical unroofing is a beneficial treatment strategy.