Abstract 14766: Cardiovascular Event Risk Among Patients with Suspected Coronary Artery Disease But No Medically Modifiable Risk Factors: Results from an International Multicenter Study of 5252 Patients

Abstract

Symptomatic patients with suspected coronary artery disease (CAD) often have additional risk factors_including diabetes, hypertension and dyslipidemia_which are associated with increasing rates of CAD frequency and risk. To date, the prevalence, extent, severity and risk of CAD in patients with suspected CAD but with no medically modifiable risk factors has not been adequately examined.

Methods: From an international multicenter cohort study of 27,725 consecutively undergoing coronary computed tomographic angiography (CCTA) from 12 centers, we identified 5252 patients without known CAD with no modifiable CAD risk factors. CAD severity was defined as none (0%), mild (1% to 49%) and obstructive (> 50%) stenosis, and was assessed on a per-patient, per-vessel, and per-segment basis. CAD prescence, extent and severity was related to incident major adverse cardiovascular event (MACE)_inclusive of death, myocardial infarction, unstable angina, or late coronary revascularization_and was estimated using multivariable Cox hazards models.

Results: At a 2.3 + 1.1-year follow-up, MACE occurred in 104 patients. In risk-adjusted analysis, per-patient obstructive (hazard ratio [HR]: 6.64; 95% confidence interval [CI]: 3.68 to 12.00; p< 0.001) CAD were related to MACE. Incident MACE was associated with a dose-response relationship to the number of coronary vessels exhibiting obstructive CAD, with increasing risk forobstructive 1-vessel (HR: 6.11; 95% CI: 3.22-11.60; p<0.001), 2-vessel (HR: 5.86; 95% CI: 2.75-12.50; p<0.0001), or 3-vessel or left main (HR: 11.69; 95% CI:5.38-25.40; p<0.001) CAD. The absence of CAD by CCTA was associated with a low rate of incident MACE (annualized MACE rate: 0.31%). When stratified by age <65 years vs >=65years, younger patients experience higher hazards ratios for MACE for 1 vessel (HR: 8.69; 95% CI:4.01-18.8; p<0.0001 vs. HR: 6.86; 95% CI: 2.26-20.9; p<0.0003) and 2 vessel obstructive disease (HR: 12.17; 95% CI: 4.66-31.8; p<0.0001 vs. HR: 6.32; 95% CI: 1.90 to 21.0; p<0.0001). Men and women experienced similar hazards for MACE.

Conclusions: Among individuals with suspected CAD but with no modifiable risk factors, CAD prevalence is common with significantly increased hazards for MACE including myocardial infarction.