Normal coronary rates for elective angiography in the veterans affairs healthcare system: Insights from the VA CART program (Veterans Affairs Clinical Assessment Reporting and Tracking)

Objectives This study sought to determine if an integrated healthcare system is selective and consistent in the use of angiography, as reflected by normal coronary rates. Background Rates of normal coronary arteries with elective coronary angiography vary considerably among U.S. community hospitals. This variation may in part reflect incentives in fee-for-service care. Methods Using national data from the Veterans Affairs (VA) Clinical Assessment Reporting and Tracking (CART) program representing all 76 VA cardiac catheterization laboratories, we evaluated all patients who underwent elective coronary angiography from October 2007 to September 2010. Normal coronary angiography was defined as <20% stenosis in all vessels. To assess hospital-level variation in normal coronary rates, we categorized hospitals by quartiles as defined by their proportion of normal coronaries. Results Overall, 4,829 of 22,538 patients (21.4%) had normal coronary angiography. Hospital proportions of normal coronaries varied markedly (median hospital proportion 20.5%; interquartile range: 15.1% to 25.3%; range: 5.5% to 48.5%). Categorized as hospital quartiles, the median proportion of normal coronaries in the lowest quartile was 10.8%, as compared with a median proportion of 19.1% in the second lowest quartile, 23.1% in the second highest quartile, and 30.3% in the highest quartile. Hospitals with lower rates of normal coronaries had higher rates of obstructive coronary disease (59.2% vs. 51.3% vs. 52.6% vs. 44.3%; p < 0.001) and subsequent revascularization (38.1% vs. 33.9% vs. 31.5% vs. 29.3%; p < 0.001). Conclusions Approximately 1 in 5 patients undergoing elective coronary angiography in the VA had normal coronaries. This rate is lower than prior published studies in other systems. However, the observed hospital-level variation in normal coronary rates suggests opportunities to improve patient selection for diagnostic coronary angiography.