CMR RV size assessment should include RV to LV volume ratio

Background The right ventricular (RV) size responds to many cardiopulmonary diseases characterized by chronic pressure and volume overload. Cardiovascular magnetic resonance (CMR) is considered the “gold-standard” for RV evaluation. The RV end-diastolic volume indexed to body surface area (RVEDVi) has been used for RV size assessment, but this parameter alone may not be sensitive enough to detect RV dilation due to its wide normal range and the lack of consideration of individual heart size. We sought to determine if the assessment of right to left ventricular end-diastolic volume ratio (RVEDV/ LVEDV) in addition to RVEDVi increased the detection of RV dilation in the RV CMR analysis. The application of this ratio is investigated in a control and a Pulmonary Arterial Hypertension (PAH) population.