EFFECTS OF SINGLE INTRAVENOUS ADMINISTRATION OF URAPIDIL AND DILTIAZEM IN PATIENTS WITH NONFIXED PULMONARY-HYPERTENSION SECONDARY TO CHRONIC OBSTRUCTIVE LUNG-DISEASE

In patients with chronic obstructive lung disease (COLD), pulmonary hypertension (PH) often develops in addition over the course of years. In this study, the acute effects of urapidil and diltiazem in patients with mild PH secondary to COLD were investigated. Eighteen male and 2 female patients, aged 42-78 years, received in randomized, single-blind fashion single intravenous (i.v.) doses of either urapidil (35-50 mg, n = 10) or diltiazem (25 mg, n = 10). Mean pulmonary artery pressure (MPAP), pulmonary wedge pressure (PWP), mean arterial blood pressure (BP) (MAP), and arterial and central venous blood gases were determined at rest and during exercise (starting with 25 W with increases in 25-W steps) before and after drug administration. Urapidil caused a significant reduction in MPAP (from 19 +/- 7 to 15 +/- 4 mm Hg, p < 0.01), PWP (from 9 +/- 3 to 7 +/- 2 mm Hg, p < 0.05), but not significantly in MAP at rest, whereas with diltiazem only MAP was decreased (from 103 +/- 14 to 98 +/- 12 mm Hg, p < 0.05) and MPAP and PWP were not significantly increased. At the highest comparable workload, urapidil caused a significant decrease in MPAP (from 42 +/- 10 to 29 +/- 8 mm Hg, p < 0.001), PWP (from 18 +/- 3 to 12 +/- 4 mm Hg, p < 0.01) and MAP (from 127 +/12 to 112 +/- 12, p < 0.01); diltiazem reduced MAP (from 11 6 +/- 11 to 111 +/- 11 mm Hg, p < 0.0 1) only, and MPAP and PWP increased in 8 of 10 patients, although not significantly. Arterial and central venous blood gases remained unchanged or showed negligible changes with both medications. A single dose of urapidil reduced after-load of the fight ventricle in our patient population. Diltiazem in the dosage administered reduced only MAP, whereas MPAP and PWP tended to increase.