It was shown recently that a thirty day doxazosin therapy, that was undertaken to prove alpha1-adrenergic hypothesis for pulmonary hypertension, resulted in a significant improvement of pulmonary hemodynamics in patients with hypoxic pulmonary hypertension (HPH) due to COPD.
Aim of the study: The objective of this study was to learn if 12 months long therapy with 2 mg of doxazosin daily (dosage effective in recent research) may result in persistent hemodynamical and clinical benefits.
Material and methods: To this end, baseline and after 1 year results of echocardiography, symptom-limited maximal exercise test, and arterial blood gaseous analysis were evaluated at baseline and after 12-month study in 32 patients with HPH randomized either to doxazosin treated group (16 patients, aged 60.2 +/- 12 years, or to control group (16 patients, aging 60.5 +/- 4 years). At baseline doxazosin treated COPD patients had less advanced disease than COPD control patients (FVC 2.4 +/- 0.7 vs 1.3 +/- 0.31, p<0,001 and FEV1 1.6 +/- 0.6 vs 0.7 +/- 0.31, p<0,001).
Results: This study showed that results of tricuspid gradient, acceleration time, right ventricular enddiastolic diameter, left ventricular enddiastolic diameter and left ventricular ejection fraction did not differ significantly in both groups between baseline and 1-year assessment. The number of METs achieved during exercise test and results of PaO2 and PaCO2 did not change significantly in both groups either.
Conclusion: The study indicates lack of hemodynamical and clinical improvement during a 1-year doxazosin therapy in patients with HPH due to COPD.