Objective: We sought to examine the differential impact of carotid atherosclerosis (CA) on the risk of major adverse coronary and cerebrovascular events (MACCE) in patients with vs. without coronary artery disease (CAD) diagnosed angiographically.
Background: CA is reportedly a strong predictor of imminent cardiac events, even in the absence of established CAD. Previous outcome reports have varied greatly in CAD and carotid artery stenosis (CAS) definitions so the prognostic interplay between CA and future MACCE remains unclear.
Methods: We conducted a follow-up survey of 1,391 patients who underwent clinically-driven coronary angiography and a same-day carotid Doppler study. Follow-up time was defined as the time to either death or MACCE.
Results: Of the 1,391 patients included in the study, angiographic CAD was present in 1,105 patients (79%). The mean follow-up was 1,574 days. Rates of the composite MACCE endpoint were higher among patients with CAD compared to those without CAD (48% vs. 20%, HR=2.1, p<0.001), whereas the rates of all-cause mortality (10% vs. 9%, HR=0.94, p=0.81) and stroke (7% vs. 5%, HR=0.67, p=0.3) did not differ significantly between both groups. By multivariate analysis, the presence of clinically significant CAS (≥50% stenosis) was independently predictive of all-cause mortality (HR=3.08, 95% CI 1.03-9.1, p=0.04) and trended toward an independent association with the composite MACCE endpoint (HR=2.13, 95%CI 0.9-4.9, p=0.08) among patients without CAD. CAS was not independently associated with either outcome among patients with CAD.
Conclusions: The prognostic implications of CAS are predominantly imparted in the absence of preexistent CAD verified by angiography.