Pulmonary artery hypertension in adult patients with symptomatic valvular aortic stenosis

Abstract

Pulmonary hypertension (PH) has been reported in patients with valvular aortic stenosis (AS) and has been found to be associated with a more severe clinical picture and a poor prognosis after aortic valve replacement. The aim of this study was to assess the prevalence of PH in adult patients with symptomatic AS undergoing cardiac catheterization, and to evaluate the relation between pulmonary artery (PA) systolic pressure and hemodynamic and clinical variables to further clarify the pathogenetic mechanisms. We assessed right-sided heart hemodynamics during cardiac catheterization in 388 patients with symptomatic isolated or predominant AS. PA systolic pressure between 31 and 50 mm Hg was used to define mild to moderate PH, whereas PA systolic pressure >50 mm Hg was used to define severe PH. PA systolic pressure showed no significant difference according to age and sex, although it was significantly higher in patients in New York Heart Association functional classes III and IV and in patients with coexistent systemic hypertension than in the others. PH was absent in 136 patients (35%, group 1), mild to moderate in 196 patients (50%, group 2), and severe in 58 patients (15%, group 3). Only the prevalence of overt heart failure was significantly higher in group 3 patients. AS severity was similar among the 3 groups, and PA systolic pressure showed no relation to aortic valve area in the entire population. Also, a poor correlation was found between PA pressure and left ventricular (LV) ejection fraction (r = -0.28), with several patients having moderate or severe PH despite a preserved LV systolic function. PA systolic pressure significantly correlated with LV end-diastolic pressure (r = 0.50) and with PA wedge pressure (r = 0.84). Furthermore, transpulmonary pressure gradient, an index of resistance across the pulmonary vascular bed (obtained as the difference between PA mean and PA wedge pressure), was significantly higher in patients with PH, especially in those with a marked increase in PA systolic pressure, suggesting a reactive component of PH.