Chronic thromboembolic pulmonary hypertension treatment and sex: Systematic review and meta-analysis

Background and objectives: Chronic thromboembolic pulmonary hypertension (CTEPH) is a complication of pulmonary embolism and a major cause of chronic pulmonary hypertension leading to right heart failure and death. While pulmonary endarterectomy is the treatment of choice, some patients might benefit from medical therapy or balloon pulmonary angioplasty. Sex differences in outcomes of these therapies are not well characterized.

Material and methods: We conducted a systematic review and meta-analysis to investigate sex differences in outcomes of various therapies for CTEPH. We searched MEDLINE, PubMed, Embase, CINAHL and the Cochrane Library databases between January 1, 2010 and April 30, 2021, published in English. We pooled incidence estimates using random-effects meta-analyses. We evaluated heterogeneity using the I² statistic. We assessed publication bias using Begg's and Egger's tests. This study is registered in PROSPERO, CRD42021268504.

Results: A total of 19 studies met the eligibility criteria, but only 3 trials provided separate outcomes for women and men. Two studies evaluated the efficacy of BPA, and one study evaluated the efficacy of riociguat (129 patients). Overall, 57.3% of patients were women and 62.6% were in functional class III. Mean time of follow-up was 55.5 (SD 26.1) weeks. Women showed a significantly better response in cardiac index (mean difference [MD], 0.10L/min/m²; 95% confidence interval [CI], 0.04-0.16; I²=0%; P=0.001). Alternatively, the reduction of pulmonary vascular resistances was significantly higher for men than for women (MD, 161.17dynscm^-5; 95% CI, 67.99-254.35; I²=0%; P=0.0007).

Conclusions: Women and men might show different hemodynamic responses to riociguat or BPA for CTEPH.