RESUMO
Centers for the research of patients with pulmonary hypertension (PH) usually perform right cardiac catheterization (RHC) to document this hemodynamic condition; traditionally, the procedure is performed by the interventional cardiologist, while the interventional radiologist generally conducts the study of hepatic hemodynamics. In our center, where the leading cause of catheterization of the hepatic veins is orthotopic liver transplantation, the cardio-pulmonologist performs the procedure to diagnose the possibility of porto-pulmonary hypertension and its implications. Routine measurement of the hepatic venous pressure gradient (HVPG) during RHC is not recommended but is performed to confirm the diagnosis of portal hypertension (PoH). Our objective in this review was to graphically describe the technique of hemodynamic recording of suprahepatic veins in patients with chronic liver disease and PoH who are in liver transplant protocol. The concepts included in this manuscript are measuring portal pressure, the definition of the hepatic venous pressure gradient (HVPG), procedures for a correct measurement of the HVPG, techniques associated with a suprahepatic vein catheterization, contraindications, and complications of HVPG, and clinical applications of HVPG. Clinically significant PoH is defined as an increase in GPVH ≥10 mmHg. HVPG measurement is currently the best available method for assessing the presence and severity of PoH. The RHC is the standard gold method for diagnosing PoPH that confirms its existence and provides additional data to exclude other causes of PAH in liver transplant candidates.