Right Heart Dimensions: Pushing the Yardstick beyond “One Size Fits All”

pp 473-474

Abstract

Identifying right ventricular (RV) dilation has implications for diagnosis and for prognosis. Linear dimensions obtained from the apical (basal and mid-RV dimension), parasternal long-axis [right ventricular outflow tract (RVOT)] and parasternal short axis (RVOT) are recommended to quantify RV size. (1) Ignoring the potential technical issues in quantifying RV dimensions, such as the complex RV geometry and limited visualization of the RV free wall and RV endocardium, quantifying RV dimensions remains a challenge for various reasons.
While the current non-indexed cut-off values are simple to use, one could question their diagnostic accuracy. Conceptually, it is plausible that the non-indexed values may inappropriately identify RV dilation in a healthy man with a body surface area (BSA) of 2.2 m2 and fail to identify RV dilation in a woman with an atrial septal defect and a BSA of 1.5 m2. Supporting this argument is the use of relative RV size as compared to the left ventricular (LV) size despite normal non-indexed RV linear dimensions.