USE OF 2-D ECHO AND RIGHT HEART CATHETERIZATION FOR DIAGNOSIS OF PULMONARY HYPERTENSION IN PATIENTS EVALUATED FOR LIVER TRANSPLANTATION

Abstract

90 Background: Pulmonary hypertension (PHTN) is a recognized complication of end-stage liver disease and has been considered a relative contraindication for orthotopic liver transplantation (OLT). In this study, we sought to evaluate use of echocardiography (ECHO) as a screening tool for PHTN and to correlate ECHO findings with those seen on right heart catheterization (RHC). Methods: 178 patients, evaluated as potential candidates for OLT between 1995 and 1997 underwent 2-D ECHO. PASP was calculated by ECHO using the modified Bernoulli equation, and by RHC using pressure determinations at baseline and following volume challenge (1- liter crystalloid). PHTN was defined as pulmonary artery systolic pressure (PASP)≥ 30 mm Hg. Results:21 patients (12%) were found to have PHTN by ECHO. Mean age in this group was 48 years (range 41-65 years). There were 13 men and 8 women. Etiology of the liver disease was alcoholic cirrhosis in 14 patients (67%), hepatitis C virus in 3 (14%), primary biliary cirrhosis in 3 (14%) and cryptogenic cirrhosis in 1 (5%). Left ventricular function was normal in 18 patients (86%) and mildly depressed in 3 (14%). Of the 21 patients with PHTN identified by ECHO, 8 had PASP at rest consistent with PHTN by RHC. However, an additional 4 patients with normal resting PASP by RHC, developed PHTN after volume challenge. Therefore, ECHO correctly diagnosed PHTN in 12 out 21 patients (positive predictive value 57%, sensitivity 75%). On analysis of pulmonary capillary wedge pressure (PCWP) data, all patients with PHTN by ECHO (n=13) had normal PCWP while ⅝ patients (63%) with PHTN by both ECHO and RHC had elevated PCWP. Of the 12 patients with true PHTN, 4 were successfully transplanted to date and only one with severe PHTN (systolic 90 mm Hg) was turned down for OLT while the others are still one the waiting list. Conclusions: This experience suggests that ECHO provides a good screening tool for PHTN in OLT candidates. Although it frequently overestimates the resting PASP, it may identify a subset of patients with normal baseline RHC pressures who manifest volume-induced PHTN. Identification of patients with elevated PASP by ECHO offers the potential for preoperative risk stratification and optimized management.