Echocardiography for the detection of portopulmonary hypertension in liver transplant candidates: An analysis of cutoff values

Abstract

Portopulmonary hypertension (POPH), a complication of chronic liver disease, may be a contraindication to liver transplantation (LT) because of the elevated risk of peritransplant and posttransplant morbidity and mortality. Because POPH is frequently asymptomatic, screening with echocardiography is recommended. The only reliable technique, however, for diagnosing POPH is right heart catheterization (RHC). The aims of this study were to evaluate the current estimated systolic pulmonary artery pressure (sPAP) cutoff value of 30 mm Hg and to determine a better cutoff value. One hundred fifty-two patients underwent pretransplant echocardiography between January 2005 and December 2010. These echocardiographic results were compared with pulmonary artery pressures measured during the pretransplant workup or at the beginning of the transplantation procedure (both by catheterization). With a cutoff value of 30 mm Hg, 74 of the 152 patients met the criteria for POPH on echocardiography, although the diagnosis was confirmed in only 7 patients during catheterization; this resulted in a specificity of 54%. It would have been more accurate to use a cutoff value of 38 mm Hg, which had a maximal specificity of 82% and, at the same time, guaranteed a sensitivity and negative predictive value of 100%. With the incorporation of the presence or absence of right ventricular dilatation, the specificity even increased to 93% for this new cutoff value. In conclusion, the prevalence of POPH was 4.6% among LT candidates in this study. We can recommend that LT candidates with an sPAP > 38 mm Hg should be referred for RHC. With the cutoff value increased from 30 to 38 mm Hg, the number of patients undergoing invasive RHC during their evaluation could be safely reduced. Liver Transpl 19:602-610, 2013. V C 2013 AASLD.Received November 11, 2012; accepted February 27, 2013. See Editorial on Page 573Portopulmonary hypertension (POPH), the presence of pulmonary hypertension in association with portal hypertension, is a known complication of chronic liver disease.1-9 Prospective studies and case-control studies have documented that POPH occurs in approximately 5% to 6% of patients with advanced liver disease. 5 In patients with portal hypertension, the association with pulmonary hypertension is seen in 2% to 6%.10,11 The incidence of POPH in patients referred for liver transplantation (LT) is 4% to 6%. 12Abbreviations: CO, cardiac output; LT, liver transplantation; mPAP, mean pulmonary artery pressure; mRAP, mean right atrial pressure; NA, not applicable; ND, not determined; NS, not significant; PCWP, pulmonary capillary wedge pressure; POPH, portopulmonary hypertension; PVR, pulmonary vascular resistance; RHC, right heart catheterization; RVEDD, right ventricular end-diastolic diameter; sPAP, systolic pulmonary artery pressure; SVR, systemic vascular resistance; TPG, transpulmonary gradient.

Respiratory Complication in Liver Disease

“…If RV dilatation was added to this variable, then the sensitivity remained acceptable, and the specificity and PPV improved to 92% and 41%, respectively. 66,67 A right heart catheterization is extremely important in differentiating POPH from hyper dynamic state because of liver disease and volume overload ( Table 3). When the mPAP is higher than 25 mm Hg, with a pulmonary capillary wedge pressure (PCWP) lower than 15 mm Hg and PVR higher than 240 dyn/s/cm À5 , then in the right clinical setting the diagnosis of POPH can be made.…”

Hepatopulmonary Syndrome and Portopulmonary Hypertension

“…TTE was noted to have a 97 % sensitivity and 77 % specificity to detect moderate to severe PAH prior to LT (Kim et al 2000). Based on different RVSP cutoffs, others have recommended that LT candidates with an RVSP > 38 mmHg should be referred for RHC (Raevens et al 2013a). More recently, the measurement of the main pulmonary artery diameter by computed tomography combined with echocardiography improved the accuracy in the diagnosis of POPH (Devaraj et al 2014).…”

The Art and Science of Diagnosing and Treating Lung and Heart Disease Secondary to Liver Disease

“…However, recent data on 152 patients undergoing pre-transplant echocardiography showed that a cutoff value of 30 mm Hg is associated with a specificity of 54%, resulting in unnecessary right-heart catheterizations, while a cutoff of 38 mm Hg yields a specificity of 82% and a sensitivity of 100%. 31 …”

“…The optimal timing of such TTE screening has not been defined, although most centers perform yearly TTEs to identify patients with echocardiographic parameters suggestive of PAH. 31 Furthermore, the performance of routine TTEs can identify patients with cirrhotic cardiomyopathy complicated by decreased left- and/or right-ventricular systolic function. Despite the sensitivity however of TTE to identify depressed cardiac function which places patients at risk of overt heart failure post-transplantation, there still is a risk for post-operative heart failure despite a normal pre-transplant TTE.…”