Coronary Plaque Characteristics in Patients With Chronic Kidney Failure: Impact on Cardiovascular Events and Mortality

Abstract

BACKGROUND: In patients with coronary artery disease, coronary plaques with high-risk features and low-attenuation plaque burden are independent measures associated with major adverse cardiovascular events (MACEs). Patients with chronic kidney failure may have different coronary artery disease characteristics. The aim was to assess the association of coronary plaque characteristics and coronary artery disease extent with MACE and all-cause mortality in patients with chronic kidney failure. METHODS: Potential kidney transplant candidates who underwent coronary computed tomography angiography as part of the cardiac screening program before kidney transplantation were included. We evaluated high-risk plaques and diameter stenosis semiqualitatively and quantified coronary artery calcium score and plaque burden (percentage atheroma volume). RESULTS: In 484 patients with chronic kidney failure and few or no symptoms of coronary artery disease (mean age, 53±12 years; 62% men; 32% on dialysis), 56 (12%) patients suffered MACE and 69 (14%) patients died during a median follow-up of 4.9 years. High-risk plaques were present in 39 (70%) patients with MACE. Median calcified plaque burden was 3.7% in patients with MACE versus 0.2% in patients without MACE. The median low-attenuation plaque burden was 0.3% versus 0.03%, respectively. In semiqualitative analyses, the presence of high-risk plaque and a higher coronary artery calcium score were associated with increased risk of MACE (hazard ratio (HR), 2.0 [95% CI, 1.0–3.7]; P =0.040; HR, 1.2 [95% CI, 1.0–1.3]; P =0.014), respectively. Neither were associated with all-cause mortality. In quantified analysis, increasing levels of both calcified and low-attenuation plaque burdens were associated with risk of MACE (HR, 2.6 [95% CI, 1.8–3.7]; P <0.001; HR, 2.6 [95% CI, 1.5–4.5]; P =0.001 [per variable doubling, respectively]) and all-cause mortality (HR, 1.6 [95% CI, 1.2–2.1]; P =0.002; HR, 1.8 [95% CI, 1.1–3.0]; P =0.028, respectively). CONCLUSIONS: In patients with chronic kidney failure, calcified and low-attenuation plaque burdens were independently associated with MACE and all-cause mortality, while high-risk plaques and coronary artery calcium score were only associated with MACE. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01344434.