Kaplan-Meier analyses of composite event-free survival. OPCAB, off-pump coronary artery bypass grafting; ONCAB, on-pump coronary artery bypass grafting. On the X-axis the follow-up in months and on the Y-axis the fraction survival are given. The censored event was defined as death occurring as in-hospital mortality, early and late mortality during follow-up. The censored event was defined as dyspnea according NYHA III, angina pectoris according CCS III, MACCE, recent coronary intervention, in-hospital mortality, early and late mortality occurring during the hospital-stay and follow-up.