Pulmonary artery enlargement in schistosomiasis associated pulmonary arterial hypertension

BACKGROUND Schistosomiasis associated pulmonary arterial hypertension (Sch-PAH) might represent the most prevalent form of PAH worldwide. In Sch-PAH, the presence of aneurismal dilation of the pulmonary artery has been described, although it is still a matter of debate whether on average the pulmonary artery is more enlarged in Sc-PAH than IPAH. METHODS We retrospectively evaluated patients with IPAH (n = 25) and Sch-PAH (n = 22) who underwent computed tomography pulmonary angiogram and right heart catheterization. RESULTS Sch-PAH patients were older and presented less severe hemodynamic profiles. Main pulmonary artery diameter (MPAD) was greater in Sch-PAH than IPAH (4.5 ± 1.8 vs 3.7 ± 1.1 cm, p = 0.018). For the same level of mean pulmonary artery pressure, the MPAD in Sch-PAH was 0.89 cm larger than in IPAH (Covariance model p = 0.02). CONCLUSION This study demonstrated that pulmonary artery enlargement is more pronounced in Sch-PAH than IPAH, independently of mean pulmonary artery pressure level, suggesting that this is more likely a feature of Sch-PAH.