Portopulmonary hypertension and serum endothelin-1 levels in patients with liver cirrhosis.

A broad body of evidence has accrued, demonstrating the role of endothelin-1 (ET-1) in the pathophysiology of pulmonary arterial hypertension. Furthermore, the role of ET-1 as a causative pathophysiological mechanism of portopulmonary hypertension (POPH) has been consistently implicated; however, there is a lack of satisfactory evidence supporting this assertion. Thus, the present study aims to determine the prevalence of POPH among patients with hepatic cirrhosis, determine the serum ET-1 levels among these patients, and investigate the association between ET-1 and POPH in subjects with hepatic cirrhosis. A prospective, observational study was conducted from September 2017 to August 2018. Detailed history and examination with relevant investigations, including echocardiography, were performed for patients with and without POHP. ET-1 levels were significantly higher among patients with POPH compared to those without POPH. Moreover, the ET-1 cut-off level of 82 pg/mL correctly predicted the 9.3% prevalence of POPH in patients with hepatic cirrhosis with 100% sensitivity and 100% negative predictive value. The ET-1 cut-off level of 82 pg/mL may be used as a biomarker of POPH in patients with hepatic cirrhosis.