Disorders of the Hepatic and Mesenteric Circulation(beta)
Official guideline of the American College of Gastroenterology.
Bleeding and Thrombotic Risk in Liver Disorders
We do not recommend FFP to improve thrombin generation in patients with cirrhosis at conventional doses (10 mL/kg). If sufficient volume is given (1–2 L) to lower a significantly prolonged INR, volume expansion increases portal pressure and may trigger variceal hemorrhage. Thus in most situations, infusion of plasma prophylactically to decrease bleeding risk is futile and potentially risky.
We do not recommend antifibrinolytic agents such as epsilon aminocaproic acid and tranexamic acid to reduce bleeding in the absence of hyperfibrinolysis. These agents are not generally considered to induce a hypercoagulable state but require caution if pathological clot such as PVT is already present.
We do not recommend prophylactic platelet transfusions before common procedures such as routine variceal banding or paracentesis outside of significant renal dysfunction (serum creatinine >2.5 mg/dL) or sepsis. Existing data indicate a somewhat tenuous relationship between bleeding risk and platelet count. In vitro studies demonstrate adequate thrombin production with platelet levels ≥50,000/mL. Infusion of a single adult platelet dose does not improve thrombin generation. Higher platelet levels may be more appropriate for high-risk procedures such as removal of large polyps and major surgery, but will probably require higher doses of platelet infusions; if the procedure is elective, the use of TPO agonists may be more appropriate.
Portal and Mesenteric Vein Thrombosis
We recommend Doppler ultrasound examination as the initial noninvasive modality for diagnosis of PVT. Contrast-enhanced CT or MRI scan is recommended to assess the extension of thrombus into the mesenteric veins and to exclude tumor thrombus among patients with cirrhosis who develop new portal and/or mesenteric vein thrombus.
We recommend anticoagulation for all noncirrhotic patients with acute symptomatic portal or mesenteric vein thrombosis in the absence of any contraindication.
We suggest anticoagulation for patients with chronic PVT if there is (i) evidence of inherited or acquired thrombophilia, (ii) progression of thrombus into the mesenteric veins, or (iii) current or previous evidence of bowel ischemia.
We suggest at least 6 months of anticoagulation in patients with portal or mesenteric vein thrombosis without a demonstrable thrombophilia and when the etiology of the thrombosis is reversible. Indefinite anticoagulation is recommended in patients with portal or mesenteric vein thrombosis and thrombophilia.
We recommend anticoagulation for patients with (i) acute complete main PVT, (ii) MVT, or (iii) extension of portal venous thrombosis into mesenteric veins. Risk of bleeding must be weighed against benefits as for example, in patients with platelets <50,000/μL or hepatic encephalopathy at risk of falls.
We suggest anticoagulation in patients with chronic PVT only if there is (i) evidence of inherited thrombophilia, (ii) progression of thrombus, or (iii) history of bowel ischemia due to thrombus extension into the mesenteric veins. Anticoagulation may also be considered in patients awaiting LT.
We recommend nonselective beta-blockers for prevention of variceal bleeding in patients with high-risk varices and portal and/or mesenteric vein thrombosis requiring anticoagulation. Endoscopic variceal ligation may be performed if there are contraindications or intolerance to beta-blockers; however, anticoagulation may need to be interrupted in the periprocedural period.
We recommend nonselective beta-blockers for primary prevention of variceal bleeding in cirrhotic patients with high-risk varices and portal and/or mesenteric vein thrombosis requiring anticoagulation. Endoscopic variceal ligation may be performed if there is a contraindication to or intolerance to beta-blockers; however, anticoagulation may need to be interrupted in the periprocedural period.
We suggest either unfractionated heparin or LMWH be used once a decision is made to initiate anticoagulation for treatment of portal and/or MVT. However, pros and cons of either approach should be considered before initiating either regimen.
We suggest either LMWH or warfarin be used. Although this field continues to evolve, there is currently only limited experience with DOACs, which includes Xa or thrombin inhibitors. Because absorption of these agents may be limited in the presence of intestinal edema, some monitoring of therapy is recommended. A normal thrombin time and aPTT for dabigatran and a normal prothrombin time or anti-Xa activity for apixaban and rivaroxaban rule out substantial drug effect. Pros and cons of all approaches including availability of reversal agents should be considered before deciding on the specific regimen.
We suggest either unfractionated heparin or LMWH for treatment of portal and/or MVT once a decision is made to initiate anticoagulation. Unfractionated heparin is preferred in the presence of renal insufficiency, and LMWH is preferred in the presence of thrombocytopenia.
We recommend Doppler US as the initial diagnostic test for evaluation for BCS. Contrast-enhanced CT or MRI scans should be obtained to assess thrombus extension, rule out tumor thrombus, determine response to anticoagulation therapy, evaluate indeterminate hepatic nodules, and whenever there is high clinical suspicion of BCS despite negative or inconclusive Doppler US results.
We recommend stepwise management from least to most invasive therapies for patients with BCS. Systemic anticoagulation is the initial treatment of choice. If medical therapy fails, as determined by worsening liver and/or renal function, ascites, or hepatic encephalopathy, then endovascular therapies such as angioplasty or TIPS are recommended. LT is reserved for TIPS failure and BCS presenting as fulminant liver failure.
Mesenteric Artery Aneurysms
We suggest treatment in asymptomatic patients only with aneurysms of the pancreaticoduodenal and gastroduodenal arcade, intraparenchymal hepatic artery branches, women of childbearing age, and recipients of a liver transplant, irrespective of aneurysm diameter. In asymptomatic patients with mesenteric aneurysms <2 cm in diameter and not meeting the aforesaid criteria, follow-up imaging is recommended initially in 6 mo, then at 1 yr and subsequently every 1–2 yr. We recommend that mesenteric artery aneurysms associated with symptoms (abdominal pain in the absence of other causes) be treated.
Hereditary Hemorrhagic Telangiectasia
We do not recommend routine screening for LVMs in patients with HHT. There is no evidence to suggest that making a diagnosis in an asymptomatic patient has clinical benefits or prevents death. However, those with a liver bruit, hyperdynamic circulation, or liver test abnormalities should be further evaluated for LVMs. Of note, women with HHTand LVMs who become pregnant warrant special attention due to anticipated hemodynamic stress.
We suggest contrast CT scan or MRI/MRCP in patients with HHT who develop symptoms/signs of heart failure, biliary ischemia, hepatic encephalopathy, mesenteric ischemia, or PH. Doppler US may establish a diagnosis of LVMs in patients with HHT and a compatible clinical picture, but is less accurate than CT scan or MRI/MRCP. Angiography and/or liver biopsy are not recommended in the diagnosis of LVMs.
We recommend standard medical therapy for each complication of liver VMs in patients with HHT, which results in symptom resolution in the majority. In nonresponders to standard therapy, management should be undertaken at specialized centers using a multidisciplinary approach. Bevacizumab should be considered in patients with HOHF and possibly for other complications of LVM before using invasive therapies, although not all patients respond. Symptoms recur after treatment discontinuation, and bevacizumab can be associated with significant side effects. Transarterial hepatic artery embolization or surgical ligation is proscribed in patients with biliary involvement or PH, and there is insufficient evidence to recommend its use in HOHF. Liver transplant is an important option for nonresponders to standard treatment or patients who relapse after medical treatment, but criteria for listing are not clearly defined, the procedure may be associated with a high rate of perioperative complications, and liver VMs may recur as early as 6 yr after transplant.
How strong is the ACG's recommendation?