Abstract

Objective Left atrial volume (LAV) is a powerful predictor of outcome in patients with chronic heart failure (CHF) independently of symptomatic status, age and left ventricular (LV) function. It is unknown whether LAV provides independent and incremental information compared with exercise tolerance parameters.

Methods 273 CHF patients (62±9 years; 13% female) prospectively underwent to echocardiography and exercise testing with maximal oxygen consumption (VO2). The primary end point was composite and included cardiac death, hospitalization for worsening heart failure or cardiac transplatation.

Results At Cox proportional hazard analysis, LAV normalized for body surface area (LAV/BSA) was strongly associated with mortality (HR 1.027 (95% IC 1.018 10.4; p<0.0001). The predictive value of LAV/BSA was independent of VO2 and LV ejection fraction (EF) (HR 1.015 (1.005 1.026) p=0.004; HR 0.95 (0.91 0.99) p=0.01; HR 0.89 (0.81 0.97) p=0.009 for LAV/BSA, EF and VO2 respectively). ROC analysis identified the best cut-off values for the prediction of the end point. LAV/BSA > 63 mL, EF <30% and VO2 < 16 mL/Kg/min were considered to be risk factors. Patients with 3 risk factors had a hazard ratio of 38 (95% IC 11 129) compared with patients with no risk factors.

Conclusion LAV provides powerful prognostic information incrementally and independently of VO2. LAV, EF and VO2 can be used to build a risk prediction model, which can be used clinically.