Off-pump coronary artery bypass grafting

Abstract

Coronary artery bypass grafting (CABG) prior to the discovery of cardiopulmonary bypass (CPB) was performed on a beating heart or “off-pump”. Development of CPB created the optimal conditions of a bloodless and motionless operative field resulting in majority of CABG procedures being performed with the aid of CPB or “on-pump”. However, invasiveness of CPB is a well-established phenomenon and accounts for the morbidity and mortality associated with conventional CABG. Off-pump CABG was rediscovered, more than two decades ago, as a less invasive strategy to abolish or at least reduce the morbidity and mortality associated with CPB. Theoretically off-pump CABG, by avoiding CPB, may improve outcomes by reducing organ dysfunction. In reality several top-quality clinical trials, conducted since the resurgence of off-pump CABG in 1990s, comparing off-pump and on-pump CABG have not been able to substantiate perceived supremacy of beating heart bypass surgery over conventional CABG with respect to key outcomes. At the same time concerns regarding partial revascularization, graft failure and long-term survival have prevented off-pump CABG from widespread adoption. This narrative review gives an insight into the evolution, indications, contraindications, technique, and outcomes of off-pump CABG as well as concerns and controversies associated with it.