Borderline pulmonary arterial pressure is associated with decreased exercise capacity in scleroderma.
BACKGROUND
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.


OBJECTIVE
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.


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 Vo(2) (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 Vo(2); 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).
Kovacs
Gabor
G
Department of Pulmonology, Medical University Graz, Graz, Austria.
Maier
Robert
R
Aberer
Elisabeth
E
Brodmann
Marianne
M
Scheidl
Stefan
S
Tröster
Natascha
N
Hesse
Christian
C
Salmhofer
Wolfgang
W
Graninger
Winfried
W
Gruenig
Ekkehard
E
Rubin
Lewis J
LJ
Olschewski
Horst
H
D001794:Blood Pressure; D006328:Cardiac Catheterization; D015444:Exercise; D005080:Exercise Test / Q000379:methods / Q000706:statistics & numerical data; D017079:Exercise Tolerance; D006801:Humans; D008875:Middle Aged; D012146:Rest; D012595:Scleroderma, Systemic / Q000503:physiopathology*; D014655:Vascular Resistance; D016138:Walking