Clonal Hematopoiesis of Indeterminate Potential and Long-term Outcomes in Heart Transplantation

Abstract

BackgroundClonal hematopoiesis of indeterminate potential (CHIP) mutations, an aging trait, has been associated with progression of cardiovascular disease and development of malignancy. Uncertainty prevails regarding a robust association between CHIP and heart transplantation outcomes. ObjectivesTo determine prevalence of CHIP mutations in heart transplantation and their association with long-term outcomes including cardiac allograft vasculopathy (CAV), graft failure, malignancy, and all-cause mortality. MethodsWe conducted a mixed retrospective-prospective observational study of heart transplant recipients with targeted sequencing for CHIP mutations (Variant allele frequency (VAF) of ≥2%). The primary composite outcome was first occurrence of CAV grade ≥2, graft failure, malignancy, cardiac re-transplantation, or all-cause death. Secondary outcomes were the individual components of the composite primary outcome. Sensitivity analyses with base-case and extreme scenarios were performed. ResultsAmong 95 HT recipients, 30 had CHIP mutations (31.6%). DNMT3A mutations were most common (44.7%) followed by PPM1D (13.2%), SF3B1 (10.5%), TET2 (7.9%) and TP53 (7.9%). The only significant independent predictor of CHIP was age at enrollment or age at transplantation. After multivariable adjustment, CHIP was not associated with the primary outcome which occurred in 44 (46.3%) patients (HR=0.487; 95%CI:0.197-1.204; p=0.119), malignancy alone or death. ConclusionWe demonstrated no association between CHIP mutations and post-transplant outcomes including CAV, graft failure, malignancy, and all-cause mortality. In line with previously published data, our analysis provides additional evidence on the lack of clinical value of using CHIP mutations as a biomarker for surveillance in outcomes after heart transplantation.