Abstract 14944: Elevated Peak Immune Monitoring Early After Transplantation is Associated with Angiographic Cardiac Allograft Vasculopathy
Introduction: Early immune monitoring (IM) as measured by adenosine triphosphate release from activated lymphocytes is associated with coronary plaque progression by intravascular ultrasound.
Hypothesis: Elevated IM is also associated with angiographic cardiac allograft vasculopathy (CAV).
Methods: Patients transplanted between January 2007 and December 2011 with early post-transplant IM assays and annual angiographic follow-up were included. IM score was defined as the peak value of assays performed between two-months to mid-year after transplantation. A receivers operating characteristics (ROC) analysis was performed to determine an optimal IM assay cutoff. International Society of Heart Lung Transplantation CAV grading was used, 1 for mild, 2 for moderate, and 3 for severe. Patients were divided into two groups based on the cutoff score, and freedom from angiographic CAV was compared.
Results: 232 patients were included in the analysis. Mean age at transplantation was 56.7 ± 11.8 years and 25.9% were female. Peak IM assays occurred at 104.1 ± 43.7 days after transplantation, with an average of 3.2 ± 1.8 assays measured per patient. A ROC analysis determined an optimal IM assay cutoff of 458 ng ATP/ml. Group 1, n = 178, was defined as having peak IM assays <458 ng ATP/ml. Group 2, n = 54, was defined as having peak IM assays ≥458 ng ATP/ml. Mean peak IM assays for Group 1 and Group 2 were 243.1 ± 115.5 and 592.9 ± 155.5 ng ATP/ml, respectively. Mean clinical and angiographic follow-up were 4.0 ± 1.5 and 3.5 ± 1.6 years, respectively. As demonstrated in Figure 1, CAV1 occurred in 80 of 178 patients (44.9%) in Group 1, and 35 of 54 patients (64.8%) in Group 2, p-value 0.008 (Log Rank). CAV2/3 occurred in 6 of 178 patients (3.4%) in Group 1, and 8 of 54 patients (14.8%) in Group 2, p-value 0.002.
Conclusions: Early elevated peak IM is associated with decreased freedom from angiographic CAV and suggests the potential use of IM in the tailoring of immunosuppression regimens for preventing CAV.
Author Disclosures: R. Cheng: None. B. Azarbal: None. A. Yung: None. F. Liou: None. J.K. Patel: Research Grant; Significant; Alexion Pharmaceuticals. J.A. Kobashigawa: Honoraria; Significant; XDx Inc., Novartis Pharmaceuticals Inc., TransMedics, Inc..
- © 2014 by American Heart Association, Inc.