Long-term outcome and effects of oral bosentan therapy in Taiwanese patients with advanced idiopathic pulmonary arterial hypertension

Echocardiography in Pulmonary Arterial Hypertension: Is It Time to Reconsider Its Prognostic Utility?

Pulmonary arterial hypertension (PAH) is characterized by an insult in the pulmonary vasculature, with subsequent right ventricular (RV) adaptation to the increased afterload that ultimately leads to RV failure. The awareness of the importance of RV function in PAH has increased considerably because right heart failure is the predominant cause of death in PAH patients. Given its wide availability and reduced cost, echocardiography is of paramount importance in the evaluation of the right heart in PAH. Several echocardiographic parameters have been shown to have prognostic implications in PAH; however, the role of echocardiography in the risk assessment of the PAH patient is limited under the current guidelines. This review discusses the echocardiographic evaluation of the RV in PAH and during therapy, and its prognostic implications, as well as the potential significant role of repeated echocardiographic assessment in the follow-up of patients with PAH.

Efficacy and Safety of Long-Term Oral Bosentan in Different Types of Pulmonary Arterial Hypertension: A Systematic Review and Meta-Analysis

OBJECTIVE

This systematic review and meta-analysis was conducted to identify if long-term bosentan is an effective and safe treatment for pulmonary arterial hypertension (PAH) regardless of type, including idiopathic PAH (IPAH), and PAH associated with congenital heart disease (APAH-CHD), connective tissue disease (APAH-CTD), and human immunodeficiency virus (APAH-HIV).

METHODS

All relevant observations were systematically searched by two independent investigators and obtained from three databases, including PubMed, EMBASE and the Cochrane Library, from the inception of each database to February 2020. Currently, long-term administration was defined as no less than 12 months. A random-effects or fixed-effects model was selected according to outcomes of the heterogeneity test for meta-analysis, where standardized mean difference (SMD) with 95% confidence intervals (CIs) was used for continuous outcomes, in addition to the estimated effect (ES; 95% CI) for the synthesized survival rate. Furthermore, subgroup analysis was applied to analyze the differences of efficacy and survivals in each type of PAH cohort.

RESULTS

Fifteen studies including a total of 659 subjects undergoing oral bosentan administration for at least 12 months were pooled in this quantitative review. Meta-analysis and subgroup analysis indicated that significant clinical benefits existed, including an improved 6-min walk distance (6MWD) and functional class (FC), in patients with APAH-CHD (6MWD: SMD 0.72, 95% CI 0.52-0.93, p < 0.0001; functional benefits: 50.4%, 95% CI 43.7-57.1%), APAH-HIV (6MWD: SMD 0.83, 95% CI 0.36-1.30, p = 0.001; functional benefits: 80.4%), and IPAH (SMD 0.54, 95% CI 0.28-0.80, p < 0.0001; functional benefits: 61.4%, 95% CI 54.2-68.5%), but a non-significant change in APAH-CTD (6MWD: SMD 0.18, 95% CI - 0.60 to 0.95, p = 0.656; functional benefits: 27.5%). Furthermore, among the hemodynamic parameters, long-term bosentan led to a significant decrease in mean pulmonary artery pressure (SMD - 0.86, p < 0.0001) in APAH-CTD, and a decrease in pulmonary vascular resistance (SMD - 0.65, p < 0.0001) and elevated oxygen saturation (SMD 0.30, p = 0.006) in APAH-CHD. Importantly, in all pooled studies, the overall survival indicated 1-, 2-, and 3-year survival rates of 94.3%, 88.8%, and 81.7%, respectively, in all-cause PAH, and subgroup analysis demonstrated a relative decreasing trend in patients with HIV, from a 2-year survival of 89.8% to a 3-year survival of 66.1%. Adverse drug reactions were relatively mild.

CONCLUSION

In this systematic review and meta-analysis, long-term administration of oral bosentan has been identified as a well-tolerated and effective agent in different types of PAH. In addition, we conclude that long-term oral bosentan should be considered for patients with CTD to achieve a satisfactory exercise capacity, and for those with APAH-HIV to improve survivals, where more attention on adverse events is required.

Bosentan for Treatment of Pediatric Idiopathic Pulmonary Arterial Hypertension: State-of-the-Art

Idiopathic pulmonary arterial hypertension (IPAH) is a complex disease associated with progressive deterioration. Targeted therapy for IPAH has improved in the last several decades. However, there remain many challenges to current treatment of children with IPAH, including poor prognosis and a median survival of 0.8 years. Endothelin-1 (ET-1) appears to be a key mediator in the pathogenesis of IPAH, with elevated concentrations in the plasma. Bosentan, an endothelin receptor antagonist, has been confirmed in Food and Drug Administration (FDA) to effectively treat IPAH when administered in recent studies. This review focuses on related studies and advance of bosentan in the treatment of IPAH in children.