[Clinical efficacy of prolonged therapy with NO on patients with pulmonary hypertension]

To determine the safety and clinical efficacy of prolonged NO administration in patients with pulmonary hypertension.

Clinical efficacy of prolonged treatment (28 days) with NO (20 ppm) in 17 patients with pulmonary hypertension was observed by chest X-ray film, ECG, Doppler echocardiography, analysis of arterial blood gases and the other laboratory investigations.

After prolonged treatment with NO, regurgitation velocity and peak pressure gradient across tricuspid valves during systole reduced by 11.8% and 22.6%, respectively (P < 0.0001). Ejection fraction of right ventricle, stroke volume and cardiac output of left ventricle, partial oxygen pressure and oxygen saturation of arterial blood increased by 29.9%, 60.3%, 37.8%, 21.7% and 3.8% (all statistics; P < 0.0001), respectively. The class of heart function by New York Heart Association (NYHA) was improved dramatically (P < 0.01). Heart rate also reduced from 96 +/- 12 bpm to 83 +/- 10 bpm (P < 0.0001). But systemic artery pressure and the concentration of blood methemoglobin which reflected NO toxicity did not change obviously (P > 0.05).

Clinical efficacy of prolonged treatment with NO is satisfied in patients with pulmonary hypertension. Significant clinical side effects and toxicities are not seen during prolonged treatment with NO.