RT Journal Article
SR Electronic
T1 Changes in exercise haemodynamics during treatment in pulmonary arterial hypertension
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 393
OP 398
DO 10.1183/09031936.00009008
VO 32
IS 2
A1 S. Provencher
A1 P. Hervé
A1 O. Sitbon
A1 M. Humbert
A1 G. Simonneau
A1 D. Chemla
YR 2008
UL http://erj.ersjournals.com/content/32/2/393.abstract
AB Improvement in exercise capacity may not be associated with significant changes in resting pulmonary haemodynamics. The present prospective study documented the relationships between improvement in 6-min walking distance (6MWD) and changes in resting and exercise pulmonary haemodynamics after treatment in patients with idiopathic pulmonary arterial hypertension (IPAH). A total of 42 IPAH patients underwent supine submaximal exercise haemodynamic assessments at baseline and after 5±2 months of therapy. The 6MWD, the corresponding chronotropic response (peak minus resting heart rate), and resting and exercise haemodynamic variables were analysed. The isoflow was defined as the lowest of the pre- and post-treatment peak cardiac index (CI). The extrapolated isoflow mean pulmonary artery pressure (P̄pa) was used to characterise changes in P̄pa–CI regression lines following treatment. Patients were given bosentan (n = 28), epoprostenol (n = 12) or both. The 6MWD increased significantly, from 399±88 to 442±86 m. On univariate analysis, changes in 6MWD correlated with changes in isoflow P̄pa, chronotropic response, resting haemodynamics (CI, pulmonary vascular resistance and mixed venous oxygen saturation) and exercise haemodynamics (peak CI). On multivariate analysis, only changes in isoflow P̄pa and chronotropic response were independently associated with changes in 6MWD. Improvement in exercise tolerance with chronic therapy is independently related to improvement in pulmonary haemodynamics measured in exercise but not in resting conditions.