Kawut, Steven M.

Portopulmonary hypertension (POPH), pulmonary arterial hypertension that develops in the setting of portal hypertension, has long been of significant interest to the pulmonary, cardiology, and hepatology communities. Optimal management of POPH has been challenging to define due to a lack of evidence from clinical trials regarding pulmonary arterial hypertension therapies and uncertainty regarding the role of liver transplantation (LT). Initially, the high risk of intraoperative and early post-transplant death in predominantly untreated patients with POPH tempered consideration of LT. More recently, the observation that POPH can improve, and sometimes even resolve, following LT, has led to reconsideration of the role of LT in selected patients. The first International Liver Transplantation Society (ILTS) POPH and hepatopulmonary syndrome practice guideline was a multidisciplinary consensus of expert opinions based on available evidence. Since that publication, hemodynamic definitions, management approaches, and POPH MELD exception criteria have evolved, and there have been new randomized controlled trials in POPH as well as studies regarding long-term outcomes. In order to ensure the guidelines remained current and reflected recent evidence, the original writing committee of the 2016 guidelines, leaders of the ILTS Cardiovascular Special Interest Group, and colleagues active in POPH research were invited to participate in the writing committee. In this document, approved for publication by the ILTS executive council, we provide an update to the prior guidelines with expert recommendations to guide and advance POPH management. Recommendations in these guidelines are based on expert opinion and available evidence and were agreed upon by consensus.

Patients with chronic liver disease commonly have abnormal lung function; however, the impact of smoking on outcomes in these patients is unknown. We hypothesized current or past smoking would be associated with worse survival in patients with advanced liver disease. The Pulmonary Vascular Complications in Liver Disease Study 2 (PVCLD2) was a prospective cohort of patients with advanced liver disease undergoing evaluation for liver transplantation (LT). Patients were classified by self-report as a “non-smoker,” “past smoker,” or “current smoker.” We used Cox proportional hazards models and Fine-Gray models with LT as a competing risk. Models were adjusted for age, sex, body mass index, race, family income, liver disease etiology, and Model for End-Stage Liver Disease-Sodium score. Of the 410 patients included, most (65%) were male and the mean age at enrollment was 56.5 years. One hundred sixty (39%) patients were nonsmokers, 183 (45%) were past smokers, and 67 (16%) were current smokers. In total, 151 (37%) patients received an LT, and 88 (20%) patients died. When compared to nonsmokers, current smokers had a 2.17-fold increase in risk of death overall (95% CI: 1.12–4.18, p = 0.02). There was a 7% increase in overall risk of death for every 5 pack-years increase (95% CI: 1.01–1.13, p = 0.02). With LT as a competing risk, the subdistributional HR of current smokers versus nonsmokers for death was 2.45 (95% CI: 1.31–4.60, p = 0.005). In this model, past smokers displayed a nonsignificant increase in the risk of death compared to nonsmokers (subdistributional HR: 1.58, 95% CI: 0.91–2.72, p = 0.10). Patients with advanced liver disease undergoing evaluation for LT who smoke have an increased risk of death. Smoking cessation could lead to improved overall survival with or without LT.

Abstract Rationale Inhibition of aromatase with anastrozole reduces pulmonary hypertension in experimental models. Objectives We aimed to determine whether anastrozole improved the 6-minute-walk distance (6MWD) at 6 months in pulmonary arterial hypertension (PAH). Methods We performed a randomized, double-blind, placebo-controlled phase II clinical trial of anastrozole in subjects with PAH at seven centers. Eighty-four postmenopausal women with PAH and men with PAH were randomized in a 1:1 ratio to receive anastrozole 1 mg or placebo by mouth daily, stratified by sex using permuted blocks of variable sizes. All subjects and study staff were masked. The primary outcome was the change from baseline in 6MWD at 6 months. By intention-to-treat analysis, we estimated the treatment effect of anastrozole using linear regression models adjusted for sex and baseline 6MWD. Assuming 10% loss to follow-up, we anticipated having 80% power to detect a difference in the change in 6MWD of 22 meters. Measurements and Main Results Forty-one subjects were randomized to placebo and 43 to anastrozole, and all received the allocated treatment. Three subjects in the placebo group and two in the anastrozole group discontinued the study drug. There was no significant difference in the change in 6MWD at 6 months (placebo-corrected treatment effect, −7.9 m; 95% confidence interval, −32.7 to 16.9; P = 0.53). There was no difference in adverse events between the groups. Conclusions Anastrozole did not show a significant effect on 6MWD compared with placebo in postmenopausal women with PAH and in men with PAH. Anastrozole was safe and did not have adverse effects. Clinical trial registered with www.clincialtrials.gov (NCT03229499).

