Cardiovascular magnetic resonance (CMR) is the reference modality for cardiac chamber quantification and is increasingly used to guide important clinical decisions. In order to understand how the heart changes with disease, we need to better define the healthy cardiovascular phenotype. Greater uniformity and accuracy in defining the boundaries of health and disease are key to optimising the clinical utility and universal cross-comparability of CMR.
While variations in cardiovascular phenotypes by sex, ethnicity, and age are well described, such population differences are not adequately addressed in existing CMR normal reference ranges. Technical sources of variation in CMR derived cardiovascular phenotypes arises, chiefly, from differences in segmentation methods and post-processing software. Heterogeneity in scanning and image analysis methods in existing reference ranges severely limits their cross comparability.
Figure 2. Different sources of variation in CMR metrics
There is urgent need for development of healthy CMR reference ranges with appropriate population stratifications to guide clinical practice and to allow global comparison of CMR measures.
To address these gaps in knowledge, we established the Healthy Hearts Consortium (HHC), an international collaborative which has resulted in the creation of a very large CMR databank of healthy adult hearts through collation of imaging data from published studies from around the world.