Doppler Ultrasound Hepatic Vein Waveform as a Non-invasive Tool in the Assessment of Severity of Portal Hypertension

Overview

Portal hypertension is the result of an increased hepatic vascular resistance and portal inflow. The best established method to assess portal pressures is the determination of wedged hepatic venous pressure gradient (HVPG). Ultrasound Doppler technique is non-invasive in the assessment of portal hypertension as compared with invasive technique of measurement of the hepatic venous pressure gradient (HVPG). Hemodynamic measurements (BP and pulse recording) will be done and then patient will be given tablet Carvedilol 12.5 mg in a single dose and wait till the time that 20% reduction in heart rate from the baseline occurs. Haemodynamic measurements will be repeated to assess the acute response to beta-adrenoreceptor blocker agent. The change in the HWF will be recorded post beta-adrenoreceptor blocker administration.

Ultrasound Doppler technique is non-invasive in the assessment of portal hypertension as compared with invasive technique of measurement of the hepatic venous pressure gradient (HVPG). The Doppler waveform of the hepatic vein in healthy subjects is normally triphasic (two negative waves and one positive wave) because of central venous pressure variations due to the cardiac cycle. The normal triphasic hepatic vein waveform is transformed into a biphasic or monophasic waveform in patients with cirrhosis. A monophasic waveform has been shown to correlate with a high Child-Pugh score and a poor survival rate. Therefore, Hepatic vein waveform (HVWF) evaluation with Doppler US may be used as a supplemental tool to assess the severity of Portal Hypertension and therapeutic response to portal pressure lowering drugs in primary prophylaxis of variceal bleed in patients with large oesophageal varices. There's one study which has looked into the same topic but it has been conducted on alcoholic cirrhotics. Doppler ultrasound is a non-invasive tool in the measurement of portal pressure in portal hypertensive patients. Hemodynamic measurements (BP and pulse recording) will be done and then patient will be given tablet Carvedilol 12.5 mg in a single dose and wait till the time that 20% reduction in heart rate from the baseline occurs. Haemodynamic measurements will be repeated to assess the acute response to beta-adrenoreceptor blocker agent. The change in the HWF will be recorded post beta-adrenoreceptor blocker administration. This study will be a validation and interventional study. It is an open labeled study.