Usefulness of left atrial strain to predict end stage renal failure in patients with chronic kidney disease

Left atrial (LA) enlargement predicts adverse cardiovascular events in patients with chronic kidney disease (CKD). The aim of our study was to evaluate the value of LA reservoir strain, a novel measure of LA function, as a prognostic marker for adverse renal outcomes. A total of 280 patients (65.8 ± 12.2years, 63% male) with stable Stage 3 and 4 CKD without prior cardiac history were evaluated with transthoracic echocardiography and prospectively followed for up to 5 years. The primary end point was progressive renal failure, which was the composite of death from renal cause, end-stage renal failure and/or doubling of serum creatinine. Over a mean follow up of 3.9 ± 2.7years, 56 patients reached the composite endpoint. By log rank test, older age, lower baseline eGFR, anemia, diabetes mellitus, higher urinary albumin/creatinine ratio, number of antihypertensive medications, higher indexed left ventricular mass, larger LA volumes, and impaired LA reservoir strain were significant predictors of the composite outcome (p <0.01 for all). Multi-variable Cox regression analysis found LA reservoir strain, eGFR, number of antihypertensive medications and urinary albumin/creatinine ratio were independent predictors for progressive renal failure (p <0.01 for all). Impaired LA reservoir strain was associated with a 2.5-fold higher risk of the composite outcome (HR 2.51, 95% CI 1.19 to 5.30, p = 0.02) and was the only echocardiographic parameter that predicted progressive renal failure independent of established clinical risk factors for end-stage renal failure. Its utility requires validation in high risk CKD patients with cardiac disease.