Liver dysfunction is a well-documented complication in patients with congenital heart disease (CHD), primarily due to chronic venous congestion, reduced cardiac output, and hypoxemia. The pathophysiology involves hepatic congestion secondary to right-sided heart failure, leading to fibrosis and cirrhosis in advanced cases. While global studies have extensively explored this association, regional data, particularly from Egypt, remain limited. In this research we aim to investigate liver dysfunction in CHD patients, with a specific focus on research conducted in Assiut, Egypt, to address gaps in localized clinical understanding.
Hepatic complications are common in patients with CHD, resulting either from the primary cardiac defect or from palliative surgical procedures performed in infancy or childhood or from transfusion- or drug-related hepatitis. Given that such patients increasingly require the expertise of a hepatologist. There are several known associations between primary liver disease and concomitant CHD defects such as Abernethy malformation, Alagille syndrome, and Biliary Atresia Splenic Malformation syndrome (BASM).
However, hepatic disease as a result of CHD is more common than cardiac disease associated with liver disease. In these cases, hepatic dysfunction may ensue as a result of the primary cardiac defect or as a result of surgical palliation, especially in patients with single-ventricle physiology (e.g., tricuspid atresia). The mechanisms leading to hepatic dysfunction may be multifactorial. As an example, hepatic dysfunction may result from a combination of passive venous congestion of the liver and hypoxia, with the latter being driven by the CHD or concomitant pulmonary disease. Volume overload and low cardiac output may lead to both congestive hepatopathy and hepatic ischemia.
Several factors may interact to lead to end-stage liver disease. For example, patients with underlying liver disease (e.g., viral hepatitis, alcohol, or obesity) may be more susceptible to liver injury as a result of decreased functional mass. In addition, the presence of cardiac disease and subsequent passive congestion may itself predispose the liver to hepatic injury. Hypoxemia in cyanotic CHD further aggravates hepatocellular damage, necessitating routine hepatic monitoring in this population.
Globally, the prevalence of liver dysfunction in CHD varies, with studies reporting hepatic fibrosis in 30-40% of Fontan patients. Data from developing regions, including Egypt, are scarce. A recent study highlighted elevated liver enzymes in CHD patients, emphasizing the role of delayed surgical intervention in disease progression. Such findings underscore the necessity for expanded research on hepatic complications in Egyptian CHD cohorts.
Key risk factors for liver dysfunction in CHD include prolonged hypoxemia, high venous pressure, and prolonged duration of heart disease. Cyanotic CHD patients exhibit higher hepatic injury markers compared to acyanotic counterparts. In Egypt, socioeconomic barriers often delay corrective surgeries, exacerbating hepatic damage. Early intervention and regular hepatic surveillance are critical to improving outcomes.
Despite global advancements, Egyptian studies on CHD-related liver dysfunction are limited. A 2016 Cairo University study identified a high prevalence of abnormal liver function tests among CHD patients but lacked longitudinal follow-up. Further research is needed to establish region-specific diagnostic and therapeutic protocols, considering local healthcare challenges.
