Spleen Size in Idiopathic and Heritable Pulmonary Arterial Hypertension

Abstract

Background: It is unknown whether the spleen size correlates with disease severity and outcome in patients with idiopathic and heritable pulmonary arterial hypertension (PAH). Objectives: To determine the prevalence of splenomegaly in PAH and assess whether it correlates with severity of disease and outcome. Methods: We identified subjects with either heritable or idiopathic PAH who had Doppler echocardiography, right-heart catheterization and computed tomography (CT) of the chest and/or abdomen that included the spleen. Results: We included 62 subjects with a mean age (±SD) of 49 (±15) years; 82% were women. Spleen dimensions were 10 (±3), 6 (±2) and 9 (±2) cm for the craniocaudal length, thickness and width measurements, respectively. The median [interquartile range (IQR)] spleen volume was 344 (225-533) cm³. Splenomegaly was observed in 52-63% of the patients, depending on the formula used. The spleen volume was not associated with clinical, echocardiographic or hemodynamic variables. Spleen volume was not associated with adjusted mortality. We studied the characteristics of the spleen during autopsy in 9 patients with idiopathic PAH who died of right-heart failure. The mean (IQR) spleen weight was 220 (151-325) g. We observed early congestion in all but 2 patients who had chronic congestion. Conclusions: Splenomegaly of predominantly mild degree is common in idiopathic and heritable PAH. However, spleen size was not associated with clinical, echocardiographic, hemodynamic and survival data in these patients.