title: Left ventricular myocardial performance index change for detection of acute cellular rejection in pediatric heart transplantation.
abstract: EMB, the gold standard for diagnosis of ACR, poses unique risks in children. Limited cross-sectional data have associated LV MPI with ACR. We hypothesize that a relative change in MPI from baseline without ACR to the time of ACR will better detect ACR than an absolute threshold LV MPI value. We identified 40 children with ACR ≥60 days post-transplant matching them by age and time from transplantation to 40 children without ACR. There was a significant increase in LV MPI at time of ACR vs. baseline (0.59 ± 0.17 vs. 0.41 ± 0.11; p < 0.001). There was no difference in LV MPI between baseline and follow-up (0.41 ± 0.11 vs. 0.42 ± 0.11; p = 0.65). An absolute increase in LV MPI of ≥0.47 had 82.5% sensitivity and 85% specificity for ACR, whereas an increase in LV MPI from baseline of ≥20.4% was 90% sensitive and 100% specific. Serial measurement of LV MPI appears to be a sensitive and specific marker of ACR. LV MPI shows good interobserver agreement and increases at the time of EMB-proven ACR with subsequent resolution to baseline measurements upon EMB-proven resolution of ACR. Future studies in larger, prospective cohorts should be undertaken to validate these findings.
authors.affiliation: Division of Pediatric Cardiology, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, PA, USA; Womack Army Medical Center, Fort Bragg, NC, USA.
authors.forename: Ryan
authors.initials: R
authors.lastname: Flanagan
authors.forename: Nicole
authors.initials: N
authors.lastname: Cain
authors.forename: Gregory H
authors.initials: GH
authors.lastname: Tatum
authors.forename: Mark G
authors.initials: MG
authors.lastname: Debrunner
authors.forename: Stacey
authors.initials: S
authors.lastname: Drant
authors.forename: Brian
authors.initials: B
authors.lastname: Feingold
mesh_terms: D000293:Adolescent; D000328:Adult; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D003971:Diastole; D004452:Echocardiography; D005260:Female; D006084:Graft Rejection / Q000175:diagnosis*; D006333:Heart Failure / Q000628:therapy*; D016027:Heart Transplantation; D006801:Humans; D007223:Infant; D008297:Male; D009206:Myocardium / Q000473:pathology; D015588:Observer Variation; D011446:Prospective Studies; D012372:ROC Curve; D015427:Reperfusion Injury / Q000473:pathology; D012306:Risk; D012680:Sensitivity and Specificity; D013997:Time Factors; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000473:pathology*; D016277:Ventricular Function, Left / Q000502:physiology*; D055815:Young Adult
keywords: acute rejection; echocardiogram; heart transplant; myocardial performance index; pediatric