Ventricular Fibrillation Arrest Due to Coronary Endothelial Dysfunction-Vasospasm After Myocardial Bridge Unroofing:...

Myocardial bridge (MB) can be associated with chest pain when hemodynamically significant. Surgical unroofing of hemodynamically significant MB is indicated when refractory to maximal or maximally tolerated medical therapy. Concomitant endothelial dysfunction within MB increases risk of life-threatening spasm-induced ventricular arrhythmias perioperatively.

A 56-year-old woman with hemodynamically significant mid-left anterior descending artery MB, concomitant endothelial dysfunction within and outside the bridged segment on coronary reactivity testing, and chest pain refractory to medical therapy, presented for surgical unroofing of MB. Ventricular fibrillation cardiac arrest developed postoperatively secondary to culprit severe diffuse coronary vasospasm involving all 3 coronary arteries.

Successful surgical unroofing of bridging is recommended in hemodynamically significant MB patients who fail maximally tolerated calcium-channel blockers or beta-blockers. With concomitant endothelial dysfunction, patients are at increased risk of ventricular arrythmias secondary to severe coronary vasospasm. This can be mitigated with perioperative nondihydropyridine calcium-channel blockers or long-acting intravenous nitrates.

Perioperative intravenous diltiazem/verapamil or nitroglycerin drips when undergoing surgical unroofing should be considered to mitigate the risk of spasm-induced ventricular fibrillation arrest concomitant to endothelial dysfunction within or outside the bridged segment.