Porto-pulmonary arterial hypertension: Translation of pathophysiological concepts to the bedside

Porto-Sinusoidal Vascular Disease and Downhill Varices: Separate Clinical Entities?

Introduction

Porto-sinusoidal vascular disease (PSVD) is an entity characterized by the absence of histologic liver cirrhosis and the detection of specific or non-specific histological findings, irrespective of the presence of portal hypertension (PHT). The pathogenesis remains poorly understood. Pulmonary arterial hypertension (PAH), independently of the presence of PHT, can be associated with an increase in central venous pressure, which can rarely lead to the development of downhill varices in the proximal esophagus.

Case Presentation

A 53-year-old woman, with an unremarkable medical and pharmacological history, presented with a 3-day history of melena, epigastric pain and hematemesis. Physical examination revealed bilateral peripheral edema of the legs. Laboratory findings included severe anemia, normal hepatic enzymology, and NT-proBNP 1,748 pg/mL. Endoscopy showed large proximal esophageal varices and mild hypertensive gastropathy. A complete liver disease etiology panel was negative. Ultrasound showed an irregular liver surface, splenomegaly, and dilated supra-hepatic veins and inferior vena cava. Echocardiogram revealed significant cardiac valve and cavity abnormalities, especially on the right side, as well as moderate to severe PAH. Diuretics therapy was started with clinical improvement. Beta-blockers were suspended due to intolerance. There were no images suggestive of portosystemic collateralization on angiography. Re-evaluation endoscopy showed large but reduced esophageal varices, without red spots. Cardiopulmonary hemodynamic assessment revealed moderate PAH (40 mm Hg). Liver hemodynamic study revealed non-clinically significant sinusoidal PHT. Transjugular liver biopsy revealed nodular regenerative hyperplasia suggestive of PSVD.

Discussion/Conclusion

The case was complex and presented diagnostic challenges, illustrating the uncommonly reported association between PSVD and porto-pulmonary hypertension and the importance of the transjugular liver biopsy and pressure measurements to confirm both diagnoses.

Advanced hemodynamic and cluster analysis for identifying novel RV function subphenotypes in patients with pulmonary hypertension

BACKGROUND

Quantifying right ventricular (RV) function is important to describe the pathophysiology of in pulmonary hypertension (PH). Current phenotyping strategies in PH rely on few invasive hemodynamic parameters to quantify RV dysfunction severity. The aim of this study was to identify novel RV phenotypes using unsupervised clustering methods on advanced hemodynamic features of RV function.

METHODS

Participants were identified from the University of Arizona Pulmonary Hypertension Registry (n = 190). RV-pulmonary artery coupling (Ees/Ea), RV systolic (Ees), and diastolic function (Eed) were quantified from stored RV pressure waveforms. Consensus clustering analysis with bootstrapping was used to identify the optimal clustering method. Pearson correlation analysis was used to reduce collinearity between variables. RV cluster subphenotypes were characterized using clinical data and compared to pulmonary vascular resistance (PVR) quintiles.

RESULTS

Five distinct RV clusters (C1-C5) with distinct RV subphenotypes were identified using k-medoids with a Pearson distance matrix. Clusters 1 and 2 both have low diastolic stiffness (Eed) and afterload (Ea) but RV-PA coupling (Ees/Ea) is decreased in C2. Intermediate cluster (C3) has a similar Ees/Ea as C2 but with higher PA pressure and afterload. Clusters C4 and C5 have increased Eed and Ea but C5 has a significant decrease in Ees/Ea. Cardiac output was high in C3 distinct from the other clusters. In the PVR quintiles, contractility increased and stroke volume decreased as a function of increased afterload. World Symposium PH classifications were distributed across clusters and PVR quintiles.

CONCLUSIONS

RV-centric phenotyping offers an opportunity for a more precise-medicine-based management approach.

Pulmonary Arterial Hypertension in Genetic and Comorbid Settings: A Step Forward for Precision Medicine

The editorial refers to the Special Issue "Pulmonary Arterial Hypertension: Old Drugs and New Treatment Strategies" [...].