Background and Aims: Hepatopulmonary syndrome (HPS) and a hyperdynamic circulation are common complications of advanced liver disease, but the relationship between HPS and cardiac index (CI) is poorly understood. We sought to compare CI in patients with and without HPS and to assess the relationship between CI and symptoms, quality of life, gas exchange, and exercise capacity among liver transplantation (LT) candidates. We performed a cross-sectional analysis within the Pulmonary Vascular Complications of Liver Disease 2 study, a multicenter prospective cohort study of patients being evaluated for LT. We excluded patients with obstructive or restrictive lung disease, intracardiac shunting, and portopulmonary hypertension. We included 214 patients (81 with HPS and 133 controls without HPS). Compared with controls, patients with HPS had a higher CI (least square mean 3.2 L/min/m2, 95% CI 3.1–3.4 vs. 2.8 L/min/m2, 95% CI 2.7–3.0, p < 0.001) after adjustment for age, sex, Model for End-stage Liver Disease-Sodium (MELD-Na) score and beta-blocker use, and a lower systemic vascular resistance. Among all LT candidates, CI was correlated with oxygenation (Alveolar-arterial oxygen gradient r=0.27, p< 0.001), intrapulmonary vasodilatation severity (p < 0.001), and biomarkers of angiogenesis. Higher CI was independently associated with dyspnea and worse functional class and physical quality of life after adjusting for age, sex, MELD-Na, beta-blocker use, and HPS status. HPS was associated with a higher CI among LT candidates. Independent of HPS, higher CI was associated with increased dyspnea and worse functional class, quality of life, and arterial oxygenation.

A 6-minute walk test is a simple tool for assessing submaximal exercise capacity. We sought to determine whether a 6-minute walk distance (6MWD) predicts outcomes in patients with cirrhosis. The Pulmonary Vascular Complications of Liver Disease 2 study is a multicenter, prospective cohort study that enrolled adults with portal hypertension during liver transplantation evaluation. We excluded subjects with an incident or prevalent portopulmonary hypertension. The 6-minute walk test was performed using standardized methods. Cox proportional hazards modeling and multivariable linear regression analysis were performed to determine the relationship between baseline 6MWD and outcomes. The study sample included 352 subjects. The mean 6MWD was 391±101 m. For each 50-meter decrease in 6MWD, there was a 25% increase in the risk of death (HR 1.25, 95% CI [1.11, 1.41], p < 0.001) after adjustment for age, gender, body mass index, MELD-Na, and liver transplant as a time-varying covariate. In a multistate model, each 50-meter decrease in 6MWD was associated with an increased risk of death before the liver transplant ( p < 0.001) but not after the transplant. 6MWD was similar to MELD-Na in discriminating mortality. Each 50-meter decrease in 6MWD was associated with an increase in all-cause ( p < 0.001) and transplant-free hospitalizations ( p < 0.001) in multivariable models for time-to-recurrent events. Shorter 6MWD was associated with worse Short Form-36 physical ( p < 0.001) and mental component scores ( p = 0.05). In conclusion, shorter 6MWD is associated with an increased risk of death, hospitalizations, and worse quality of life in patients evaluated for liver transplantation. The 6-minute walk distance may be a useful adjunct for risk assessment in patients undergoing liver transplant evaluation.

