ANALYSIS OF DEATHS WHILE WAITING FOR CARDIAC-SURGERY AMONG 29 293 CONSECUTIVE PATIENTS IN ONTARIO, CANADA

Objectives-To assess death rates among patients waiting for cardiac va lve surgery or isolated coronary artery bypass surgery (CABG), and to determine independent risk factors for death while waiting for isolate d CABG. Design-Prospective cohort analysis based on an inclusive regis try. Setting-Nine cardiac surgical units in Ontario, Canada. Patients- 29 293 consecutive patients scheduled for cardiac surgery between Octo ber 1991 and June 1995. Main outcome measures-Death rates while waitin g for surgery were determined among patients scheduled for isolated CA BG, isolated valve surgery, or combined procedures. Predictors of deat h among patients with isolated CABG were determined from multivariate analysis. Results-There were 141 deaths (0.48%) among 29 293 patients. Adjusting for age, sex, and waiting time, patients waiting for valve surgery had a significantly increased risk of death compared with pati ents waiting for CABG alone (adjusted odds ratio 1.88, 95% confidence interval (CI) 1.23 to 2.88, p = 0.004). Results were similar for patie nts waiting for combined valve and CABG procedures compared with those who were waiting for isolated CABG. Independent risk factors for deat h while waiting for isolated CABG included: impaired left ventricular function (odds ratio 2.47, 95% CI 1.59 to 3.84, p < 0.001); advancing age (for each decade, odds ratio 1.41, 95% CI 1.10 to 1.80, p = 0.007) ; male sex (odds ratio 1.95, 95% CI 1.00 to 3.81, p = 0.05); and waiti ng longer than the maximum time recommended in Canadian guidelines for a patient's clinical profile (odds ratio 1.59, 95% CI 1.01 to 2.51, p = 0.044). After scaling waiting time to surgery or death continuously in days, the same predictors emerged. Conclusions-Patients waiting fo r valve surgery have a higher risk of death than patients waiting for isolated CABG. Guidelines to promote safer and fairer queuing for non- CABG cardiac surgery are needed. Shorter waiting Lists, better complia nce with existing guidelines, and guideline revisions to upgrade patie nts with left ventricular dysfunction could generate additional reduct ions in the already low risk of death for patients waiting for isolate d CABG.