Introduction
Cirrhosis usually results from the conversion of normal liver architecture into structurally abnormal nodules due to tissue fibrosis. According to the current knowledge, cirrhosis’s 1-year mortality rate may range from 1% to as high as 57%, and it is a leading cause of morbidity and mortality, especially in developed nations (1). Alcoholic liver disease and chronic infections due to hepatitis-B and -C viruses constitute the leading causes of liver cirrhosis worldwide (2). Clinically, cirrhosis is categorized into two configurations: either as compensated or decompensated. Although compensated cirrhosis is difficult to distinguish from chronic hepatitis infection, decompensated cirrhosis is easily diagnosed because it has several specific clinical and laboratory findings, such as ascites, hepatic encephalopathy, gastrointestinal bleeding, thrombocytopenia, and hypoalbuminemia. In addition, cirrhotic patients can be classified into two configurations based on the absence or presence of PH (portal hypertension) (3), a condition characterized by a hepatic venous pressure gradient of ≥5 mmHg and the main mechanism leading to mortality in cirrhotic patients (4).
PAH (pulmonary arterial hypertension) is categorized into five major forms based on the WHO (World Health Organization) recommendation, and PAH due to portal hypertension, which is termed PoPH (porto-pulmonary hypertension), is included in group I. PoPH is most commonly found in cases with cirrhosis, and it develops in approximately 1-5% of subjects with PH (5, 6). Hence, PoPH screening is crucial in subjects with chronic liver disease; TTE (transthoracic echocardiography) is the best non-invasive applicable tool for such screening (7).
PAS (pulmonary artery stiffness) is a simple, easily measurable echocardiographic variable that can be obtained by dividing the peak velocity of the pulmonary flow by the PfAT (pulmonary flow acceleration time). A prior clinical study found that echocardiographically-obtained PAS parameters were well correlated with the measurements obtained from right heart catheterizations (8). Moreover, PAS can represent early changes in the pulmonary vascular region in congenital cardiac disease cases without significant PAH (8). In the current literature, several studies show that PAS is linked with RV (right ventricular) dysfunction, PAH, and disease severity in subjects with structural cardiac disease, HIV (human immunodeficiency virus), and chronic lung disease (8-12). However, to our knowledge, no prior research has evaluated PAS in cirrhotic patients. Hence, our main aim was to use PAS to show the early changes in the pulmonary vascular region in subjects with cirrhosis.