Diffuse coronary vasospasm causing refractory ventricular fibrillation after minimally invasive mitral valve replacement in a patient with anomalous right coronary artery: a case report

Malignant arrhythmias and circulatory failure after heart valve surgery are most commonly associated with inadequate myocardial protection, electrolyte disturbances, and prosthetic valve dysfunction. In contrast, isolated diffuse coronary vasospasm is a rare peri-operative complication with substantial risk of life-threatening cardiogenic shock and high early mortality when unrecognized. Anomalous origin of the right coronary artery (RCA) arising from the left coronary sinus represents a rare congenital coronary anatomical variant, which may confer increased susceptibility to peri-operative vasospasm under surgical physiological stress. Furthermore, this abnormal ostial location frequently results in technical difficulty for selective guide-catheter engagement during emergency coronary angiography, limiting local intracoronary vasodilator delivery and rendering pharmacologic management particularly challenging in acute postoperative scenarios. Herein, we report a case of diffuse coronary vasospasm following rheumatic valve surgery in a patient with an anomalous right coronary artery originating from the left coronary sinus, and summarize our diagnostic and therapeutic experience to provide a reference for similar clinical scenarios. A 58-year-old man with a 10-year history of rheumatic heart disease and hypertension was admitted with cough, sputum production, palpitations, and orthopnea. The preoperative diagnoses included rheumatic mitral stenosis, persistent atrial fibrillation, left atrial thrombus, tricuspid regurgitation, and an anomalous RCA arising from the left coronary sinus without significant stenosis. The patient underwent minimally invasive mitral valve replacement along with concomitant procedures. After aortic declamping, he developed ventricular arrhythmias, global myocardial hypokinesia, and failed to wean from cardiopulmonary bypass, requiring venoarterial extracorporeal membrane oxygenation (VA-ECMO) support. In the intensive care unit (ICU), recurrent ventricular arrhythmias accompanied by ST-segment elevation were observed. Emergency coronary angiography demonstrated diffuse coronary vasospasm. The spasm in the left coronary system resolved after administration of vasodilators, whereas the anomalous RCA showed a poor response to intracoronary drug therapy. Emergency coronary artery bypass grafting was subsequently performed. The patient recovered uneventfully and was discharged with normal cardiac function. Diffuse coronary vasospasm represents a rare but life-threatening complication following cardiac valve surgery and may lead to refractory circulatory collapse. When this complication occurs in patients with congenital anomalous coronary anatomy, pharmacological therapy is prone to failure due to challenges in targeted intracoronary drug delivery. Timely surgical revascularization should therefore be considered early and may prove life-saving for these high-risk individuals.