Low-Density Lipoprotein Cholesterol Level Trends and the Development of Cardiac Allograft Vasculopathy After Heart Transplantation

BACKGROUND: Unlike the relationship with atherosclerotic coronary artery disease, that between low-density lipoprotein cholesterol (LDL-C) and cardiac allograft vasculopathy (CAV) is unclear. Our objectives were to characterize lipid profiles early after heart transplantation (HT) and evaluate the relationship between early LDL-C and the development of CAV. METHODS: We retrospectively reviewed consecutive adults who underwent HT at 2 centres during the time period 2010-2018. The primary outcome was the incidence of angiographic CAV. The relationship between LDL-C and CAV was assessed using Cox proportional hazards and logistic regression models adjusted a priori for clinically important covariates, including recipient and donor age, recipient sex, ischemic time, and pre-HT diabetes. RESULTS: A total of 386 patients followed for a median (range) of 4.4 (2.8-6.8) years were included. LDL-C at baseline (2.11 ± 0.86 mmol/L) and 1 year after HT (2.20 ± 0.88 mmol/L) was similar (P = 0.21), but it was lower at the end of follow-up (1.89 ± 0.74 mmol/L, P < 0.01). Of 309 patients who underwent angiography, 54% had CAV. The risk of CAV did not vary according to baseline, 1-year, or change from baseline to 1-year LDL-C. The odds of CAV at 1 year were equally likely across LDL-C values (adjusted odds ratio 1.00, 95% confidence interval: 0.61-1.63 for baseline, and adjusted odds ratio 1.25, 95% confidence interval: 0.74-2.10 for 1-year LDL-C). CONCLUSIONS: No association was identified between early LDL-C and the development of CAV. Our findings do not support targeting a specific LDL-C for patients who do not otherwise meet criteria for guideline-recommended LDL-C target levels. Randomized studies are warranted to determine if lipid-lowering to a specific LDL-C target level modifies the risk of CAV.