Current management approaches to portopulmonary hypertension

Portopulmonary Hypertension: A Review of the Current Literature

Portopulmonary hypertension is defined as the development of pulmonary arterial hypertension in the setting of portal hypertension with or without liver cirrhosis. Portal hypertension-associated haemodynamic changes, including hyperdynamic state, portosystemic shunts and splanchnic vasodilation, induce significant alterations in pulmonary vascular bed and play a pivotal role in the pathogenesis of the disease. If left untreated, portopulmonary hypertension results in progressive right heart failure, with a poor prognosis. Although Doppler echocardiography is the best initial screening tool for symptomatic patients and liver transplantation candidates, right heart catheterisation remains the gold standard for the diagnosis of the disease. Severe portopulmonary hypertension exerts a prohibitive risk to liver transplantation by conferring an elevated perioperative mortality risk. It is important for haemodynamic parameters to correspond with non-severe portopulmonary hypertension before patients can proceed with the liver transplantation. Small uncontrolled studies and a recent randomised controlled trial have reported promising results with vasodilatory therapies in clinical and haemodynamic improvement of patients, allowing a proportion of patients to undergo liver transplantation. In this review, the epidemiology, pathogenesis, diagnostic approach and management of portopulmonary hypertension are discussed. We also highlight fields of ongoing investigation pertinent to risk stratification and optimal patient selection to maximise long-term benefit from currently available treatments.

Cardiovascular manifestation of end-stage liver disease and perioperative echocardiography for liver transplantation: anesthesiologist’s view

Liver transplantation (LT) is the curative therapy for decompensated cirrhosis. However, anesthesiologists can find it challenging to manage patients undergoing LT due to the underlying pathologic conditions of patients with end-stage liver disease and the high invasiveness of the procedure, which is frequently accompanied by massive blood loss. Echocardiography is a non-invasive or semi-invasive imaging tool that provides real-time information about the structural and functional status of the heart and is considered to be able to improve outcomes by enabling accurate and detailed assessments. This article reviews the pathophysiologic changes of the heart accompanied by cirrhosis that mainly affect hemodynamics. We also present a comparative review of the diagnostic criteria for cirrhotic cardiomyopathy published by the World Congress of Gastroenterology in 2005 and the Cirrhotic Cardiomyopathy Consortium in 2019. This article discusses the conditions that could affect hemodynamic stability and postoperative outcomes, such as coronary artery disease, left ventricular outflow tract obstruction, portopulmonary hypertension, hepatopulmonary syndrome, pericardial effusion, cardiac tamponade, patent foramen ovale, and ascites. Finally, we cover a number of intraoperative factors that should be considered, including intraoperative blood loss, rapid reaccumulation of ascites, manipulation of the inferior vena cava, post-reperfusion syndrome, and adverse effects of excessive fluid infusion and transfusion. This article aimed to summarize the cardiovascular manifestations of cirrhosis that can affect hemodynamics and can be evaluated using perioperative echocardiography. We hope that this article will provide information about the hemodynamic characteristics of LT recipients and stimulate more active use of perioperative echocardiography.

Progressive dyspnoea in a patient with idiopathic non-cirrhotic portal hypertension

This case of progressive dyspnoea in a 43-year-old with idiopathic non-cirrhotic portal hypertension highlights important pulmonary vascular complications of chronic liver diseasehttps://bit.ly/3rwEkhP

Long-term outcome in liver transplantation candidates with portopulmonary hypertension

Portopulmonary hypertension (PoPH) is diagnosed in 2-6% of liver transplantation (LT) candidates. We studied outcomes of candidates for LT suffering from PoPH. Data were collected retrospectively from a prospective registry. Pulmonary hemodynamic variables were collected at the time of PoPH diagnosis, at last evaluation before LT, and within 6 months and beyond 6 months after LT. Forty-nine patients (35 males, 48 ± 8 years) were analyzed (median Model for End-Stage Liver Disease score 20). At baseline, mean pulmonary artery pressure (mPAP) was 44 ± 10 mm Hg (range 26-73 mm Hg), cardiac index was 3.5 ± 0.9 L/min/m² , and pulmonary vascular resistance was 5.6 ± 2.8 Wood units. Hemodynamic reassessment performed in 35 patients who were treated with pulmonary arterial hypertension-targeted therapies before LT resulted in significant decreases in both mPAP (36 ± 7 versus 47 ± 10 mm Hg, P < 0.0001) and pulmonary vascular resistance (3.0 ± 1.4 versus 6.1 ± 3.1 Wood units, P < 0.0001). Fourteen patients (29%) died without having had access to LT. Thirty-five patients underwent LT and were followed up for a median of 38 months. Eight patients (23%) died after LT including 5 due to PoPH (after 1 day to 6 months). Among survivors (n = 27), all patients treated with intravenous epoprostenol were weaned off post-LT, and endothelin receptor antagonist or phosphodiesterase type 5 inhibitors were continued in 15/27 patients (55%). At last evaluation, 20/27 patients (74%) had mPAP <35 mm Hg and 8 of them (30%) had mPAP <25 mm Hg. Overall survival estimates after LT were 80%, 77%, and 77% at 6 months, 1 year, and 3 years, respectively.

