Neurohormonal activation in patients with right ventricular failure from pulmonary hypertension: relation to hemodynamic variables and endothelin levels.

OBJECTIVES

This study sought to determine whether neurohormonal activation occurs in isolated right heart failure.

BACKGROUND

Neurohormonal activation appears to parallel the severity of left heart failure, but little is known about its role in right heart failure.

METHODS

We evaluated neurohormonal activation and endothelin levels in 21 patients with primary pulmonary hypertension at the time of right heart catheterization.

RESULTS

Plasma norepinephrine levels correlated significantly with pulmonary artery pressure (r = 0.66, p < 0.01), cardiac index (r = -0.56, p < 0.01) and pulmonary vascular resistance (r = 0.69, p < 0.001). Atrial natriuretic peptide levels were higher in the pulmonary artery than the right atrium and femoral artery and correlated closely with pulmonary artery oxygen saturation (r = -0.73, p < 0.0001). Plasma renin levels were not elevated. Endothelin levels were increased and correlated with right atrial pressure (r = 0.74, p < 0.0001) and pulmonary artery oxygen saturation (r = -0.070, p < 0.0004).

CONCLUSIONS

Neurohormonal activation occurs in patients with isolated right ventricular failure and inherently normal left ventricles and appears to be related to the overall severity of cardiopulmonary derangements. The elevation in endothelin levels is consistent with its release in response to pulmonary hypertension.