Benza, Raymond L.

Background— Factors that determine survival in pulmonary arterial hypertension (PAH) drive clinical management. A quantitative survival prediction tool has not been established for research or clinical use. Methods and Results— Data from 2716 patients with PAH enrolled consecutively in the US Registry to Evaluate Early and Long-Term PAH Disease Management (REVEAL) were analyzed to assess predictors of 1-year survival. We identified independent prognosticators of survival and derived a multivariable, weighted risk formula for clinical use. One-year survival from the date of enrollment was 91.0% (95% confidence interval [CI], 89.9 to 92.1). In a multivariable analysis with Cox proportional hazards, variables independently associated with increased mortality included pulmonary vascular resistance >32 Wood units (hazard ratio [HR], 4.1; 95% CI, 2.0 to 8.3), PAH associated with portal hypertension (HR, 3.6; 95% CI, 2.4 to 5.4), modified New York Heart Association/World Health Organization functional class IV (HR, 3.1; 95% CI, 2.2 to 4.4), men >60 years of age (HR, 2.2; 95% CI, 1.6 to 3.0), and family history of PAH (HR, 2.2; 95% CI, 1.2 to 4.0). Renal insufficiency, PAH associated with connective tissue disease, functional class III, mean right atrial pressure, resting systolic blood pressure and heart rate, 6-minute walk distance, brain natriuretic peptide, percent predicted carbon monoxide diffusing capacity, and pericardial effusion on echocardiogram all predicted mortality. Based on these multivariable analyses, a prognostic equation was derived and validated by bootstrapping technique. Conclusions— We identified key predictors of survival based on the patient’s most recent evaluation and formulated a contemporary prognostic equation. Use of this tool may allow the individualization and optimization of therapeutic strategies. Serial follow-up and reassessment are warranted. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00370214.

Abstract Rationale Portopulmonary hypertension (PPHTN) occurs in 6% of liver transplant candidates. The pathogenesis of this complication of portal hypertension is poorly understood. Objectives To identify genetic risk factors for PPHTN in patients with advanced liver disease. Methods We performed a multicenter case-control study of patients with portal hypertension. Cases had a mean pulmonary artery pressure >25 mm Hg, pulmonary vascular resistance >240 dynes·s−1·cm−5, and pulmonary capillary wedge pressure ≤15 mm Hg. Controls had a right ventricular systolic pressure < 40 mm Hg (if estimated) and normal right-sided cardiac morphology by transthoracic echocardiography. We genotyped 1,079 common single nucleotide polymorphisms (SNPs) in 93 candidate genes in each patient. Measurements and Main Results The study sample included 31 cases and 104 controls. Twenty-nine SNPs in 15 candidate genes were associated with the risk of PPHTN (P < 0.05). Multiple SNPs in the genes coding for estrogen receptor 1, aromatase, phosphodiesterase 5, angiopoietin 1, and calcium binding protein A4 were associated with the risk of PPHTN. The biological relevance of one of the aromatase SNPs was supported by an association with plasma estradiol levels. Conclusions Genetic variation in estrogen signaling and cell growth regulators is associated with the risk of PPHTN. These biologic pathways may elucidate the mechanism for the development of PPHTN in certain patients with severe liver disease.