Off-pump versus on-pump coronary artery bypass grafting surgery in high-risk patients: PRAGUE-6 trial at 30 days and 1 year

Aims: Off-pump coronary artery bypass graft surgery (OPCAB) is an established alternative to on-pump surgical revascularization. Previous studies in patients with low or intermediate risk showed no significant differences between off-pump and on-pump surgical revascularization. The aim of this study was to compare the two techniques in patients with high operative risk. Methods: PRAGUE-6 is a prospective randomized single-center study of 206 patients, with an additive EuroSCORE ≥ 6, scheduled for isolated coronary surgery: Group A - on-pump (n = 108) versus Group B - off-pump (n = 98). The primary outcome was a combined endpoint of all-cause deaths, stroke, myocardial infarction, or renal failure requiring new hemodialysis, within 30 days and 1 year after randomization. All data were analyzed using the "intention-to-treat" principle. Results: Early postoperative myocardial infarction was detected in 12.1% (A) vs. 4.1% (B) of patients (P = 0.048, hazard ratio 0.32, 95% CI 0.11-0.99). There was a significantly higher incidence of primary combined end-point in group A (20.6% vs. 9.2%, P = 0.028, HR 0.41, 95% CI 0.19-0.91) in the first 30 days, but not after 1 year (30.8% vs. 21.4%, P = 0.117, HR 0.65, CI 0.37-1.12). Conclusion: Off-pump surgical revascularization in patients with high operative risks can significantly reduce the incidence of major postoperative complications during the first 30 days. There was no statistically significant difference in the incidence of these complications after 1 year.