This Article Full Text Full Text (PDF) Online Supplement All Versions of this Article: 200904-0563OCv1 180/9/881    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Google Scholar Articles by Kovacs, G. Articles by Olschewski, H. PubMed PubMed Citation Articles by Kovacs, G. Articles by Olschewski, H.

Borderline Pulmonary Arterial Pressure Is Associated with Decreased Exercise Capacity in Scleroderma

¹ Departments of Pulmonology, ² Cardiology, ³ Dermatology, ⁴ Angiology, and ⁵ Rheumatology, Medical University Graz, Graz, Austria; ⁶ Department of Cardiology, University of Heidelberg, Heidelberg, Germany; and ⁷ University of California San Diego Medical Center, La Jolla, California

Correspondence and requests for reprints should be addressed to Horst Olschewski, M.D., Medical University Graz, Department of Pulmonology Austria 8036, Graz, Auenbruggerplatz 20. E-mail: horst.olschewski{at}meduni-graz.at

Rationale: Pulmonary arterial hypertension is associated with impaired exercise capacity and decreased survival in patients with scleroderma. Randomized controlled studies showed significant benefit of targeted therapies in patients with a resting mean pulmonary arterial pressure (MPAP) greater than 25 mm Hg. The clinical relevance of pulmonary arterial pressure values in the upper normal range is unknown.

Objectives: To examine the clinical relevance of pulmonary arterial pressure in scleroderma patients.

Methods: After a noninvasive screening program, 29 patients with systemic sclerosis without significant lung fibrosis and without known pulmonary arterial hypertension underwent right heart catheterization and simultaneous cardiopulmonary exercise test. A six-minute walk distance (6MWD) was determined within 48 hours.

Measurements and Main Results: A resting MPAP above the median (17 mm Hg) was associated with decreased 6MWD (396 ± 71 vs. 488 ± 76 m; P < 0.005) and peak VO₂ (76 ± 11% vs. 90 ± 24%; P = 0.05). Resting pulmonary vascular resistance was inversely correlated with 6MWD (r = 0.45; P < 0.05). At 25 and 50W, MPAP above the median (23 and 28 mm Hg) was associated with decreased 6MWD (P < 0.005; P < 0.0005). At peak exercise, MPAP showed no association with 6MWD or peak VO₂; however, cardiac index was positively (r = 0.45; P < 0.05) and pulmonary vascular resistance was negatively correlated with 6MWD (r = –0.38; P < 0.05).

Conclusions: MPAP and resistance in the upper normal range at rest and moderate exercise are associated with decreased exercise capacity and may indicate early pulmonary vasculopathy in patients with systemic sclerosis. Investigations on the prognostic and therapeutic implications of such borderline findings are warranted.

Clinical trial registered with http://www.clinicaltrials.gov (NCT00609349).

Key Words: exercise capacity • connective tissue disease • pulmonary arterial hypertension • pulmonary arterial pressure increase

AT A GLANCE COMMENTARY Scientific Knowledge on the Subject The presence of manifest pulmonary hypertension is associated with worse prognosis in systemic sclerosis. What This Study Adds to the Field Borderline elevation of mean pulmonary arterial pressure at rest and during exercise may represent early pulmonary vasculopathy and is associated with decreased exercise capacity in patients with systemic sclerosis.