Background Current mortality data for pulmonary arterial hypertension (PAH) in the United States are based on registries that enrolled patients prior to 2010. We sought to determine mortality in PAH in the modern era using the PHAR (Pulmonary Hypertension Association Registry). Methods and Results We identified all adult patients with PAH enrolled in the PHAR between September 2015 and September 2020 (N=935). We used Kaplan‐Meier survival analysis and Cox proportional hazards models to assess mortality at 1, 2, and 3 years. Patients were stratified based on disease severity by 3 validated risk scores. In treatment‐naïve patients, we compared survival based on initial treatment strategy. The median age was 56 years (44–68 years), and 76% were women. Of the 935 patients, 483 (52%) were ≤6 months from PAH diagnosis. There were 121 deaths (12.9%) during a median follow‐up time of 489 days (281–812 days). The 1‐, 2‐, and 3‐year mortality was 8% (95% CI, 6%–10%), 16% (95% CI, 13%–19%), and 21% (95% CI, 17%–25%), respectively. When stratified into low‐, intermediate‐, and high‐risk PAH, the mortality at 1, 2, and 3 years was 1%, 4% to 6%, and 7% to 11% for low risk; 7% to 8%, 11% to 16%, and 18% to 20% for intermediate risk; and 12% to 19%, 22% to 38%, and 28% to 55% for high risk, respectively. In treatment‐naïve patients, initial combination therapy was associated with better 1‐year survival (adjusted hazard ratio, 0.43 [95% CI, 0.19–0.95]; P =0.037). Conclusions Mortality in the intermediate‐ and high‐risk patients with PAH remains unacceptably high in the PHAR, suggesting the importance for early diagnosis, aggressive use of available therapies, and the need for better therapeutics.

Abstract Rationale Single-center studies demonstrated that methamphetamine use is associated with pulmonary arterial hypertension (Meth-APAH). We used the Pulmonary Hypertension Association Registry to evaluate the national distribution of Meth-APAH and to compare its impact on patient-reported and clinical outcomes relative to idiopathic PAH. Objectives To determine if patients with Meth-APAH differ from those with idiopathic PAH in demographics, regional distribution in the United States, hemodynamics, health-related quality of life, PAH-specific treatment, and health care use. Methods The Pulmonary Hypertension Association Registry is a U.S.-based prospective cohort of patients new to care at a Pulmonary Hypertension Care Center. The registry collects baseline demographics, clinical parameters, and repeated measures of health-related quality of life, World Health Organization functional class, 6-minute walk distance, therapy, and health care use. Repeated measures of functional class, health-related quality of life, type of therapy, emergency department visits, and hospitalizations were compared using generalized estimating equations. Results Of 541 participants included, 118 had Meth-APAH; 83% of Meth-APAH arose in the western United States. The Meth-APAH group was younger and had a poorer socioeconomic status and lower cardiac index than the idiopathic PAH group, despite no difference in mean pulmonary artery pressure or pulmonary vascular resistance. The Meth-APAH group had a more advanced functional class in longitudinal models (0.22 points greater; 95% confidence interval [CI], 0.07 to 0.37) and worse PAH-specific (emPHasis-10) health-related quality of life (−5.4; 95% CI, −8.1 to −2.8). There was no difference in dual combination therapy; however, participants with Meth-APAH were less likely to be initiated on triple therapy (odds ratio [OR], 0.43; 95% CI, 0.24 to 0.77) or parenteral therapy (OR, 0.10; 95% CI, 0.04 to 0.24). Participants with Meth-APAH were more likely to seek care in the emergency department (incidence rate ratio, 2.30; 95% CI, 1.71 to 3.11) and more likely to be hospitalized (incidence rate ratio, 1.42; 95% CI, 1.10 to 1.83). Conclusions Meth-APAH represents a unique clinical phenotype of PAH, most common in the western United States. It accounts for a notable proportion of PAH in expert centers. Assessment for methamphetamine use is necessary in patients with PAH.