A New Frontier: Endoscopic Ultrasound-Guided Portal Pressure Measurement: A Systematic Review and Meta-Analysis

Introduction: Portal hypertension is a major driving cause of complications and mortality in cirrhotic patients. Trans jugular hepatic venous pressure gradient (HVPG) is the current standard method for measuring hepatic venous pressure gradient and for determining portal hypertension. Endoscopic ultrasound-guided portal pressure gradient measurement (EUS-PPG) is a new modality where the portal pressure is measured by directly introducing a needle into the hepatic vein and portal vein. Also, there is an added advantage of performing variceal screening and liver biopsy in the same setting. This is the first systematic review and meta-analysis to evaluate the efficacy and safety of EUS-PPG. Methods: A comprehensive literature search was performed to identify pertinent studies. The primary outcomes assessed were technical and clinical success of EUS-PPG. Technical success was defined as successful introduction of the needle into the desired vessel while clinical success was defined as the correlation of the stage of fibrosis on the liver biopsy to EUS-PPG or concordance of HVPG and EUS-PPG. The secondary outcomes were pooled rates for total and individual adverse events related to EUS-PPG. Pooled estimates were calculated using random-effects models with a 95% confidence interval. Results: Eight cohort studies with total of 178 patients were included in our analysis. The majority of patients were males with an average age of 55.8 years. The calculated pooled rates for technical success and clinical success were 94.6 % (95% CI: 88.5%, 97.6%; P=0.00; I2=0) and 85.4% (95% CI: 51.5%, 97.0%; P=0.042; I2=70), respectively. The rate for total adverse events was 10.9% (95% CI: 6.5%, 17.7%; P=0.00; I2=4); 93.7% of adverse events were mild per ASGE lexicon. Abdominal pain (11%) was the most common adverse event followed (Figure 1). Conclusion: EUS-PPG is a safe and effective modality of diagnosing portal hypertension. With the direct measurement of pressure, no radiographic exposure, or intravenous contrast media, this technique has significant advantages over the current standard of care. Further randomized controlled trials are needed to validate our findings.Figure 1.: Forest plot showing the clinical success of EUS PPG.