Acute cellular rejection later than one year after heart transplantation: A single-center retrospective study at Skåne University Hospital in Lund 1988-2010

Routine endomyocardial biopsy (EMB) to detect acute cellular rejection (ACR) late (>1 year) after heart transplantation (HT) remains debated. To gain knowledge on late ACR and thereby approach this issue, we studied the incidence, predictors, and outcome of late ACR. 815 late EMBs from 183 patients transplanted 1988-2010 were retrospectively reviewed until June 30, 2012. Only 4.4% of the routine and 17.6% of the additional clinically indicated late EMBs showed ACR ≥ grade 2. With time post-HT, there was a clear trend toward fewer ACRs, a lower incidence of ACR per patient per year, and a deceleration in the decrease in the proportion of patients free from ACR. Sex-mismatching and first-year ACR were associated with an increased risk of late ACR, which also was associated with worse outcome. Although rare, when compared to our previous study on first-year EMBs, it appears as if late more often than early ACR remains undetected and that also late and not only early ACR influences outcome. Extended EMB surveillance >1 year post-HT therefore still seems reasonable in "high-risk" patients, as also suggested in the International Society for Heart and Lung Transplantation guidelines. These should include, but not be limited to, the two risk groups above.