The impact of complete revascularization on long-term survival is strongly dependent on age

Background: Complete revascularization during coronary artery bypass grafting (CABG) has been reported to be associated with better short-term and long-term outcomes. We hypothesized that the survival benefit of complete revascularization would be less in old patients than in young patients.

Methods: We analyzed data from 6,539 consecutive patients who had undergone a first isolated on-pump CABG procedure between 2000 and 2008. We investigated the impact of complete revascularization and its interaction with age on operative and long-term survival using propensity-score-based analyses.

Results: Patients with incomplete (versus complete) revascularization (n=318 [4.9%]) were sicker overall. During a mean follow-up of 5.8±2.2 years, 909 patients died. In the propensity-score-matched analysis, operative mortality was not significantly different between patients with complete revascularization and those with incomplete revascularization (1.9% versus 2.8%; odds ratio [OR], 1.46; 95% confidence interval [CI], 0.56-3.46; p=0.48). In contrast, incomplete revascularization had an independent negative impact on long-term survival, which was strongly age dependent (hazard ratio [HR] for interaction, 0.96 per year increment; p=0.02). In a propensity-score-matched analysis, incomplete revascularization was independently associated with higher long-term mortality in patients younger than 60 years (HR, 3.27; 95% CI, 1.21-8.86; p=0.02), whereas it was not in patients 60 to 70 years and 70 years of age and older (p=0.87 and p=0.24, respectively).

Conclusions: Contrary to what is observed in patients younger than 60 years, complete revascularization does not seem to improve long-term survival in older patients. This suggests that elderly patients at high operative risk may be considered, when deemed clinically appropriate, for limited coronary revascularization.