Early and long-term outcomes of coronary artery bypass surgery with and without use of heart-lung machine and with special respect to renal function - A retrospective study

The aim of our study was to compare early and long-term outcome of patients undergoing either on-pump or off-pump coronary artery bypass grafting with special focus on impairment of renal function. Five hundred ninety-three consecutive patients undergoing coronary artery bypass grafting were retrospectively analyzed. They were assigned either to on-pump (n = 281) or to off-pump (n = 312) group. Early and long-term outcomes were analyzed with special focus on renal function. Basic demographics and preoperative characteristics did not differ between groups (p>0.05) as well as postoperative renal parameters (p>0.05). Postoperative odds ratios (OR) of off-pump group in comparison to on-pump group were higher without reaching significance in terms of incidence of gastrointestinal complications and pneumonia (OR = 2.23 and 1.61, respectively) as well as hazard ratios (HR) on long-term follow-up for mortality and incidence of myocardial infarction (HR = 1.50 and 2.29, respectively). Kaplan-Meier estimation analysis also revealed similar results for both groups in terms of mid- and long-term survival (Breslow p = 0.062 and Log-Rank p = 0.064, respectively) and for incidence of myocardial infarction (Breslow p = 0.102 and Log-Rank p = 0.103, respectively). Our study suggests that use or not use of coronary artery bypass did not influence postoperative renal function. Odds of early outcomes were similar in both groups as well as incidence of myocardial infarction and mortality in long-term follow-up.