Heart transplant graft survival is improved after a reduction in panel reactive antibody activity

Abstract

Background: Allosensitization in potential orthotopic heart transplant recipients is evaluated with the panel reactive antibody assay. Sensitized patients have prolonged wait times and increased waitlist and post-transplant mortality. Although low panel reactive antibody activity at the time of orthotopic heart transplantation is associated with improved outcomes, literature regarding the survival benefit of a panel reactive antibody reduction in the sensitized orthotopic heart transplant recipient remains limited.

Methods: Adult orthotopic heart transplant recipients listed in the United Network for Organ Sharing database (October 1, 1987, to June 29, 2004) were stratified by peak panel reactive antibody activity and whether a substantial decline from peak to most recent panel reactive antibody activity occurred before transplant. Propensity matching adjusted for differences in recipient and donor characteristics. Graft survival was assessed with Kaplan-Meier analysis. Cox proportional hazards regression determined predictors of graft survival.

Results: Pretransplant characteristics differed between sensitized patients who had a substantial decline in panel reactive antibody activity and those who did not. Propensity matching compensated for these differences. Kaplan-Meier survival analysis of matched groups showed that the median graft survival was 120 months in patients with a significant panel reactive antibody reduction and 103 months in patients with a trivial reduction (P = .007, log-rank). In Cox proportional hazards modeling, a significant reduction in panel reactive antibody activity had an independent protective effect on graft survival (hazard ratio, 0.88; confidence interval, 0.80-0.96; P = .006).

Conclusions: Sensitized patients who had a substantial reduction in panel reactive antibody activity had an associated decline in the incidence of graft failure compared with those without a panel reactive antibody activity reduction. These results support efforts to reduce panel reactive antibody activity before orthotopic heart transplantation in patients with high panel reactive antibody activity.