Right Ventricular Dysfunction in Lung Disease/Hypoxia-Associated Pulmonary Hypertension

Area of Science:

• Cardiology
• Pulmonology
• Medical Imaging

Background:

• Limited data exist on right ventricular (RV) function in lung disease/hypoxia-associated pulmonary hypertension (PH).
• Understanding RV dysfunction is crucial for managing PH associated with lung disease.

Purpose of the Study:

• To clarify the presence, characteristics, and clinical significance of RV dysfunction in patients with lung disease/hypoxia-associated PH.
• To compare RV function in patients with lung disease/hypoxia-associated PH, no PH, and pulmonary arterial hypertension (PAH).

Main Methods:

• Cardiac magnetic resonance imaging (CMR) assessed RV volume.
• Right heart catheterization and dedicated software analyzed RV pressure data.
• RV contractility (Ees), diastolic function (β, end-diastolic elastance), and RV-pulmonary artery coupling (Ees/arterial elastance) were evaluated.

Main Results:

• In lung disease/hypoxia-associated PH, RV contractility (Ees) was preserved, but diastolic function (β, end-diastolic elastance) was impaired, and RV-pulmonary artery coupling (Ees/arterial elastance) was reduced compared to controls.
• No significant differences in these RV function parameters were observed between lung disease/hypoxia-associated PH and PAH groups.
• RV-pulmonary artery coupling correlated with 6-minute walk distance and mortality in PAH, but not in lung disease/hypoxia-associated PH. Pulmonary vasodilator therapy improved RV function in PAH, but not in lung disease/hypoxia-associated PH.

Conclusions:

• RV contractility is preserved in lung disease/hypoxia-associated PH, while diastolic function and RV-pulmonary artery coupling are impaired.
• The clinical relevance of RV dysfunction in lung disease/hypoxia-associated PH requires further investigation.
• Distinct mechanisms and therapeutic responses may exist for RV dysfunction in different PH subtypes.