Slowed Progression of Maximal Intimal Thickening by Intravascular Ultrasound after Initiation of Sirolimus
1Children's Hospital Colorado, Aurora, CO, 2University of Florida Health, Gainesville, FL
Meeting: 2019 American Transplant Congress
Abstract number: B113
Keywords: Heart/lung transplantation, Intimal, Pediatric, Sirolimus (SLR)
Session Information
Session Name: Poster Session B: Heart and VADs: All Topics
Session Type: Poster Session
Date: Sunday, June 2, 2019
Session Time: 6:00pm-7:00pm
Presentation Time: 6:00pm-7:00pm
Location: Hall C & D
*Purpose: Evidence in adult heart transplant (HT) patients (pt) shows that initiating sirolimus (SRL) slows progression of cardiac allograft vasculopathy (CAV) measured by intravascular ultrasound (IVUS). However, no data exist in children. We evaluated changes in maximal intimal thickness (MIT) using serial IVUS measurements in children who initiated SRL for increased MIT post-HT.
*Methods: A single center retrospective review of all pt who underwent pediatric HT and initiated SRL after diagnosis (dx) of increased MIT. We included pt with at least one IVUS before and after starting SRL and excluded re-HT. Repeated measures were analyzed with a univariable linear mixed model with a breakpoint at the time of SRL initiation to account for differing numbers of IVUS studies between pt. The F test compared the difference in slopes before vs. after starting SRL.
*Results: Thirty-four pt met inclusion criteria and had HT between 1991 – 2007 with IVUS performed between 1995 – 2018. Mean age at HT was 5.5 ± 6.2 yr and 68% were male. Pre-HT dx was cardiomyopathy in 15 and congenital in 19. Mean number of rejection episodes was 1.9 ± 1.6 before SRL and 0.4 ± 0.8 after SRL (p<0.0001). There was a total of 246 IVUS evaluations, 147 before (4.3 ± 2.4 per pt) and 99 after (2.9 ± 1.9 per pt) initiation of SRL. Mean age at 1st IVUS evaluation was 10.5 ± 4.9 yrs. Mean time from HT to start of SRL was 11.1 ± 5.4 yr. Mean time from 1st IVUS to start of SRL was 6.2 ± 4.4 yr with a mean f/u time of 3.2 ± 2.5 yr after initiating SRL. Mean MIT at 1st IVUS was 0.18 ± 0.17 mm and increased significantly to 0.68 ± 0.48 mm prior to start of SRL (p<0.0001). Mean MIT did not change significantly from start of SRL to last follow-up (0.68 ± 0.48 vs 0.75 ± 0.4 mm; p = 0.4). The difference in the slopes of mean MIT before and after initiation of SRL is shown in Figure 1.
*Conclusions: SRL initiation was associated with a decrease in progression of MIT by IVUS in pediatric HT pt. This suggests that intimal thickening after pediatric HT may be mitigated by incorporating SRL into maintenance immunosuppression.
To cite this abstract in AMA style:
Putschoegl A, Campbell K, Everitt M, Miyamoto S, Pietra B, Auerbach S. Slowed Progression of Maximal Intimal Thickening by Intravascular Ultrasound after Initiation of Sirolimus [abstract]. Am J Transplant. 2019; 19 (suppl 3). https://atcmeetingabstracts.com/abstract/slowed-progression-of-maximal-intimal-thickening-by-intravascular-ultrasound-after-initiation-of-sirolimus/. Accessed May 8, 2025.« Back to 2019 American Transplant Congress