There are a lot of reviews published on the prevalence of hepatitis C virus (HCV) all over the world. It is estimated that 13–14% of all HCV infections are genotype4 (G4) [1]; the majority of G4 presents in Egypt, Northern Africa, the Middle East, and Sub-Saharan Africa [2]. Egypt has one of the highest burdens of chronic HCV infections globally; it is estimated that the prevalence of HCV in our country is around 4.5 to 6.7% [3, 4]. Chronic HCV is a leading cause of mortality and morbidity worldwide due to complications of liver cirrhosis (LC), hepatocellular carcinoma (HCC), and portal hypertension [5].
LC is the most common cause of portal hypertension, and variceal bleeding is considered the most serious complication of portal hypertension [6]. Initially, portal pressure increases as a consequence of increased resistance to blood flow due to the formation of regenerative nodules and fibrous tissue [7]. Also, there is intrahepatic vasoconstriction which accounts for 25% of the increased intrahepatic resistance, and mostly, that is due to a decrease in the intrahepatic production of vasodilators substance as nitric oxide [7].
Portal hypertension in LC can be treated with many drugs such as beta blockers but without any regression in the underlying pathology, and portal hypertension may be increased with time [8, 9]. Direct antiviral agents (DAAS) are very effective, safe, and changing the burden and prognosis of the disease [3]. Sustained virological response (SVR) is achieved in more than 95% of the chronic HCV patients and is associated with regression in the underlying pathology, improvement in liver function, fibrosis, and overall survival [9]. Also, portal hypertension is predicted to be improved with virological response, according to the improvement in liver fibrosis and inflammation [10]. In chronic hepatitis C patients treated with DAAS, the progression of cirrhosis can be reversed with treatment [11, 12]. Elimination of the infection allows the liver to start a slow process of renewal but within limits, as this process may not happen in patients with advanced stages of liver cirrhosis [13, 14].
Doppler ultrasonography (US) helps us to examine the hemodynamics of the abdominal vessels including portal circulation. Thus, many investigators have confirmed the usefulness of abdominal Doppler US in assessing portal pressure in cirrhotic patients. It would be highly preferred to have any Doppler parameter to be a suitable alternative for the current invasive gold standard of measuring hepatic venous pressure gradient (HVPG) for assessing portal hypertension [15].
Doppler ultrasonography has an advantage of being non-invasive; so, many parameters have been made to evaluate the hemodynamic changes in patients with liver cirrhosis and the response to medical treatment of portal hypertension [16]. Doppler parameters, which have been commonly used for assessing portal hypertension, include the measurement of portal and splenic venous blood flows and velocity and the pulsatility and resistive index at hepatic, superior mesenteric, splenic, and renal artery [15, 16]. Doppler ultrasonography has been widely used to measure the portal blood flow velocity before and after DAAS administration in cirrhotic patients infected with HCV as a non-invasive, and easy-to-perform diagnostic imaging tool and to identify the impact of treatment on the portal circulation [16, 17].
We aim to evaluate the effect of direct-acting antiviral therapy on portal circulation hemodynamics in cirrhotic patients infected with HCV