Long-term results of coronary artery bypass grafting in patients with renal insufficiency

Background There are few published studies on coronary artery bypass grafting in patients with renal insufficiency who are not on maintenance dialysis. No details of long-term results have been published. Methods This retrospective study focuses on 117 consecutive coronary artery bypass grafting patients with renal insufficiency, but who did not require dialysis (group B: preoperative serum creatinine level ≥ 1.5 mg/dL). For comparison purposes, patients on maintenance dialysis (group C: 84 patients) and patients with normal renal function (group A: 794 patients; preoperative serum creatinine level < 1.0 mg/dL) were selected. Results Hospital mortality was 11% (13 of 117) in group B, 5.9% (5 of 84) in group C, and 1.6% (13 of 794) in group A, and between groups A and B, p< 0.0001, and between groups B and C, p = 0.24. Actuarial survival rates at 10 years, including all deaths, were 87%, 32%, and 29% in groups A, B and C, respectively, and between groups A and B, p< 0.009 and between groups B and C, p = 0.63. In 23 patients in group B, the bilateral internal thoracic artery was used. No cardiac deaths were observed in these patients during the mean follow-up time of 42 months (range, 1 to 128 months). Cox model analysis revealed nonuse of arterial grafting (p = 0.03; Hazards ratio 1.7) to be a statistically significant factor, and renal insufficiency (p< 0.0001; Hazards ratio 3.3) and maintenance dialysis (p< 0.0001; Hazards ratio 5.6) to be major independent risk factors for actuarial survival. Conclusions Renal insufficiency was shown to be an independent risk factor for poor prognosis after coronary artery bypass grafting. However, aggressive use of arterial grafts, especially the internal thoracic artery, is recommended to improve late outcomes.