Nifedipine Reduces Pulmonary Pressure and Vascular Tone during Short- but Not Long-term Treatment of Pulmonary Hypertension in Patients with Chronic Obstructive Pulmonary Disease

Publisher Website
Google Scholar
Abstract
We evaluated in patients suffering from COPD-related pulmonary hypertension whether nifedipine therapy lowers acutely and chronically pulmonary vascular pressure and resistance and whether pulmonary vascular tone were determined on the pulmonary driving pressure/flow curve, which was generated by upright exercise. Fifteen patients with COPD and mean pulmonary pressure .gtoreq. 20 mm Hg were studied at control (Week 0) and after 1 wk of nifedipine treatment (180 mg daily, Week 1). It was possible to pursue the same nifedipine daily dosage for 2 months in 10 patients, who were re-evaluated after 8 wk of treatment and after nifedipine withdrawal the following week. At Week 1, mean pulmonary transmural pressure was reduced (32.8 .+-. 4.1 versus 27.3 .+-. 2.8 mm Hg, mean .+-. SE, p < 0.05) via active pulmonary vasodilation because the pulmonary driving pressure/flow curve was shifted right and downward. Both mean transmural pulmonary pressure lowering effect and active pulmonary vasodilatation regressed during long-term nifedipine treatment. Oxygen reduced pulmonary transmural pressure (32.8 .+-. 4.1 versus 28.6 .+-. 2.9 mm Hg, p < 0.05, Week 0); however, this effect always disappeared during nifedipine treatment. We conclude that nifedipine should not be used as long-term treatment for COPD-related pulmonary hypertension and that nifedipine inhibits the oxygen capability to reduce pulmonary pressure.