[Clinical and hemodynamic evaluation of 6-week treatment of pulmonary hypertension in chronic obstructive lung diseases (COLD) with low dose of prazosin]

Abstract

The value of vasodilatatory treatment of pulmonary hypertension due to chronic obturative pulmonary disease (c.o.p.d.) is still controversial. However in patients with c.o.p.d. causal treatment as well as chronic domestic oxygen therapy have a wide range of limitations. Among vasodilator alpha-1 blockers show less vasodilator-related adverse effects, and as known from acute trials they exert a potent effect on pulmonary circulation in patients with pulmonary hypertension and c.o.p.d. Prazosin was studied in 11 patients (10 men, 1 women) aged 63 +/- 7 years with advanced c.o.p.d. (FVC 1.8 +/- 0.41, FEV1 0.99 +/- 0.55 l) (s) after their clinical stabilisation. In 4 of them prazosin was added to the maintenance dose of diuretics and digitalis. Subjective status, NYHA functional class, spirometric (FVC, FEV1) and gaseous (PaO2, PCO2) parameters, weight, systemic blood pressure, and heart rate were noted. During Swan-Ganz catheterization mean pulmonary artery pressure (MPAP), right ventricular end-diastolic pressure (RVEDP), pulmonary wedge pressure (PCWP), cardiac output (CO), systemic (SVR) and pulmonary (PVR) vascular resistance were measured. The acute trial with 1 mg prazosin taken orally was followed by 2- and 6-week of 3 mg prazosin treatment assessment. After a single dose of 1 mg prazosin there was a significant decrease in MPAP from 36 +/- 9 to 28 +/- 10 (p = 0.001) and 44% decrease in RVEDP (p = 0.05). CO increased by 16% (p = 0.01). The fall in PVR (30%, p = 0.01) exceeded that in SVR (17%, NS). No adverse effects were observed. During 2-week 3 mg a day prazosin therapy 2 patients were excluded following dyspnea and systemic hypotonia.(ABSTRACT TRUNCATED AT 250 WORDS)