Influence of innovative techniques on midterm results in patients with minimally invasive direct coronary artery bypass and off-pump coronary artery bypass

Background: There is a paucity of midterm results comparing the efficacy of minimally invasive direct coronary artery bypass (MIDCAB) and off-pump coronary artery bypass (OPCAB) with standard coronary artery bypass grafting (CABG). In addition, the advent of innovative techniques may have improved midterm results for patients who undergo MIDCAB and OPCAB (MID-OPCAB). The purpose of this study was to evaluate the midterm survival results of higher-risk patient groups who have undergone CABG or MID-OPCAB with or without the use of innovative techniques. Methods: From January 1992 through March 2002, 3670 consecutive patients underwent coronary artery bypass procedures, and their predicted surgical risks were calculated according to the logistic EuroSCORE. The cases of 52 MIDCAB patients and 1796 CABG patients with similar higher-risk EuroSCOREs (11.5 versus 11.4, respectively) who underwent operations from January 1992 to December 1997 were compared (study A). The cases of 89 patients with MID-OPCAB (employing "innovative techniques") and 796 patients with CABG (EuroSCORE, 13.2 versus 13.3, respectively) whose operations took place between 1998 and 2002 were also compared (study B). The National Death Index was used to access mortality data, and Kaplan-Meier curves were constructed for each group of patients. Numbers of arterial grafts, numbers of anastomoses, major complications, in-hospital lengths of stay (LOS), and 30-day mortality rates were noted. Results: In study A, there were no significant differences in the 30-day mortality rates (2.5% versus 3.9%), incidences of major complications (11.5% versus 16.6%), and LOS (13 days versus 11.7 days) for the MID-OPCAB and CABG patients, respectively. CABG patients received more arterial grafts (47.1% versus 28.9%; P = .011), received more distal anastomoses (3.4 versus 2.7; P < .001), and had better survival as estimated by Kaplan-Meier curves (94.5 months versus 82.1 months; P = .023). In study B, there were no differences in 30-day mortality rates (3.1% versus 2.3%) and incidences of major complications (10.1% versus 12.7%) for MID-OPCAB and CABG patients, respectively. CABG patients received more arterial grafts (72% versus 57.3%; P = .004) and more distal anastomoses (3.5 versus 2.8; P < .001). However, LOS was shorter for MID-OPCAB patients (7.2 days versus 9.6 days; P = .019), and there was no difference in survival time as estimated by Kaplan-Meier curves (47 months versus 46.4 months; P = .534). Conclusions: The advent of innovative surgery significantly improved LOS and "equalized" the rate of survival to 5 years in higher-risk MID-OPCAB patients, compared with similar-risk CABG patients.