CONCLUSION

Stabilization or reversibility of PoPH seems to be an attainable goal using the combination of pulmonary arterial hypertension-targeted therapies and LT in patients who are transplantation candidates. (Hepatology 2017;65:1683-1692).

[Portopulmonary hypertension: Updated review]

Portopulmonary hypertension (PPH) is a rare condition worldwide, although epidemiological data are unknown in Mexico. However, chronic liver diseases are very prevalent in Mexico. PPH is the 4th subtype in frequency in the group of pulmonary arterial hypertension. Its diagnosis is made within 2 scenarios: patients with suspected pulmonary hypertension and candidates for orthotopic liver transplantation (OLT). Both echocardiogram and a right cardiac catheterisation are crucial for diagnosis in both cases. PPH is a challenge for OLT, since it can significantly increase perioperative mortality. The use of specific therapy is the cornerstone of this disease, as a measure to improve the outcome of those who become candidates for OLT with moderate to severe PPH. It is important to recognise that PPH can be a contraindication to OLT. The role of lung-liver transplantation or heart-lung-liver transplantation as a measure to heal pulmonary vascular disease in patients with PPH is still uncertain.

Portopulmonary hypertension

Portopulmonary hypertension (PoPH) refers to the condition that pulmonary arterial hypertension (PAH) occur in the stetting of portal hypertension. The development of PoPH is thought to be independent of the severity of portal hypertension or the etiology or severity of liver disease. PoPH results from excessive vasoconstriction, vascular remodeling, and proliferative and thrombotic events within the pulmonary circulation that lead to progressive right ventricular failure and ultimately to death. Untreated PoPH is associated with a poor prognosis. As PoPH is frequently asymptomatic or symptoms are generally non-specific, patients should be actively screened for the presence of PoPH. Two-dimensional transthoracic echocardiography is a useful non-invasive screening tool, but a definitive diagnosis requires invasive hemodynamic confirmation by right heart catheterization. Despite a dearth of randomized, prospective data, an ever-expanding clinical experience shows that patients with PoPH benefit from therapy with PAH-specific medications including with endothelin receptor antagonists, phosphodiesterase-5 inhibitors, and/or prostanoids. Due to high perioperative mortality, transplantation should be avoided in those patients who have severe PoPH that is refractory to medical therapy.

"Porto-pulmonary hypertension: a comprehensive review"

Porto-pulmonary hypertension (PoPH) is a rare but threatening vasculopathy, defined by the presence of pulmonary arterial hypertension (PAH) in the setting of portal hypertension. Although most commonly observed in cirrhotic patients, those with non-cirrhotic portal hypertension are also at risk of developing it. Little is known about the mechanisms by which PAH develop in patients with portal hypertension, but genetic factors, pulmonary vascular wall shear stress, and a dysregulation of vasoactive, proliferative and inflammatory mediators might be involved. PoPH is estimated to occur in 3 to 10% of patients with end-stage liver disease, although its frequency is not related to the severity of liver dysfunction or the degree of portal hypertension. Moderate-to-severe PoPH portends an extremely poor prognosis. Presentation is highly variable, therefore a high index of suspicion is required to establish the diagnosis. PoPH should be screened by transthoracic echocardiography (TTE) in cirrhotic patients presenting with dyspnoea as well as in all patients being evaluated for liver transplantation (LT) regardless of their symptoms. If TTE shows elevated pulmonary pressures, patients should undergo right heart catheterisation, which is required for the definitive diagnosis of PoPH. Without LT, the overall 5-year mortality in PoPH patients is 70%, but it should not be considered an indication for LT. Moderate-to-severe PoPH contraindicates LT, since it is associated with a prohibitively increased intra and postoperative mortality. However, there is now evidence supporting the use of PAH-specific therapies pre-LT in order to improve pulmonary haemodynamic measurements, so the procedure can then be performed with significantly lower risks.

Living-donor liver transplantation for congenital biliary atresia with porto-pulmonary hypertension and moderate or severe pulmonary arterial hypertension: Kyoto University experience

Porto-pulmonary hypertension with moderate or severe pulmonary arterial hypertension (PAH) is viewed as a contraindication to liver transplantation (LT) because of associated poor outcomes; however, patients with biliary atresia (BA) are generally good candidates for LT. Ten patients with moderate/severe PAH underwent living-donor liver transplantation (LDLT) at our institution; eight of these patients had BA and were the focus of this study. Preoperative therapies, including prostaglandin (PG)I2 , were introduced. When mean pulmonary arterial pressure (mPAP) after treatment was <40 mmHg or initial mPAP without therapy was <35 mmHg, we performed an acute volume challenge test to evaluate right ventricular function. LDLT was performed when mPAP after anesthetic induction was confirmed at ≤35 mmHg. Six patients had favorable responses to preoperative treatment and catheter testing, but two patients showed poor responses. The two patients with poor responses had poor clinical courses with unstable mPAP after LDLT. The other six patients had successful courses with well-controlled mPAP, and PGI2 was withdrawn or weaned following LDLT. Survival did not significantly differ between the eight BA recipients with moderate/severe PAH and 77 age-matched BA recipients without PAH from the same time period. LDLT has major benefits for BA patients with well-controlled PAH.

