Exercise capacity in idiopathic pulmonary fibrosis: The effect of pulmonary hypertension


    loading  Checking for direct PDF access through Ovid

Abstract

Background and objective:Increased pulmonary arterial pressure (PAP) usually coexists with impaired lung function in IPF. Data on the effect of pulmonary hypertension (PH) on cardiopulmonary responses during exercise in IPF patients is very limited. We sought to investigate the impact of PH on exercise capacity and the correlation between systolic PAP (sPAP) and pulmonary function testing, as well as cardiopulmonary exercise parameters, in patients with IPF and PH.Methods:Eighty-one consecutive patients with IPF, who were evaluated over a 6-year period, were retrospectively studied. Patients underwent pulmonary function testing, Doppler echocardiography and maximal cardiopulmonary exercise testing. PH was defined as sPAP > 35 mm Hg.Results:PH was diagnosed in 57% of the patients. Categorization of patients according to severity of PH indicated a significant reduction in maximum work rate, peak O2 uptake, anaerobic threshold and peak O2 pulse in those with sPAP > 50 mm Hg. In IPF patients with PH, estimated sPAP correlated with peak O2 uptake, anaerobic threshold, peak O2 pulse and end-tidal CO2 at anaerobic threshold, while the strongest correlation was between sPAP and ventilatory equivalent for CO2 at anaerobic threshold (r = 0.611, P < 0.001). There were no differences in pulmonary function or exercise parameters indicative of lung volume reduction, across the patient categories, and none of these parameters correlated with sPAP.Conclusions:PH has a negative impact on exercise capacity in IPF patients. In IPF patients with PH, resting sPAP correlated with exercise parameters indicative of gas exchange and circulatory impairment, but not with defective lung mechanics.Pulmonary hypertension (PH) results in exercise limitation in patients with IPF. Although resting pulmonary function measurements are minimally informative regarding the presence and impact of PH, exercise parameters indicative of circulatory impairment correlate significantly with systolic pulmonary arterial pressure in patients with IPF and PH.

    loading  Loading Related Articles