MRI assessment for beta-blockers in portal hypertension

INTERVENTION: Patients with liver cirrhosis who were about to commence non‐selective beta‐blocker (NSBB) therapy as part of clinical management of portal hypertension (PHT) are enrolled into the study. Upon enrolment, information on liver disease aetiology, past medical history, medication and alcohol history, and results of the most recent upper gastrointestinal endoscopy are recorded. Prior to starting NSBB therapy, patients undergo a physical examination and routine laboratory investigations (full blood count, coagulation screen, liver and renal function tests), followed by a baseline research MRI scan (phase‐contrast MR angiography, liver and spleen T1 mapping). Liver disease severity is also assessed at baseline according to Model for End Stage Liver Disease (MELD) and Child‐Pugh score. Patients are randomised in a 1:1 ratio to once‐daily treatment with carvedilol or modified‐release propranolol at an initial dose of 6.25mg or 80mg respectively. Patients’ compliance with medication and adverse event monitoring are assessed at an initial follow‐up visit after 1 week of NSBB therapy. Provided that NSBB are tolerated clinically and haemodynamically (resting heart rate (HR) =50 beats per minute (b.p.m), systolic blood pressure =95 mmHg), the dose is escalated to the clinical target dose of 12.5mg of carvedilol or 160mg of propranolol. Further treatment compliance and adverse event monitoring takes place by weekly telephone consultations. After 4 weeks, when established on NSBB, the second research MRI scan is performed. An interval of 4 weeks has been chosen as haemodynamic responses to NSBB after chronic use exceed the acute response rate. Consistent with a previous landmark NSBB trial in PHT, treatment is targeted at a resting HR reduction of more than 25% from baseline; this was defined as a clinical haemodynamic response to NSBB (HR responders). Following the study, participants continue taking NSBB and are managed by their existing NHS consultant. CONDITION: Portal hypertension ; Circulatory System ; Portal hypertension PRIMARY OUTCOME: Volumetric blood flow [L/min] in selected blood vessels (proper hepatic artery, portal vein, superior mesenteric artery, superior aorta, inferior aorta, renal arteries and azygous vein) measured by phase‐contrast MR angiography at baseline and 4 weeks. SECONDARY OUTCOME: Correlation between MRI blood flow measurements and liver disease severity (using MELD and Child‐Pugh scores) assessed at baseline and at 4 weeks.; INCLUSION CRITERIA: 1. Male or female patients aged 18‐80 with liver cirrhosis 2. Portal hypertension in whom commencement of beta‐blockers is clinically indicated