Abstract
Background: Riociguat is a soluble guanylate cyclase stimulator approved for pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTPEH).
Objectives: Aim of this study was to evaluate the change of right heart size and function assessed by echocardiography during long-term treatment with riociguat.
Methods: We assessed patients who started riociguat treatment within the trials PATENT, PATENTplus, EAS, CHEST and continued for 3-12 months. Echocardiography, 6-minute walking distance (6MWD) and further clinical parameters were analyzed at baseline, after 3, 6 and 12 months. Right heart catheterization was performed at baseline and after 3 months. For missing data we performed the last and baseline observation carried forward (LOCF, BOCF) method.
Results: Thirty-nine patients (21 PAH, 18 CTEPH, 56.4% treatment-naïve) were included. Mean right ventricular (RV) area significantly decreased after 3 (-2.1±3.9cm2, equals 7.4±15.3%, p<0.01), 6 (-4.2±3.2cm2, equals 16.1±11.5%, p<0.001) and 12 months (-5.9±4.6cm2, equals 22.1±14.2%, p<0.001) compared to baseline. Right atrial area significantly decreased after 12 months (-3.5±4.1cm2, equals 16.8±19.2%, p<0.001). TAPSE significantly improved after 6 (+2±4.7, equals 12±25.8%, p=0.03) and 12 months (+3.6±5.4, equals 21.0±29.6%, p<0.01). RV wall thickness and 6MWD significantly improved after 3, 6 and 12 months (p<0.05). Invasive hemodynamics significantly improved after 3 months. LOCF and BOCF showed similar significance and lower effect sizes.
Conclusion: Treatment with riociguat significantly reduced right heart size and improved RV function in PAH and CTEPH. Further prospective studies are needed.
- Copyright ©ERS 2015
