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.