Impact of routine surveillance biopsy intensity on the diagnosis of moderate to severe cellular rejection and survival after pediatric heart transplantation.

Data are lacking on RSB intensity and outcomes after pediatric heart transplantation. PHTS centers received a survey on RSB practices from 2005 to present. PHTS data were obtained for 2010-2013 and integrated with center-matched survey responses for analysis. Survey response rate was 82.6% (38/46). Centers were classified as low-, moderate-, and high-intensity programs based on RSB frequency (0-more than 8 RSB/y). RSB intensity decreased with increasing time from HT. Age at HT impacted RSB intensity mostly in year 1, with little to no impact in later years. Most centers have not replaced RSB with non-invasive methods, but many added ECHO and biomarker monitoring. Higher RSB intensity was not associated with decreased 4-year mortality (P=.63) or earlier detection of moderate to severe (ISHLT grade 2R/3R) cellular rejection (RSBMSR) in the first year (P=.87). First-year RSBMSR incidence did not differ with intensity or age at HT. Significant variability exists in RSB intensity, but with no impact on timing and incidence of RSBMSR or 4-year mortality. Reduction in RSB frequency may be safe in certain patients after pediatric HT.