Refractory spasm of coronary arteries and grafted conduits after isolated coronary artery bypass surgery

Refractory vascular spasm (RVS) concomitantly involving the entire coronary artery system and grafted conduits after coronary artery bypass grafting (CABG) surgery is a rare, but dreadful event. No consensus exists in terms of appropriate management.

Between 1986 and 2009, 5,762 patients underwent isolated CABG at our institution, and 7 patients experienced RVS involving the coronary arteries and implanted conduits. Mean age was 65.6 years and 3 were female. All patients received from 3 to 5 distal anastomoses, including use of the left internal mammary artery. During the same time period, 18 patients experienced perioperative vasospasm of a single coronary artery or of a grafted conduit.

All diffuse RVS events occurred between 3 and 8 hours after surgery. All patients had diffuse ischemic-like electrocardiographic changes, and 5 patients rapidly developed cardiogenic shock in the intensive care unit. Angiography was quickly performed in all patients and showed diffuse RVS involving either the native coronary arteries or the anastomosed arterial and venous conduits. The first 5 patients of this series died in the catheterization lab due to rapidly evolving refractory cardiogenic shock and unresponsive cardiac arrest, despite intraaortic counterpulsation and aggressive pharmacologic interventions (selective vasodilators and systemic inotropes). In the last 2 patients, extracorporeal membrane oxygenation was quickly instituted (1 in the catheterization lab, 1 in the operating room) and RVS could be successfully managed with complete resolution of ongoing vasospasm. In the single vascular spasm, there was only 1 death for refractory cardiac arrest, whereas all the other patients were successfully treated with direct infusion of vasodilators.

Diffuse RVS after CABG is a rare but lethal condition. Our experience, although limited, indicates that in such cases an aggressive treatment, that is, prompt extracorporeal membrane oxygenation institution and controlled cardiocirculatory assistance, represents the preferred solution to face such a dramatic event and may save patient lives.