Clonal hematopoiesis confers an increased mortality risk in orthotopic heart transplant recipients

Area of Science:

• Cardiology
• Hematology
• Transplantation Immunology

Background:

• Orthotopic heart transplant (OHT) recipients require improved risk stratification and non-invasive surveillance to minimize post-transplant complications.
• Clonal hematopoiesis (CH), characterized by acquired mutations in hematopoietic stem cells, is associated with inflammation and adverse cardiovascular events.

Purpose of the Study:

• To investigate the association between clonal hematopoiesis (CH) and clinical outcomes in orthotopic heart transplant (OHT) recipients.
• To determine if CH correlates with acute cellular rejection, CMV infection, cardiac allograft vasculopathy (CAV), malignancies, or survival post-OHT.

Main Methods:

• Blood samples from 127 OHT recipients were analyzed using error-corrected sequencing to detect CH-associated mutations.
• The study evaluated the relationship between CH and key post-transplant events including CAV, infections, malignancies, and patient survival.

Main Results:

• CH mutations were identified in 20.5% of OHT recipients, frequently involving DNMT3A, ASXL1, and TET2 genes.
• Patients with CH exhibited a significantly higher incidence of moderate to severe cardiac allograft vasculopathy (CAV) (18% vs. 0%) and a higher mortality rate (42% vs. 15%).
• CH was not significantly associated with acute cellular rejection, CMV infection, or malignancies.

Conclusions:

• The prevalence of CH in OHT recipients is notably higher than in age-matched general populations.
• Clonal hematopoiesis is a significant risk factor for cardiac allograft vasculopathy and mortality in heart transplant recipients.
• CH may serve as a novel non-invasive biomarker for risk stratification in OHT patients.