Cerebral Arteriovenous Shunting Linked to Liver Disease and Portal Hypertension

Background Development of portal hypertension in patients with liver pathology such as cirrhosis is due to vasoregulatory changes that occur both intrahepatically and systemically. Intrahepatic changes include increased synthesis of endothelin‐1 (ET‐1) and a decrease in nitric oxide (NO) production, increasing both intrahepatic vasoconstriction and resistance. In contrast, systemic effects of cirrhosis result in an increase in NO production, causing systemic vasodilation and decreased systemic vascular resistance. Additional effects of cirrhosis include systemic inflammation, widespread microvascular changes, and other hyperdynamic circulation abnormalities. Little is known of the association between liver dysfunction and development of cerebral vascular disease. We present three cases of atypical cerebral arteriovenous shunting in the setting of chronic liver disease, which is suggestive of a possible association. The aim of this patient series is to contribute to the understanding of cerebrovascular dysfunction as a systemic effect of liver disease. Methods We present three cases of similar atypical cerebrovascular shunting with a shared history of chronic liver disease. Results Case 1: A 62‐year‐old man with a history of HIV maintained on bictegravir, emtricitabine, and tenofovir alafenamide; diabetes mellitus II; cirrhosis (unknown etiology, likely non‐alcoholic steatohepatitis); and autoimmune gastritis presented with multiple spatially and temporally distinct deep and cortical spontaneous intraparenchymal hemorrhages. Digital subtraction angiography (DSA) demonstrated multifocal bilateral regions of tortuous, small‐caliber, vascular proliferation with associated early arteriovenous shunting. There was no clear target for intervention, and the patient was managed conservatively with blood pressure management and serial imaging. Case 2: A 56‐year‐old man with a history of chronic alcohol use presented with altered mental status, likely due to hepatic encephalopathy. CT angiography was concerning for a possible right‐sided dural arteriovenous fistula (dAVF). DSA demonstrated areas of microvascular proliferation with early arteriovenous shunting and a prominence of venous vasculature in the right hemisphere but no clear arteriovenous malformation (AVM) nidus or dAVF. He was managed conservatively. Case 3: A 53‐year‐old woman with a history of alcohol use disorder and a prior traumatic subdural hematoma requiring surgical evacuation presented with severe headache and left hemiparesis and was found to have a right‐sided intraparenchymal hemorrhage. Systemic workup revealed liver cirrhosis. DSA demonstrated a right frontoparietal AVM and multiple bilateral regions of early arteriovenous shunting located within the deep white matter and basal ganglia without an associated nidus. She underwent craniotomy for evacuation of intraparenchymal hemorrhage followed by staged embolization of the right‐sided AVM. The areas of arteriovenous shunting were managed conservatively. Conclusion These cases demonstrate abnormal patterns of cerebral arteriovenous shunting in the setting of chronic liver dysfunction, not previously characterized. These intracranial shunting patterns show similar morphology to intrahepatic vascular changes seen in liver pathologies, such as portal hypertension. These cases suggest a need for further investigation to better characterize the underlying pathophysiology of cerebrovascular disease in patients with chronic liver dysfunction.