Right Ventricular Function Assessment Using CMR: a Radiologist's Perspective

Lynette Teo1, Ching Ching Ong1, Devinder Singh1, Choon Kuang Low2, Junda Song3, Ping Chai1
1National University Hospital, 2National Universiy Hospital, 3National University Hospi


Abnormalities of the right ventricle (RV) are common in congenital heart disease (CHD). The RV is exposed to volume overload in shunt lesions and in tricuspid and pulmonary valve regurgitation (eg, post-TOF repair). The RV is exposed to pressure overload eg. in pulmonary valve stenosis, large ventricular septal defect and tetralogy of Fallot (TOF). Cardiovascular magnetic resonance (CMR) is versatile and is not limited by acoustic window, body habitus or post-operative overlying scar tissue. It does not expose patients to ionizing radiation or morbidity associated with invasive diagnostic catheterization. The latest 2018 AHA/ACC Guidelines for the “Management of Adults With Congenital Heart Disease” states that “CMR plays a valuable role in assessment of RV size and function, because it provides data that are reproducible and more reliable than data obtained with alternative imaging techniques”. This data cements the role of CMR in guiding clinical decisions. RV volumes, stroke volume (SV), function (ejection fraction) and mass are obtained by segmentation / contouring of epicardial and endocardial borders in the short axis view using cine gradient echo images. This can be done by manual or semiautomated segmentation. It is more difficult to segment the RV compared to the LV given its increased trabeculations, inherent geometry and relations with pulmonary and tricuspid valves. The accuracy of segmentation can be correlated with left ventricle SV (assuming there are on shunts or significant regurgitation) and phase contrast imaging. This talk will focus on how RV parameters are obtained, the pitfalls in segmentation and how this data helps guide clinical decisions in common congenital heart conditions. Alternative modalities and the future forward will also be briefly discussed.