Exercise induced pulmonary hypertension in systemic sclerosis and treatment with ambrisentan: A prospective single center, open label, pilot study
Arthritis & Rheumatism, 07/10/2012
Saggar R et al. – Exercise hemodynamics and exercise capacity in patients with SSc–spectrum associated exercise PH improved over 24 weeks with exposure to ambrisentan (AMB). Placebo–controlled studies are needed to confirm whether this is a drug–related effect and to determine optimal therapeutic regimens for patients with exercise PH.Methods
- SSc–spectrum patients exercised using a supine lower extremity cycle ergometer at baseline and 24 weeks.
- All patients had normal hemodynamics at rest.
- Baseline ePH required: mean pulmonary artery pressure (mPA) > 30mmHg with maximum exercise and transpulmonary gradient (TPG) > 15mmHg.
- Patients were given either 5mg or 10mg of AMB once daily for 24 weeks.
- Primary endpoint was change in exercise pulmonary vascular resistance (PVR).
- Secondary endpoints included an improvement from baseline in 6MWD, health–related quality of life assessments, and cardiopulmonary hemodynamics.
- 11 of 12 enrolled patients completed study. At 24 weeks, mean exercise PVR (85.8 dyn/s/cm5, p=0.003) and mean 6MW (44.5 m, p=0.0007) improved.
- Improvements were also observed in: mean exercise CO (1.4 L/min, p=0.006), mean mPA (–4.1mmHg, p=0.02), total pulmonary resistance (TPR) (–93.0 dyn/s/cm5, p=0.0008).
- Three patients developed resting PAH during the 24 weeks.