HEART-BC: Heart Transplant Evaluation Using Advanced Rejection Monitoring Tools - British Columbia

Evaluate whether integration of HeartCare (AlloMap + AlloSure) into routine post-transplant surveillance reduces the number of invasive endomyocardial biopsies (EMBx) in the first year post-transplant

Inclusion Criteria: * Adult (age ≥ 18 years) at the time of transplant * Recipient of a heart transplant at St. Paul's Hospital * Within 1 year of heart transplantation * Followed at the Post-Transplant Clinic in Vancouver, BC * Clinically stable at the time of scheduled HeartCare surveillance (no active hemodynamic compromise or clinical suspicion of rejection at study visit) * Able to provide written informed consent Exclusion Criteria: * Unable to provide informed consent * High immunological risk at transplant: positive flow crossmatch at time of transplant, or donor-specific antibodies (DSA) detected at time of transplant * Multi-organ transplant recipient (e.g., heart-kidney, heart-liver) * Clinical instability: hemodynamic instability, sepsis, or active severe wound infection at the time of a scheduled surveillance visit * Prior severe acute cellular rejection (≥ 3R ISHLT grade) or prior antibody-mediated rejection (pAMR ≥ 2) during the study period * EMBx clinically indicated for suspected rejection at the time of a scheduled HeartCare visit (these recipients remain in the study but their visit is classified as a clinically-indicated EMBx, not a HeartCare visit)