Neurohormonal Activation and Exercise Function in Patients With Severe Heart Failure and Patients With Left Ventricular Assist System: A Comparative Study

Abstract

The aim of this study was to evaluate the effects of implantation of a left ventricular assist system (LVAS) on the neurohormonal status, exercise capacity and symptomatic state in patients with severe congestive heart failure (CHF).Severe CHF is characterized by decreased exercise tolerance and activation of several neurohormonal systems.Parameters of neurohormonal activation and exercise capacity in patients with LVAS (n = 7) were compared with those in groups of New York Heart Association (NYHA) class 3 (n = 121) and class 4 (n = 81) patients. Plasma levels of norepinephrine (NE), plasma renin activity (PRA), and atrial natriuretic peptide (ANP) and maximal and submaximal exercise capacities were measured monthly in LVAS patients and compared with results in CHF patients.Plasma NE and PRA levels were significantly lower in LVAS patients than in NYHA class 4 patients, and plasma ANP levels in LVAS patients were significantly lower than those in NYHA class 3 and 4 patients. The distance walked during submaximal exercise testing and peak oxygen consumption during maximal exercise testing were similar for the LVAS and NYHA class 3 patients. The class 4 patients were unable to exercise.We conclude that the LVAS lessens the neurohormonal activation and exercise intolerance characteristic of the CHF state and that the exercise capacity early after LVAS (< 4 months) is similar to that observed in NYHA class 3 patients.