Evaluation of left atrial remodeling in kidney transplant patients using cardiac magnetic resonance imaging

Background Increased left atrial (LA) size predicts cardiovascular events in patients with end-stage kidney disease. There is a paucity of data on LA changes after kidney transplantation (KT). Accordingly, we used cardiac magnetic resonance imaging (CMR) to evaluate LA remodeling after KT, and examined its relationship with left ventricular (LV) measurements, blood pressure and cardiac biomarkers. Methods In this prospective multi-center cohort study, 39 pre-transplant dialysis patients underwent KT and 42 eligible transplant recipients remained on dialysis. CMR, blood pressure and serum measurements for N-terminal pro b-type natriuretic peptide (NT-proBNP), high sensitivity C-reactive protein (hsCRP), and growth differentiation factor-15 (GDF-15) were performed at baseline and 12 months. Results After 12 months, there were no significant changes in LA end-systolic volume index, LA end-diastolic volume index, or LA ejection fraction (LAEF) within the KT or dialysis group; changes over time did not differ between the 2 groups (all p > 0.25). At baseline and over 12 months, LA volumes and LAEF positively correlated with LV volumes and mass while LAEF positively correlated with LV function. Changes in LA volumes also positively correlated with NT-proBNP and systolic blood pressure (sBP) while LAEF negatively correlated with NT-proBNP. GDF-15 correlated with LA measurements at baseline but not in 12-month changes. hsCRP did not correlate with any LA measurements. Conclusions LA volumes and function as measured by CMR did not change significantly over 12 months post-KT. There were significant associations between LA and LV remodeling, NT-proBNP and sBP, suggesting common underlying pathophysiological mechanisms.