Akihiro Hirashiki1, Shiro Adachi2, Yoshihisa Nakano2, Yuji Kono3, Shuzo Shimazu2, Shinya Shimizu2, Ryota Morimoto2, Takahiro Okumura2, Kyosuke Takeshita2, Sumio Yamada3, Toyoaki Murohara2, Takahisa Kondo4. 1. Department of Advanced Medicine in Cardiopulmonary Disease, Nagoya University Graduate School of Medicine, Nagoya 466-8560, Japan. 2. Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya 466-8560, Japan. 3. Department of Rehabilitation Science, Nagoya University Graduate School of Medicine, Nagoya 461-8673, Japan. 4. Department of Advanced Medicine in Cardiopulmonary Disease, Nagoya University Graduate School of Medicine, Nagoya 466-8560, Japan. Electronic address: takahisa@med.nagoya-u.ac.jp.
Abstract
AIMS: The 6-min walking distance is often used for assessing the exercise capacity under the treatment with an endothelin receptor antagonist (ERA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH). The cardiopulmonary exercise testing (CPX) was reported to be more useful for the patients with pulmonary arterial hypertension (PAH), however, few reports exist in patients with inoperable CTEPH. The aim of this study was to investigate the effects of an oral dual ERA, bosentan, on exercise capacity using CPX in patients with PAH and inoperable CTEPH. MAIN METHODS: This study included all patients diagnosed with 17 PAH and 12 CTEPH in the World Health Organization functional classes II-IV who started treatment with bosentan therapy. They underwent CPX, which was performed before bosentan therapy and at 3 to 6 months of the treatment. KEY FINDINGS: In PAH patients, peak VO2 significantly increased after the bosentan treatment (p=0.009). On the other hand, in CTEPH patients, there were no significant differences in the peak VO2. However, the peak PETCO2 was significantly increased from 23.9±5.2 mm Hg at baseline to 29.3±10.7 mm Hg after the bosentan treatment (p=0.040). In addition, peak heart rate during exercise tended to decrease after the bosentan therapy (p=0.089). SIGNIFICANCE: Bosentan therapy improved peak PETCO2 but not peak VO2 in patients with inoperable CTEPH. These findings demonstrated that CPX is useful for assessing the exercise capacity of patients with PAH and inoperable CTEPH under the treatment with an ERA.
AIMS: The 6-min walking distance is often used for assessing the exercise capacity under the treatment with an endothelin receptor antagonist (ERA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH). The cardiopulmonary exercise testing (CPX) was reported to be more useful for the patients with pulmonary arterial hypertension (PAH), however, few reports exist in patients with inoperable CTEPH. The aim of this study was to investigate the effects of an oral dual ERA, bosentan, on exercise capacity using CPX in patients with PAH and inoperable CTEPH. MAIN METHODS: This study included all patients diagnosed with 17 PAH and 12 CTEPH in the World Health Organization functional classes II-IV who started treatment with bosentan therapy. They underwent CPX, which was performed before bosentan therapy and at 3 to 6 months of the treatment. KEY FINDINGS: In PAH patients, peak VO2 significantly increased after the bosentan treatment (p=0.009). On the other hand, in CTEPHpatients, there were no significant differences in the peak VO2. However, the peak PETCO2 was significantly increased from 23.9±5.2 mm Hg at baseline to 29.3±10.7 mm Hg after the bosentan treatment (p=0.040). In addition, peak heart rate during exercise tended to decrease after the bosentan therapy (p=0.089). SIGNIFICANCE: Bosentan therapy improved peak PETCO2 but not peak VO2 in patients with inoperable CTEPH. These findings demonstrated that CPX is useful for assessing the exercise capacity of patients with PAH and inoperable CTEPH under the treatment with an ERA.