704-3 Relation of Neurohormonal Activation to Functional Class in Patients with Primary or Precapillary Secondary Pulmonary Hypertension

Abstract

Intense neurohormonal activation has been demonstrated in patients with primary or precapillary secondary pulmonary hypertension (PH) but the relation of neurohormons to functional impairment is not well known. Plasma levels of atrial natriuretic peptide (ANP), aldosterone (ALD), renin activity (PRA), epinephrine (PE), norepinephrine (PNE) and endothelin (ET) were assessed from the antecubital vein in 12 patients with primary PH, 7 patients with precapillary secondary PH (2 connective tissue disease, 2 chronic thromboembolic, 3 closed atrial septal defect) and 10 control subjects. Twelve patients were in NYHA functional class II (PH-II) and 7 in class III/IV (PH-III/IV). Mean PA pressure (PAP), cardiac index (CI), pulmonary vascular resistance (PVR) and right atrial pressure were assessed by heart catheterization: PAP CI PVR RAP (mmHg) (l/minlm 2 ) (RU) (mmHg) PH-II 53 ± 13 2.4 ± 0.4 12 ± 3 3 ± 2 PH-III/IV 61 ± 9 2.0 ± 05 18 ± 6 11 ±5 P 0.17 0.07 0.009 0.0001 Neurohormons plasma levels in control subjects (C), PH-II and PH-III/IV patients were as follows: ANP ALD PRA PE PNE ET (pg/ml) (pg/ml) (ng/ml/h) (pg/ml) (pg/ml) (pg/ml) C 58 ± 18 110 ± 65 0.7 ± 0.4 33 ± 19 220 ± 101 1.7 ± 0.3 PH-II 167 ± 96 * 144 ± 102 15 ± 2.0 298 ± 263 * 420 ± 294 * 3.6 ± 1.4 * PH-III/IV 276 ± 153 *† 209 ± 270 3.2 ± 3.9 * 462 ± 524 * 820 ± 693 *† 8.4 ± 3.9 *° * p < 0.05 vs C° p < 0.001 vs PH-II † P < 0.09 vs PH-II Neurohormonal activation in primary or precapillary secondary PH is detectable also in patients without overt clinical and hemodynamic signs of right heart failure (PH-II). Neurohormonal activation seems to be progressive and is more severe in functional class III/IV patients. ET shows the best statistically significant relation with functional impairment.