1. Successful Transition From Phosphodiesterase-5 Inhibitors to Riociguat Without a Washout Period in Patients With Pulmonary Arterial Hypertension and Chronic Thromboembolic Pulmonary Hypertension: A Pilot Cohort Study
- Author
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Satoshi Akagi, Kazufumi Nakamura, Kentaro Ejiri, Kazuhiro Kuroda, Hiroshi Ito, and Toshihiro Sarashina
- Subjects
Adult ,Male ,Pulmonary and Respiratory Medicine ,Cardiac Catheterization ,medicine.medical_specialty ,Combination therapy ,Sildenafil ,Hemodynamics ,Pilot Projects ,030204 cardiovascular system & hematology ,Riociguat ,Cohort Studies ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Internal medicine ,medicine ,Humans ,030212 general & internal medicine ,Aged ,Monitoring, Physiologic ,Pulmonary Arterial Hypertension ,business.industry ,digestive, oral, and skin physiology ,Transitional Care ,Middle Aged ,Phosphodiesterase 5 Inhibitors ,medicine.disease ,Pulmonary hypertension ,Tadalafil ,Pyrimidines ,medicine.anatomical_structure ,chemistry ,cGMP-specific phosphodiesterase type 5 ,Chronic Disease ,Vascular resistance ,Cardiology ,Pyrazoles ,Female ,Pulmonary Embolism ,Cardiology and Cardiovascular Medicine ,business ,medicine.drug - Abstract
Background Transition to pulmonary arterial hypertension (PAH)-specific drugs is considered in patients with PAH and chronic thromboembolic pulmonary hypertension who do not respond to combination therapy or who experience side effects to the combination drugs. Riociguat directly stimulates soluble guanylate cyclase independently of nitric oxide. Therefore, transition from a phosphodiesterase type 5 inhibitor (PDE5i), which requires nitric oxide to exert its effects, to riociguat might be effective. The length of time of washout periods for transition is important because haemodynamic instability sometimes occurs during these periods or during transition with no washout period. Method We investigated the feasibility of transitioning from a PDE5i to riociguat without washout periods by monitoring haemodynamics under right heart catheterisation in six patients with PAH and one with chronic thromboembolic pulmonary hypertension who had already received dual- or triple-combination therapy. Results Reasons for transition were headache caused by a PDE5i in three patients, and an inadequate response to combination therapy in four. Transition was successful in all patients, with no haemodynamic instability observed. Pulmonary vascular resistance (from 797 ± 241 to 518 ± 230 dyne/s/cm–5) and systemic blood pressure (from 121 ± 13 to 100 ± 15 mmHg) were significantly reduced immediately after transition. There were no significant differences in the tricuspid regurgitation pressure gradient or systemic blood pressure during the post-transition and follow-up periods. Headaches caused by a PDE5i were diminished after transition to riociguat. Conclusions Transition from a PDE5i to riociguat without a washout period is safe. This transition may be a viable option for patients with headaches caused by a PDE5i, or who have an inadequate response to combination therapy that includes a PDE5i.
- Published
- 2020