[Management of decompensated liver cirrhosis in the intensive care unit]

Liver cirrhosis is the end-stage of long-standing chronic liver diseases. The occurrence of complications from liver cirrhosis increases the mortality risk, but the prognosis can be improved by optimal management in the intensive care unit (ICU). Defined diagnostic algorithms allow the etiology and presence of typical complications upon presentation to the ICU to be identified. Acute variceal bleeding requires endoscopic intervention, vasoactive drugs, antibiotics, supportive intensive care measures and, where necessary, urgent transjugular intrahepatic portosystemic shunt (TIPS) procedure. Spontaneous bacterial peritonitis needs to be diagnosed and immediately treated in patients with ascites. Hepatorenal syndrome should be treated by albumin and terlipressin. In case of respiratory failure, differential diagnosis should not only consider pneumonia, pulmonary embolism and cardiac failure, but also hepatic hydrothorax, portopulmonary hypertension and hepatopulmonary syndrome. The feasibility of liver transplantation should be always discussed in patients with decompensated cirrhosis. Artificial liver support devices may only serve as a bridging procedure until transplant.

Living-donor liver transplantation for moderate or severe porto-pulmonary hypertension accompanied by pulmonary arterial hypertension: a single-centre experience over 2 decades in Japan

BACKGROUND

Candidates for orthotopic liver transplantation (OLT) often have porto-pulmonary hypertension (PPHTN) with pulmonary arterial hypertension (PAH). Poor outcomes of PPHTN contraindicate OLT. There are no guidelines for living-donor liver transplantation (LDLT) in PPHTN patients.

METHODS

We present our experiences of LDLT in six patients with moderate or severe PPHTN, along with our institutional guidelines. Three had liver cirrhosis and three were non-cirrhotic. Catheterization studies were undertaken before, during and after LDLT, and the mean pulmonary arterial pressure (mPAP), cardiac output (CO), pulmonary vascular resistance and total peripheral resistance (TPR) were monitored.

RESULTS

The results showed significant differences in CO and TPR between cirrhotic and non-cirrhotic patients before, during and after LDLT. Cirrhotic patients showed systemic hyperdynamic state. Two cirrhotic patients showed poor responses to pre-transplant treatment, and continued to have increased PAH and poor clinical courses after LDLT. LDLT has an advantage of flexible timing of LT. Currently in our institution, PPHTN patients with mPAP <40 mmHg are registered for LDLT after treatment and catheterization. However, LDLT is performed when mPAP is ≤35 mmHg, leading to improved outcomes.

CONCLUSION

PPHTN patients with well-controlled PAH, or secondary PAH resulting from porto-systemic shunts, may be appropriate candidates for LDLT after careful considerations.

Liver transplantation: Advances and perioperative care

Liver transplantation is one of the treatments for many-life threatening liver diseases. Numerous advances in liver transplant surgery, anaesthesia and perioperative care have allowed for an increasing number of these procedures. The purpose of this review is to consider some of the important advances in perioperative care of liver transplant patients such as pre-operative evaluation, intraoperative monitoring and management and early extubation. A PubMed and EMBASE search of terms “Anaesthesia” and “Liver Transplantation” were performed with filters of articles in “English”, “Adult” and relevant recent publications of randomised control trial, editorial, systemic review and non-systemic review were selected and synthesized according to the author's personal and professional perspective in the field of liver transplantation and anaesthesia. The article outlines strategies in organ preservation, training and transplant database for further research.

Pulmonary hypertension in liver transplant

PURPOSE OF REVIEW

Pulmonary hypertension patients provide challenging issues to anesthesiology. The condition is more so when it is associated with liver transplant surgery. This situation is especially true when associated with portopulmonary hypertension (POPH), a subdivision of pulmonary hypertension. Understanding the disease process as well as treatment outcome is an important factor for intraoperative management of those patients.

RECENT FINDINGS

Though offering many challenges, mild-to-moderate pulmonary hypertension and POPH patients could be transplanted safely. The most recently published studies describe the mortality of liver transplant patients with severe pulmonary hypertension and POPH to be 100%. The only available option might be a combined liver-lung transplant surgery, an option limited to very few centers.

SUMMARY

Publication on intraoperative anesthetic management of patient with pulmonary hypertension and POPH during liver transplant remains sparse. Management requires experience in cardiovascular anesthesia and utilization of knowledge, skills, medications, and tools learned in such cases. Further studies should be conducted on intraoperative use of inhaled and intravenous pulmonary vasodilators for its potential benefits during liver transplant surgery.