Randomized trial comparing off-pump to on-pump coronary artery bypass grafting in high-risk patients

The subset of patients most likely to benefit from off-pump coronary artery bypass grafting (CABG) remains a controversial issue, but the technique has been proposed to decrease postoperative mortality and morbidity. Th e objective of this study was to compare off-pump to onpump CABG in patients with known risk factors for mortality and morbidity.

Between October 2001 and September 2002, 65 high-risk patients were prospectively randomized to undergo off-pump or o n-pump CABG. Recruited patients had at least 3 of the following criteria: age greater than 65 years, high blood pressure, diabetes, serum creatinine greater than 133 mol/L, left ventricular ejection fraction lower than 45%, chronic pulmonary diseas e, unstable angina, congestive heart failure, repeat CABG, anemia, and carotid atherosclerosis. Hospital mortality and morbidity were the primary end-points of the study.

Six patients (9%) crossed over from the original randomized group. Twenty-eight patients averaging 70 +/- 8 years of age underwent 3 +/- 1 grafts off pump, and 37 patients averaging 70 +/- 6 years of age underwent 3.4 +/- 1 grafts on pump. Revascularization was considered complete in 21 (7 5 %) of off-pump patients compared to 33 (89%) of onpump patients (P =.1). There were no hospital deaths in off-pump patients, and 2 patients (5%) undergoing onpump CABG died early following surgery (P =.2). Two offpump (7%) compared to 11 on-pump (30%) of patients presented composite end-points including death, neurological injury, renal failure, respiratory failure, and operative myocardial infarction after CABG (P =.02).

The present study suggests that off-pump CABG, when technically feasible, significantly reduces morbidity following surgery in a group of high-risk patients.