How low should we go? Potential benefits and ramifications of the pulmonary hypertension hemodynamic definitions proposed by the 6th World Symposium

Quantitative Proteomic and Phosphoproteomic Profiling of Lung Tissues from Pulmonary Arterial Hypertension Rat Model

Pulmonary arterial hypertension (PAH) is a rare but fatal disease characterized by elevated pulmonary vascular resistance and increased pressure in the distal pulmonary arteries. Systematic analysis of the proteins and pathways involved in the progression of PAH is crucial for understanding the underlying molecular mechanism. In this study, we performed tandem mass tags (TMT)-based relative quantitative proteomic profiling of lung tissues from rats treated with monocrotaline (MCT) for 1, 2, 3 and 4 weeks. A total of 6759 proteins were quantified, among which 2660 proteins exhibited significant changes (p-value < 0.05, fold change < 0.83 or >1.2). Notably, these changes included several known PAH-related proteins, such as Retnla (resistin-like alpha) and arginase-1. Furthermore, the expression of potential PAH-related proteins, including Aurora kinase B and Cyclin-A2, was verified via Western blot analysis. In addition, we performed quantitative phosphoproteomic analysis on the lungs from MCT-induced PAH rats and identified 1412 upregulated phosphopeptides and 390 downregulated phosphopeptides. Pathway enrichment analysis revealed significant involvement of pathways such as complement and coagulation cascades and the signaling pathway of vascular smooth muscle contraction. Overall, this comprehensive analysis of proteins and phosphoproteins involved in the development and progression of PAH in lung tissues provides valuable insights for the development of potential diagnostic and treatment targets for PAH.

Impact of borderline pulmonary hypertension due to left heart failure on mortality in a multicenter registry study: A 3-year survivorship analysis

Background

Patients with left heart failure (LHF) are often associated with the development of pulmonary hypertension (PH) which leads to an increased risk of death. Recently, the diagnostic standard for PH has changed from mean pulmonary arterial pressure (mPAP) ≥25 mmHg to >20 mmHg. Nonetheless, the effect of borderline PH (mPAP: 21–24 mmHg) on the prognosis of LHF patients is unclear. This study aimed to investigate the relationship between borderline PH and 3-year clinical outcomes in LHF patients.

Methods

A retrospective analysis of a prospective cohort study was done for LHF patients who underwent right heart catheterization (RHC) between January 2013 and November 2016. The primary outcome was all-cause mortality; the secondary outcome was rehospitalization.

Results

Among 344 patients, 62.5% were identified with a proportion of PH (mPAP ≥ 25), 10.8% with borderline PH (21–24), and 26.7% with non-PH (≤20), respectively. Multivariable Cox analysis revealed that borderline PH patients had a higher adjusted mortality risk (HR = 3.822; 95% CI: 1.043–13.999; p = 0.043) than non-PH patients. When mPAP was treated as a continuous variable, the hazard ratio for death increased progressively with increasing mPAP starting at 20 mmHg (HR = 1.006; 95% CI: 1.001–1.012). There was no statistically significant difference in adjusted rehospitalization between borderline PH and non-PH patients (HR = 1.599; 95% CI: 0.833–3.067; p = 0.158).

Conclusions

Borderline PH is independently related to increased 3-year mortality in LHF patients. Future research is needed to evaluate whether more close monitoring, and managing with an intensifier improves clinical outcomes in borderline PH caused by LHF.

Clinical trials registration

www.clinicaltrials.gov NCT02164526.

The definition of pulmonary hypertension: history, practical implications and current controversies

The definition of pulmonary hypertension (PH) is based on a growing body of evidence and represents the result of ongoing discussions within the PH community over the past 50 years. In 2018, the most recent World Symposium on Pulmonary Hypertension introduced significant changes in the definition of PH by lowering the mean pulmonary arterial pressure threshold to >20 mmHg and (re)introducing the pulmonary vascular resistance ≥3 WU cut-off for all forms of pre-capillary PH. These changes and their potential clinical impact have been the subject of lively discussions in the community and some important questions and controversies have been identified.

In this review we aim to present the development of the definition of PH over the past decades and discuss the main arguments that led to relevant modifications. In addition, we address the practical implications of the most recent changes and controversies that still exist.

The definitions of PH and PAH reflect the upper limit of normal haemodynamic values, their prognostic relevance and practical considerations. With appropriate clinical context they represent the cornerstone of PH diagnosis and clinical decision making.https://bit.ly/3gRSyWz