MedicalResearch.com Interview with:
Harindra C. Wijeysundera MD PhD FRCPC
Interventional Cardiology, Schulich Heart Centre, Sunnybrook Health Sciences Centre
Scientist, Sunnybrook Research Institute (SRI)
Assistant Professor, Dept. of Medicine & Institute of Health Policy, Management and Evaluation
University of Toronto Adjunct Scientist, Institute for Clinical Evaluative Sciences (ICES)
Toronto, ON, Canada
Medical Research: What is the background for this study? What are the main findings?
Dr. Wijeysundera: Given the rapid increase in health care costs, there has been growing emphasis on the more rational use of resources. One such effort is the development of appropriate use criteria. Such criteria have been developed in many areas of medicine, including in cardiology for diagnostic angiography. The underlying rationale for a test to be appropriate is that its anticipated benefit outweighs its anticipated harms. However, there is a paucity of empirical evidence validating this conceptual framework. Our goal was to validate the 2012 appropriate use criteria for diagnostic coronary angiography, by examining the relationship between the appropriateness of a coronary angiography in patients with suspected stable ischemic heart disease and the proportion of patients who were found to have obstructive coronary artery disease. We used data obtained from the Cardiac Care Network registry of Ontario, Canada. This is a population based registry of all cardiac procedures in the province of Ontario. We examined 48,336 patients and found that 58.2% of angiographic studies were classified as appropriate, 10.8% were classified as inappropriate, and 31.0% were classified as uncertain. Overall, 45.5% of patients had obstructive CAD. In patients with appropriate indications for angiography, 52.9% had obstructive CAD, with 40.0% undergoing revascularization. In those with inappropriate indications, 30.9% had obstructive CAD and 18.9% underwent revascularization; in those with uncertain indications, 36.7% had obstructive CAD and 25.9% had revascularization. Although more patients with appropriate indications had obstructive CAD and underwent revascularization (P < 0.001), a substantial proportion of those with inappropriate or uncertain indications had important coronary disease. Our conclusion was that despite the association between appropriateness category and obstructive CAD, this study raises concerns about the ability of the appropriate use criteria to guide clinical decision making.