Effectiveness of Bosentan in the Treatment of Chronic Thromboembolic Pulmonary Hypertension: A Systematic Review of Randomized and Nonrandomized Trials

Gröne J, Hamulyak K.  Effectiveness of Bosentan in the Treatment of Chronic Thromboembolic Pulmonary Hypertension:  A Systematic Review of Ramdomized and Nonrandomized Trials.  Journal of Coagulation Disorders, July 2010; 2(2):  81-88

REVIEW ARTICLE


Johanna Gröne¹ and Karly Hamulyák²

Affiliations: ¹Faculty of Health, Medicine & Life Sciences, Maastricht University, Maastricht, the Netherlands and ²Department of Haematology, Maastricht University Medical Centre, Maastricht, the Netherlands


ABSTRACT

BACKGROUND
There is a lack of approved medical treatment options in patients with chronic thromboembolic pulmonary hypertension (CTEPH) who are not eligible for pulmonary endarterectomy.

OBJECTIVE
To assess the effectiveness of bosentan in improving pulmonary hemodynamics and functional parameters in adults diagnosed with CTEPH.

METHODS
A systematic review of articles identified in PubMed, MEDLINE, Embase, and Cochrane databases with the search terms bosentan and chronic thromboembolic pulmonary hypertension was done. Randomized and nonrandomized trials that compared bosentan to placebo or standard therapy were included. Studies were assessed for methodological quality one period only please.

RESULTS
Only two studies met the predefined inclusion criteria, one randomized controlled trial (RCT, n=157) and one nonrandomized trial (n=34). The RCT found a significant lowering of the pulmonary vascular resistance in the bosentan group after 16 weeks, which did not translate into an improved exercise capacity. The nonrandomized trial showed a significant improvement in 6-minute walking distance when patients receiving bosentan in addition to standard therapy were compared with patients receiving only standard therapy after one year one period only please.

LIMITATIONS
The studies either did not include an adequate number of patients or did not have a sufficiently long follow-up to permit drawing sound conclusions. At review level, there is threat of publication bias, as only published studies were included.

CONCLUSION
The evidence for beneficial effects of bosentan in studies to date is insufficient to clearly establish its role as medical therapy for CTEPH. It is therefore necessary to conduct large randomized clinical trials that follow patients for a minimum of one year to clarify the efficacy of bosentan.

Keywords: chronic thromboembolic pulmonary hypertension, bosentan, systematic review

Correspondence: Johanna Gröne, Onderwijsinstituut FHML (opleiding geneeskunde), Maastricht University, PO Box 616, 6200 MD Maastricht, The Netherlands. Tel: +31 620 418 524; e-mail: j.groene@student.maastrichtuniversity.nl