Vascular anomalies associated with hepatic shunting

Abstract

Congenital vascular anomalies affecting the liver have been described in the scientific literature for decades. Understanding these malformations begins with knowledge of hepatic vascular embryology. Surgeons have applied numerous classification systems to describe both intrahepatic and extrahepatic shunts, which can confuse the reader and clinician. In our experience, focusing on one classification system for extrahepatic shunts and one for intrahepatic shunts is better. Today many patients with these shunts carry good long-term prognosis thanks to advances in imaging to better detect shunts earlier and classify them. Timely intervention by skilled radiologists and surgeons have also limited complications arising from dynamic shunts and can avoid a liver transplant. Congenital hepatic shunts are not the only vascular condition affecting the liver. Hereditary hemorrhagic telangiectasia, also known as Osler Weber Rendu syndrome, particularly type 2, may have varying severity of hepatic involvement which warrants longitudinal care from an experienced hepatologist. Lastly, congenital hemangiomas, often first identified on the skin and oral mucosa, also can affect the liver. While most will resolve in infancy and childhood, the pediatric hepatologist must understand how and when to treat persistent lesions and their complications. This article serves as a concise reference to help clinicians better care for patients with these rare conditions.

Congenital Portosystemic Shunts: Variable Clinical Presentations Requiring a Tailored Endovascular or Surgical Approach

“… 11 Large or multiple hepatic hemangiomas can have an increased risk of high vascular flow resulting in hemodynamic instability and heart failure. 12 Pulmonary hypertension in neonates can be associated with congenital portosystemic shunts. The pathophysiology is incompletely understood, but it is thought to be secondary to fluid overload as well as a lack of hepatic clearance of vasoactive substances.…”

“…The pathophysiology is incompletely understood, but it is thought to be secondary to fluid overload as well as a lack of hepatic clearance of vasoactive substances. 12 In some patients with CPSS, shunt closure or liver transplantation may prevent the progression of pulmonary hypertension. 13 Hepatic tumors can develop from altered hemodynamics secondary to insufficient portal vein perfusion and compensatory increased hepatic arterial flow.…”

“…The differential for macrovascular shunts includes infradiaphragmatic total anomalous pulmonary venous return, arteriovenous malformations, infantile hepatic hemangiomas, arterioportal fistula, and portosystemic shunts 11. Large or multiple hepatic hemangiomas can have an increased risk of high vascular flow resulting in hemodynamic instability and heart failure 12. Pulmonary hypertension in neonates can be associated with congenital portosystemic shunts.…”

Right hemihepatectomy combined with ligation of the common hepatic artery and gastroduodenal artery for the treatment of intrahepatic HHT: A case report

“…Georghiou et al successfully cured pulmonary arteriovenous malformation by lobectomy ( 14 ). A recent report suggested that partial liver resection is also an option for large intrahepatic shunts that do not close spontaneously ( 15 ). Petrovic et al reported a successful left lateral bisegmentectomy in a HHT patient with liver abscess ( 16 ).…”

Hepatic pseudolesions caused by alterations in intrahepatic hemodynamics

“…Causes of increased hepatic arterial blood flow include HABR due to decreased portal blood flow and the presence of congenital or acquired shunt pathways [ e.g. , hepatic AP shunts), hepatic arterial–hepatic venous shunts (AV shunts)], hereditary hemorrhagic telangiectasia (Figure 2 ), hepatic trauma, and others[ 11 ].…”