Right ventricular and right atrial dilatation phenotypes in pulmonary arterial hypertension

<title>Extract</title> Pulmonary arterial hypertension (PAH) is characterized by increased pulmonary vascular resistance and afterload on the right heart. The degree of right ventricular (RV) adaptation determines exercise capacity and prognosis[1]. RV dilatation and RV-pulmonary artery coupling parameters show prognostic value in addition to current risk stratification tools[2]. Right atrial function also contributes to PAH risk assessment since RA pressure and volume are associated with mortality[3, 4]. Previously, we have shown that the right atrium is more severely dilated than the ventricle in patients with severe RV diastolic stiffness[5, 6]. However, the RV end-diastolic volume (EDV) was not different in patients with or without severe RV diastolic stiffness. Therefore, the aim of this study was to gain a deeper understanding of the clinical and prognostic significance of RV and RA dilatation phenotypes in PAH.