title: Coronary plaque composition assessed by intravascular ultrasound virtual histology: association with long-term clinical outcomes after heart transplantation in young adult recipients.
abstract: OBJECTIVE
  To assess coronary plaque composition by virtual histology intravascular ultrasound (VH-IVUS) analysis in young adult recipients and to correlate these findings with time from heart transplant (HTx) and long-term outcomes.
  
  
  BACKGROUND
  Rapid progression of coronary allograft vasculopathy after heart transplantation is a powerful predictor of mortality and clinical events at long-term.
  
  
  METHODS
  Forty consecutive young adult recipients transplanted during childhood undergoing VH-IVUS during coronary surveillance have been prospectively included in this study. According to the time interval from HTx to VH-IVUS assessment, our cohort was divided into two groups (group A: ≤5 years, n = 13; group B: >5 years, n = 27).
  
  
  RESULTS
  Group B showed an higher percentage of necrotic core and dense calcium (12 ± 2 vs. 5 ± 1%, P = 0.04; 8.2 vs. 2.1%, P = 0.03; respectively). An "inflammatory plaque" (necrotic core and dense calcium ≥30%) was detected in 34.8% of patients in group B and in none among group A patients (P = 0.03). Patients in group B had a number of adverse clinical events significantly higher than group A patients (53.8 vs. 14.3%; HR 4.45; 95% CI 1.62-12.16; P = 0.029) at long-term follow-up (4.2 years). The multivariate regression analysis showed that age (HR 1.5; 95% CI 1.1-2.0; P = 0.007), time from HTx (HR 1.8; 95% CI 1.6-4.8; P = 0.02), and inflammatory plaque (HR 2.4; 95% CI 1.1-5.3; P = 0.03) were independent predictors of adverse clinical events.
  
  
  CONCLUSIONS
  This study supports the hypothesis that time-dependent differences in plaque composition, as assessed by VH-IVUS, occur after HTx in young adult recipients, probably determining an increased risk of long-term clinical events.
authors.affiliation: Department of Cardiovascular Sciences, European Hospital, Rome.
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Tomai
authors.forename: Rachele
authors.initials: R
authors.lastname: Adorisio
authors.forename: Leonardo
authors.initials: L
authors.lastname: De Luca
authors.forename: Mara
authors.initials: M
authors.lastname: Pilati
authors.forename: Alessandro
authors.initials: A
authors.lastname: Petrolini
authors.forename: Anna S
authors.initials: AS
authors.lastname: Ghini
authors.forename: Francesco
authors.initials: F
authors.lastname: Parisi
authors.forename: Giacomo
authors.initials: G
authors.lastname: Pongiglione
authors.forename: Maria Giulia
authors.initials: MG
authors.lastname: Gagliardi
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000209:etiology / Q000401:mortality; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D005260:Female; D016027:Heart Transplantation / Q000009:adverse effects* / Q000401:mortality; D006801:Humans; D007558:Italy; D053208:Kaplan-Meier Estimate; D008297:Male; D015999:Multivariate Analysis; D009336:Necrosis; D058226:Plaque, Atherosclerotic; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D018084:Ultrasonography, Interventional; D061205:Vascular Calcification / Q000000981:diagnostic imaging / Q000209:etiology; D055815:Young Adult
keywords: coronary allograft vasculopathy; heart transplantation; virtual histology intravascular ultrasound; young adult recipients