Obstructive CAD Not Found in Most Elective Catheter Patients
Findings suggest need for better strategies for making decisions on routine catheterization
WEDNESDAY, March 10 (HealthDay News) -- Only about 38 percent of patients without known heart disease who had an elective cardiac catheterization had obstructive coronary artery disease (CAD), suggesting a need for better risk-stratification strategies to improve the diagnostic yield of this procedure in routine clinical practice, according to research published in the March 11 New England Journal of Medicine.
Manesh R. Patel, M.D., of Duke University in Durham, N.C., and colleagues analyzed data from 398,978 patients free of known CAD who underwent elective invasive angiography. The researchers assessed them for obstructive CAD, which they defined as stenosis of at least 50 percent of the diameter of the left main coronary artery or at least 70 percent of the diameter of a major epicardial vessel.
The researchers note that catheterization revealed obstructive CAD in 37.6 percent of the patients. Predictors of disease included male sex (odds ratio, 2.70), older age (odds ratio, 1.29 per five-year increment), and insulin-dependent diabetes or dyslipidemia (odds ratios, 2.14 and 1.62, respectively). Patients with a positive result from a noninvasive test had a moderately higher chance of having obstructive disease compared with those who did not undergo noninvasive testing before angiography (41 versus 35 percent).
"Patel and colleagues suggest that only 38 percent of patients who undergo invasive coronary angiography for diagnostic purposes actually have obstructive CAD -- a decidedly low proportion considering both the adverse events and the radiation exposure associated with invasive coronary angiography," writes the author of an accompanying editorial.
Several authors reported financial relationships with pharmaceutical companies.