Hawkes et al (Senes-Ferrari 1999). However, more recently in Australia, the rates of CABG have fallen to 90–100 procedures/100 000 in 1999 (comparable with the Netherlands, New Zealand, and Finland), and 70–80 procedures/100 000 in 2001 (AIHW and NHFA 2004). In comparison, in 1999 the United States had the highest rates of CABG of 16 OECD countries and their age- standardized procedure rates were twice those of Australia (AIHW and NHFA 2004). The CABG operation has become the most completely studied operation in the history of surgery. It has been shown to be highly effective for the relief of severe angina, and to have prolonged life in subsets of patients. Nonetheless, the role of CABG is being re-evaluated as a consequence of new technologies, both in coronary surgery and in percutaneous coronary intervention (Kirklin et al 1991; Caines et al 2004). Indications for CABG The CABG procedure is indicated for the relief of symptoms (primarily angina) unresponsive to medical treatment or percutaneous transluminal coronary angioplasty (PTCA), particularly when it is likely that this operation will delay unfavorable events (death, myocardial infarction, angina recurrence) longer than other forms of treatment. For angina relief, surgery has often succeeded where medical or interventional therapy has failed or is not recommended. For survival, the situation is more complex. There is general agreement that CABG improves prognosis in the early post- surgical years in those patients with symptomatic left main coronary artery stenosis or stenosis of the three main coronary vessels, although this advantage is not thought to be significant after 10–12 years (Cundiff 2002; Hlatky et al 2004). However, for the majority of patients with less severe pathology, the prognosis is good without surgery (Kirklin et al 1991; Caines et al 2004). Furthermore, cardiac surgery has advanced to a point where mortality rates have declined dramatically (Ferguson et al 2002). Thus, with such low death rates, selection among alternative courses of cardiac therapy is increasingly being based on measures of quality of life (QOL), including minimization of pain and disability. Measurement of quality of life following CABG The measurement of treatment outcome or QOL for the patient is the keystone of modern scientific medicine. The importance of treatment outcome is recognized throughout clinical practice, particularly when innovative, invasive or costly treatments are evaluated, and the mortality rate is too low to 478 affect decision making (Caine et al 1991). However, there is no universal agreement of the meaning of QOL or how it should be measured (Wenger et al 1995). Following cardiac intervention, outcomes have been evaluated in terms of mortality, and complications or recurrence of symptoms, as they are easy to measure (Caine et al 1991; Wenger et al 1995; Chocron et al 1996). However, these measures do not provide a complete assessment of an individual’s capabilities at home, at work, or in the community (McCarthy et al 1995). Hence, the study of outcomes of cardiac intervention has been characterized by changes in the questions asked in evaluation, changes in the technologies used to answer these questions, and changes in the sources of assessment information. Outcomes of CABG can be grouped into categories that reflect the expected goals of CABG such as: prolongation of life, reduction of symptoms, improvement in physical, psychological and social functioning, and improvement in vocational status (Duits et al 1997). Prolongation of life Prolongation of life as an outcome of CABG was initially addressed in three major randomized clinical trials that compared CABG with medical therapy. They include the Veterans Administration Study (VAS), (Grover et al 1990) the European Coronary Artery Surgery Study (ECASS), (European Coronary Surgery Study Group 1982) and the Coronary Artery Surgery Study (CASS) (CASS PI 1983; Serruys et al 2005). The VAS recruited 1015 patients from 13 centers between 1970 and 1974. Patients were randomly allocated to medical or surgical treatment. The study revealed no significant difference in mortality 4 years after CABG in patients with one-, two- or three-vessel disease, although a highly significant increase in survival rate was observed in a subset of patients who underwent CABG for left main coronary artery obstruction. The 4-year mortality for CABG patients was 7% (n = 46), compared with 33% for medical treatment (n = 44) (Hampton 1984). The ECASS recruited 768 men under 65-years between 1973 and 1976. While the participants were randomized to medical or surgical treatment, the main weakness of this trial was that nothing was known about the original population from which the trial patients were drawn. There was significant improvement in survival for the total CABG population, and for patients with three-vessel disease, with stenosis in the proximal third of the left anterior descending artery, or with left main coronary disease. After 5 years of follow up, 30 deaths were reported among the 395 patients treated surgically Vascular Health and Risk Management 2006:2(4)