Pulmonary artery enlargement in schistosomiasis associated pulmonary arterial hypertension

Abstract

BackgroundSchistosomiasis 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.MethodsWe retrospectively evaluated patients with IPAH (n = 25) and Sch-PAH (n = 22) who underwent computed tomography pulmonary angiogram and right heart catheterization.ResultsSch-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).ConclusionThis 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.

Pulmonary Hypertension: Definition, Classification, and Diagnosis

“…35,36 Furthermore, the clinical and hemodynamic findings of Sch-PAH are also similar to that of IPAH, 37 although with some specific radiological features. 38 Mortality rate seems to be better in Sch-PAH, reaching up to 15% at 3 years, in the absence of a specific therapy. Finally, the response to targeted therapies in Sch-PAH is also similar to other forms of PAH with improvements in hemodynamics and exercise capacity.…”

“…The initial evaluation of dyspnea may be normal in the early stages of PH or may already evidence abnormalities related to the pulmonary vascular territory. 38 In general, the diagnostic investigation is quite extensive and should encompass all the major mechanisms that culminate in the development of PH. The following constitute the main tests with their most significant findings in PH:…”

Pulmonary Vascular Diseases Secondary to Schistosomiasis

“…It was demonstrated that pulmonary artery enlargement is more pronounced in schistosomiasis-induced PAH than an- other form of PAH, suggesting that this is a more distinct feature of schistosomiasis-induced PAH (Figure 3). [43][44][45] Electrocardiography may show right ventricular hypertrophy or strain and right atrial enlargement, and may also reveal a right bundle branch block. Echocardiography may demonstrate right ventricular dilatation, potentially compressing the left ventricle with septal bowing, usually accompanied by right atrial dilation, tricuspid valve regurgitation, and an increased pressure gradient across the tricuspid valve as well as dilatation of the main pulmonary artery.…”

Schistosomiasis and pulmonary hypertension

“…Pulmoner vasküler dilatasyonun pulmoner arter basıncından bağımsız olduğu ileri sürülmüştür. Bu radyolojik bulgunun hastalığın yavaş progresyonuna veya özel bir adaptasyon mekanizmasına bağlı olabileceği düşünülmektedir (11).…”