Quilty Effect Correlates With Biopsy-proven Acute Cellular Rejection But Does Not Predict Transplanted Heart Coronary Artery Vasculopathy

Abstract

The appropriate therapy after orthotopic heart transplantation (OHT) is determined by the results of endomyocardial biopsies (EMBs). The Quilty effect (QE) is a recognized cause of discrepancies in EMB grading, but its clinical implications remain unclear. In this study we assess the correlation of the QE with biopsy-proven acute cellular rejection (AR) and coronary artery vasculopathy (CAV). We reassessed 5,361 EMB samples, obtained from 429 patients, based on QE occurrence and its impact on EMB score. Next, we divided all patients with at least 1 year of follow-up into two groups: a QE(+) group (n = 202, 58.7% of sample, 172 males/30 females, 44.8 +/- 12 years of age) and a QE(-) group (n = 142, 41.3% of sample, 124 males/18 females, 45.4 +/- 12 years of age), and compared AR and CAV occurrences. The QE was observed in 669 EMBs (12.5%), and at least 1 EMB with QE was found among the 231 patients (53.8%). The initial QE occurrence took place during the first 3 months after OHT in 68% of QE(+) patients, and >1 year post-OHT in 13% of patients. The average EMB score was significantly higher in QE(+) biopsies. A comparison of the two groups revealed a significantly higher number of AR episodes and number of patients with at least one episode of AR in QE(+) patients. There was no significant difference in number of CAV occurrences between groups. The QE seems to be a marker of the same increased immune system activity that can lead to AR. A relationship between QE and CAV was not supported by the present results.