Left atrial volume and adverse cardiovascular outcomes in unselected patients with and without CKD.

BACKGROUND AND OBJECTIVES: Patients with CKD have increased cardiovascular morbidity and mortality. This study investigated the prognostic value of common clinical echocardiographic parameters.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: There were 289 unselected consecutive patients who had a transthoracic echocardiogram between January and June 2003. Patients with stage 3 or 4 CKD (n=49) were compared with those with eGFR≥60 ml/min per 1.73 m(2), n=240). Left ventricular volume, ejection fraction and mass, left atrial volume, and function parameters were measured. The primary endpoint, determined a priori, was a composite of cardiac death, myocardial infarction, and congestive cardiac failure.

RESULTS: Patients were followed for a median 5.6 years. The incidence of the primary endpoint was higher in patients with CKD (29% versus 12%, P=0.001), who were older and had a higher prevalence of hypertension and ischemic heart disease. Indexed left ventricular mass (LVMI) and left atrial volume (LAVI) were higher in patients with CKD. Furthermore, patients with LAVI>32 ml/m(2) had significantly lower event-free survival than patients with normal (<28 ml/m(2)) or mildly dilated LAVI (28-32 ml/m(2)) (P<0.001). Multivariate analysis showed that age (odds ratio [OR], 1.19; 95% confidence interval [95% CI], 1.08 to 1.31; P=0.001) and LVMI (OR, 3.66; 95% CI, 2.47 to 5.41; P<0.001) were independently associated with LAVI>32 ml/m(2). Multivariate Cox regression analysis demonstrated that CKD (hazard ratio [HR], 1.13; 95% CI, 1.01 to 1.26; P=0.04), hypertension (HR, 2.18; 95% CI, 1.05 to 4.54; P=0.04), and a larger LAVI (HR, 1.35; 95% CI, 1.02 to 1.77; P=0.04) were independent predictors of the primary endpoint.

CONCLUSIONS: Patients with CKD were at higher risk for cardiovascular events. LAVI was significantly larger in the CKD group and was a predictor of adverse cardiac events.