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

Background Malignant arrhythmias and circulatory failure after valve surgery are commonly associated with inadequate myocardial protection, electrolyte imbalance, or prosthetic valve dysfunction. In contrast, isolated diffuse coronary vasospasm is rare but potentially fatal. An anomalous right coronary artery (RCA) originating from the left coronary sinus is an uncommon coronary anomaly that may predispose patients to postoperative vasospasm, with limited responsiveness to intracoronary vasodilator therapy. We report such a case to provide a clinical reference. Case presentation 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. Conclusions Diffuse coronary vasospasm after valve surgery may result in refractory circulatory collapse. In patients with anomalous coronary origin, pharmacological treatment may be ineffective, and timely surgical revascularization can be life-saving.