Efficacy and safety of tetramethylpyrazine phosphate on pulmonary hypertension: study protocol for a randomized controlled study

Introduction Tetramethylpyrazine (TMP), one of the active ingredients from the traditional Chinese herbal medicine Rhizoma Chuanxiong (Chuanxiong), has been clinically used for the prevention and treatment on cardiovascular diseases. The benefits of TMP are largely attributed to its anti-oxidize and vasodilative activities. However, the efficacy of TMP in the treatment of pulmonary hypertension(PH) is unknown, in this study, we hypothesized that TMP treatment has a therapeutic effect on PH patients.