Factors associated with cardiac allograft vasculopathy after heart transplantation

Introduction
Cardiac allograft vasculopathy (CAV) is a major threat to long-term survival after heart transplantation (HT). Aim: To determine factors associated with CAV detection in patients after HT.

Material and methods
We analyzed 299 consecutive patients after HT who underwent routine visits at our institution between 2016 and 2018. Human interleukin 33 (IL-33) and suppression of tumorigenicity 2 (ST2) were measured by sandwich enzyme-linked immunosorbent assay with a commercially available kit (Human ST-2 and IL-33 ELISA, SunRedBio Technology Co, Ltd, Shanghai, China).

Results
The patients’ median age was 59.00 years, and 74.2% were men. The frequency of CAV was 47.5%. Multivariable logistic regression analysis showed that IL-33 (odds ratio (OR) = 1.044 (1.029–1.059), p < 0.001) and ST2 (OR = 1.061 (1.040–1.083), p < 0.001) serum concentrations, donor age (OR = 1.046 (1.009–1.085), p = 0.015), left ventricular diastolic dimension (LVDD) (OR = 1.081 (1.016–1.149), p = 0.013), and time from HT to blood collection (OR = 1.256 (1.151–1.371), p < 0.001) were independent risk factors for CAV. The area under the receiver operating characteristics curve (AUC) indicated good prognostic power of IL-33 and ST2 concentrations (AUC = 0.779 and AUC = 0.784, respectively) and excellent prognostic power of the IL-33/ST2 score (AUC = 0.863).

Conclusions
Lower IL-33 and higher ST2 serum concentrations, as well as older donor age, larger LVDD and longer time from HT to blood collection, are independently associated with CAV. IL-33 and ST2 have good discriminatory power and the IL-33/ST2 score has excellent strength for detecting CAV.