Waiting for coronary artery bypass surgery: population-based study of 8517 consecutive patients in Ontario, Canada

Summary Deaths and delays in queues for coronary surgery in Canada have been highlighted by American interest groups opposed to "socialised medicine". Since 1991 all nine cardiac surgery centres in Ontario register and follow patients after acceptance for surgery. We examined the experience of 8517 consecutive patients leaving the registry from October 1991 to July 1993. Individual acuity scores were determined based on symptoms, angiographic findings, left ventricular function, and, where available, non-invasive tests of ischaemic jeopardy. Planned surgery was declined or deferred for 3·2% of registrants. While in the queue, 31 (0·4%) patients died and three had surgery indefinitely deferred after a non-fatal myocardial infarction. Among 8213 patients receiving surgery, the median wait was 17 days (inter-quartile range [IQR]: 4, 51), ranging from one day (IQR 0:4) for patients needing very urgent surgery (acuity score 2-3) to 42 days (IQR: 18, 77) for those rated low priority (acuity score 6-7). In a multivariate analysis, the most important determinant of waiting time was symptom status (p