Atrial function, atrial volume and cardiovascular clinical outcomes in patients with end-stage renal disease - A study of cardiac computed tomography

Abstract

Background: Patients with chronic kidney disease (CKD) have an increased risk of cardiovascular events. Previous studies using 2-dimensional echocardiography show that left atrial end-diastolic volume (LAEDV) predicts cardiovascular outcomes and mortality in patients with CKD. However, contrast-enhanced cardiac CT may offers a more precise measure of atrial dimensions and function than 2-dimensional echocardiography and may provide improved predictionof patient outcome.

Aim: The aim of the present study was to examine the association of LAEDV and left atrial ejection fraction (LAEF) assessed by CT with left ventricle end-diastolic volume (LVEDV), left ventricular mass, left ventricular ejection fraction and N-terminal plasma-pro-brain natriuretic peptide (NT-PRO-BNP). Furthermore, we examined LAEDV and LAEF as predictors of major adverse cardiac events (MACE) and mortality.

Methods: Kidney transplant candidates (n = 117) underwent contrast-enhanced CT screening for coronary artery disease as part of the work-up prior to kidney transplantation before being accepted on the transplantation waiting list. Left atrial (LA) and left ventricular (LV) volume and function were determined by cardiac CT. MACE and mortality data were extracted from the Western Denmark Heart Registry, a review of patient records and patient interviews.

Results: Baseline patient characteristics did not differ between LAEDV tertiles. LAEDV was positively associated with measures of LV function - both LVEDV (β = 0.36, p < 0.05) and LV mass (β = 0.30, p < 0.05). LAEF was not associated with measures of LV function. LAEDV was positively and LAEF negatively associated with NT-PRO-BNP (LAEDV: β = 10.28, p < 0.05. LAEF: β = -0.06, p < 0.05). During a median follow-up of 3.7-years, 19 (16.2%) patients died and 19 (16.2%) patients suffered MACE. MACE and survival analysis showed no relation to LAEDV or LAEF.

Conclusions: Using contrast-enhanced CT, we demonstrated a correlation between atrial and ventricular functional parameters. However, we found no association with either LAEF or LAEDV or MACE and mortality in this cohort of kidney transplant candidates.

Keywords: Cardiac computed tomography angiography; Chronic kidney disease; Left atrial function; Left atrial volume; Major adverse cardiac events.