Global longitudinal strain (GLS) by speckle-tracking echocardiography is a sensitive measure of regional left and right ventricular (LV and RV) dysfunction, before onset of overt systolic dysfunction. We sought to evaluate the prognostic utility of measuring LV-GLS and RV free wall strain (FWS) in low risk patients at 1 year after orthotopic heart transplantation (OHT). We retrospectively studied 96 OHT recipients (age 52 ± 14 years, 64% men) free of antibody-mediated rejection or moderate to severe coronary allograft vasculopathy (CAV, grade 2 to 3) at 1 year after transplant. LV-GLS and RV-FWS were calculated using EchoPAC software. Cox models were developed after adjusting for the Index for Mortality Prediction After Cardiac Transplantation (IMPACT) score (post-transplant risk score), with the primary outcome of death, moderate to severe CAV, or treated rejection. At 1 year after transplant, LV ejection fraction and RV fractional area change (FAC) were 58 ± 7% and 42 ± 10%, respectively. LV-GLS was -17.0 ± 3.3% and RV-FWS -16.4 ± 4.5%. At an average follow-up of 4.5 years, 28 patients met the primary end point (10 death, 5 vasculopathy, 17 rejection). In sequential Cox models, markers of RV function were associated with the primary outcome (RV-FAC, p = 0.012; RV-FWS, p = 0.022), while LV ejection fraction and LV-GLS were not. We conclude that in low risk patients 1 year after OHT, markers of RV function (RV-FAC and RV-FWS) are independently associated with incident rejection, CAV, and death. Markers of RV dysfunction could potentially be incorporated into risk scores and future prospective studies to risk stratify patients after OHT.
Copyright © 2017. Published by Elsevier Inc.