Abstract
Introduction: Idiopathic pulmonary arterial hypertension (iPAH) is a fatal disease with grim prognosis due to subsequent development of right heart failure (RHF). Findings in experimental pulmonary hypertension models suggest RHF is associated with increased diastolic stiffness.
Objective: This study investigates whether right ventricle (RV) diastolic stiffness is increased in iPAH patients.
Methods: Right heart catheterization (RHC) and MRI were performed in 28 patients suspected with iPAH. Based on pulmonary artery pressure, patients were divided into controls (7) and iPAH (21). Diastolic elastance (diastolic stiffness), was quantified by the slope of diastolic pressure-volume relation, constructed by plotting RV end-systolic volumes and begin-diastolic pressures against RV end-diastolic volumes and end-diastolic pressures. Subsequently, we investigated whether diastolic elastance was associated with disease severity by comparing patients with lower RV stoke volumes (RVSV) and patients with higher RVSV.
Results: Diastolic elastance was significantly altered in iPAH (iPAH 0.25±0.04 vs. Con 0.07±0.006, p=0.024). In addition, patients with lower RVSV had significantly higher diastolic elastance (LowSV0.38±0.05 vs HighSV 0.114±0.02).
Conclusion: This study demonstrates that RV diastolic stiffness is increased in iPAH-patients and is associated with disease severity. In future studies we will investigate the prognostic relevance of these changes.
- © 2011 ERS
