Coronary Artery Disease Detected by Coronary CT Angiography Is Associated with Intensification of Preventive Medical Therapy and Lower LDL Cholesterol
Background—Coronary Computed Tomography Angiography (CCTA) is an accurate test for the identification of coronary artery disease (CAD), yet the impact of the CCTA results upon subsequent medical therapy and risk factors has not been widely reported.
Methods and Results—We identified consecutive patients >18 years of age without prior CAD who underwent CCTA from 2004 - 2011 and had complete data on medications before and after CCTA. CCTA results were categorized as no CAD, <50% stenosis, and ≥ 50% stenosis. Based on the number of involved segments, extent of disease was categorized as non-extensive (≤4 segments) or extensive CAD (>4 segments). Electronic medical records and patient interviews were reviewed blinded to CCTA findings to assess initiation of aspirin and intensification of lipid lowering therapies. Survival analysis was performed to evaluate intensification of lipid therapy as a predictor of cardiovascular death or nonfatal myocardial infarction (MI). Among 2839 patients with mean follow-up 3.6 years, the odds of physician intensification of lipid lowering therapy significantly increased for those with non-obstructive CAD (OR 3.6, 95% CI 2.9 - 4.9, p < 0.001) and obstructive CAD (OR 5.6, 95% CI 4.3 - 7.3, p<0.001). Low density lipoprotein (LDL) cholesterol levels declined significantly in association with intensification of lipid lowering therapy after CCTA in all patient subgroups. In a hypothesis generating analysis, among patients with non-obstructive but extensive CAD, statin use after CCTA was associated with a reduction in cardiovascular death or MI (HR 0.18, 95% CI 0.05 - 0.66, p = 0.01).
Conclusions—Abnormal CCTA findings are associated with downstream intensification in statin and aspirin therapy. In particular, CCTA may lead to increased use of prognostically beneficial therapies in patients identified as having extensive, non-obstructive CAD.
- Received June 10, 2013.
- Accepted June 1, 2014.