OBJECTIVES: Coronary artery bypass grafting (CABG), one of the treatment approaches for coronary artery disease, can be conducted with (on-pump) or without (off-pump) the use of a heart-lung machine. The long-term benefits of off-pump versus on-pump (traditional) CABG are debatable. This study compared on-pump and off-pump 5-year event-free survival from major cardiac and cerebrovascular events (MACCE) and quality of life of patients who underwent on-pump versus off-pump CABG surgery. METHODS: This retrospective cohort study included all patients who underwent CABG at Nork Marash Medical Center (NMMC), Armenia from 2009 to 2010. Data were collected from patient telephone surveys (March 2015), the NMMC electronic surgical database, and medical records. RESULTS: Among 528 patients, 407 (77.1%) underwent on-pump and 121 (22.9%) off-pump CABG. The groups differed at baseline by age, gender, prevalence of hypertension, cerebrovascular disease, gastrointestinal disease, and diabetes. The average EuroSCORE was significantly higher in the off-pump group, indicating a higher surgical risk. The mean follow-up time was 58.2 months for the on-pump and 59.5 months for the off-pump groups. Overall patient health status, estimated via the EQ-5D visual analogue scale, showed no significant differences. After controlling for EuroSCORE and diabetes, the hazard of developing MACCE was similar (HR=0.96 for on-pump versus off-pump, 95% CI: 0.56-1.65). CONCLUSIONS: At 5-year follow-up, no significant differences were observed in the risk of developing major cardiac and cerebrovascular events or quality of life between the off-pump and on-pump CABG patients. Further research is needed to define the patient populations that will benefit the most from each type of surgery.