Pulmonary hypertension (PH) associated with left heart failure (LHF) (PH-LHF) is one of the most common causes of PH. It directly contributes to symptoms and reduced functional capacity and negatively affects right heart function, ultimately leading to a poor prognosis. There are no specific treatments for PH-LHF, despite the high number of drugs tested so far. This scientific document addresses the main knowledge gaps in PH-LHF with emphasis on pathophysiology and clinical trials. Key identified issues include better understanding of the role of pulmonary venous versus arteriolar remodelling, multidimensional phenotyping to recognize patient subgroups positioned to respond to different therapies, and conduct of rigorous pre-clinical studies combining small and large animal models. Advancements in these areas are expected to better inform the design of clinical trials and extend treatment options beyond those effective in pulmonary arterial hypertension. Enrichment strategies, endpoint assessments, and thorough haemodynamic studies, both at rest and during exercise, are proposed to play primary roles to optimize early-stage development of candidate therapies for PH-LHF.

• Keywords
• Drug, Heart failure, Pulmonary hypertension, Therapy, Translational,
• MeSH
• Ventricular Function, Right * physiology   MeSH
• Humans MeSH
• Hypertension, Pulmonary * physiopathology   etiology   therapy   MeSH
• Pulmonary Circulation * physiology   MeSH
• Heart Failure * physiopathology   complications   therapy   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH

OBJECTIVES: The authors hypothesized that quantitative computed tomography (QCT) imaging would reveal subclinical increases in lung congestion in patients with heart failure and preserved ejection fraction (HFpEF) and that this would be related to pulmonary vascular hemodynamic abnormalities. BACKGROUND: Gross evidence of lung congestion on physical examination, laboratory tests, and radiography is typically absent among compensated ambulatory patients with HFpEF. However, pulmonary gas transfer abnormalities are commonly observed and associated with poor outcomes. METHODS: Patients referred for invasive hemodynamic exercise testing who had undergone chest computed tomography imaging within 1 month were identified (N = 137). A novel artificial intelligence QCT algorithm was used to measure pulmonary fluid content. RESULTS: Compared with control subjects with noncardiac dyspnea, patients with HFpEF displayed increased mean lung density (-758 HU [-793, -709 HU] vs -787 HU [-828, -747 HU]; P = 0.002) and a higher ratio of extravascular lung water to total lung volume (EVLWV/TLV) (1.25 [0.80, 1.76] vs 0.66 [0.01, 1.03]; P < 0.0001) by QCT imaging, indicating greater lung congestion. EVLWV/TLV was directly correlated with pulmonary vascular pressures at rest, with stronger correlations observed during exercise. Patients with increasing tertiles of EVLWV/TLV demonstrated higher mean pulmonary artery pressures at rest (34 ± 11 mm Hg vs 39 ± 14 mm Hg vs 45 ± 17 mm Hg; P = 0.0003) and during exercise (55 ± 17 mm Hg vs 59 ± 17 mm Hg vs 69 ± 22 mm Hg; P = 0.0003). CONCLUSIONS: QCT imaging identifies subclinical lung congestion in HFpEF that is not clinically apparent but is related to abnormalities in pulmonary vascular hemodynamics. These data provide new insight into the long-term effects of altered hemodynamics on pulmonary structure and function in HFpEF.

• Keywords
• computed tomography, congestion, exercise, heart failure, hemodynamics,
• MeSH
• Hemodynamics MeSH
• Humans MeSH
• Lung diagnostic imaging   MeSH
• Pulmonary Edema * diagnostic imaging   etiology   MeSH
• Predictive Value of Tests MeSH
• Heart Failure * complications   diagnostic imaging   MeSH
• Stroke Volume MeSH
• Artificial Intelligence MeSH
• Exercise Test MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, N.I.H., Extramural MeSH