ABSTRACT
Pulmonary hypertension [PH] is an important cause of heart failure in chronic obstructive pulmonary disease [COPD]. The pro brain natriuretic peptide N-terminal [NT-proBNP] has been suggested as a noninvasive marker to evaluate ventricular function. However, there is no evidence to support the use of NT-proBNP in monitoring the benefits of vasodilators in COPD induced PH. Thus, we used NT-proBNP as a biomarker to evaluate the effect of oral vasodilators on cardiac function in COPD-induced PH. Forty clinically-stable PH patients were enrolled with history of COPD, normal left ventricular ejection-fraction [LVEF], right ventricular systolic pressure [RVSP] > 45 mmHg and baseline blood NT-proBNP levels >100 pg/mL. Patients were randomized into two groups, one group received sildenafil and second group were given amlodipine for two weeks. NT- proBNP and systolic pulmonary arterial pressure [systolic PA-pressure] were measured at the beginning and the end of study. Mean NT-proBNP level in the first group was 1297 +/- 912 pg/mL before therapy and 554 +/- 5 pg/mL after two weeks drug therapy, respectively. Similarly, in second group NT- proBNP level was 1657 +/- 989 pg/mL and 646 +/- 5 pg/mL before and after treatment. Amlodipine or sildenafil significantly reduced NT-proBNP levels in COPD-induced PH patients [p < 0.05]. Our study shows that amlodipine and sildenafil have a similar effect on NT-proBNP levels. In both groups NT- proBNP levels were significantly reduced after treatment. Therefore, our findings support the potential benefits of treatment with vasodilators in COPD induced PH