Waiting time and mortality after elective coronary artery bypass grafting

Limited resources for coronary artery bypass grafting (CABG) results in waiting times, prioritization between patients, and to mortality among the patients on the waiting list. Waiting time is an independent predictor for mortality on the waiting list, but it is not clear if the waiting time also influences outcome after CABG.

The study population was 5453 consecutive CABG patients who were prioritized at acceptance into three groups: imperative (CABG intended within 2 weeks), urgent (within 12 weeks), and routine (within 6 months). Postoperative mortality was compared between patients operated on within or after the intended waiting time in their respective groups. A multivariate Poisson regression model was used to further determine the effect of waiting time on postoperative mortality. Mean follow up was 24 +/- 15 months.

Median waiting time was 55 days. Fifty-five percent of the patients were operated on within the intended waiting time. Postoperative mortality during follow-up was higher in patients operated on after the intended time (8.0 vs 6.2%, p = 0.014), but after correction for age, gender, operative risk, and angina symptoms, waiting time was not an independent predictor for postoperative death (risk ratio, 0.98 per waiting month; 95% confidence interval, 0.97 to 1.00; p = 0.44).

The results suggest that mortality after CABG is not influenced by prolonged waiting time. The result does not exclude subgroups of patients that might benefit from a shorter waiting time.