Age- and sex-differences and reference values for ventricular strain by cardiovascular magnetic resonance imaging in adults without cardiovascular disease or cardiovascular disease risk factors.

Background: Myocardial deformation measured by myocardial strain is an important marker of cardiovascular disease (CVD). We aimed to establish normal values and examine age- and sex-differences in left and right ventricular (LV, RV) strain using feature tracking cardiovascular resonance (FT-CMR) in adults free of CVD in the community.

Methods: Framingham Heart Study Offspring participants without CVD, hypertension, or diabetes completed CMR (1.5T) (n=903, 59% (533/903) women, 36-88 years of age). Global longitudinal, circumferential, and radial strain (GLS, GCS, and GRS, respectively) were measured by semi-automated LV and RV myocardial segmentation of short-axis, 2-chamber, and 4-chamber images with cvi42 (v.5.13, Circle Cardiovascular Imaging, Calgary, Canada).

Results: Mean LV GLS, GCS, and GRS were -17.8±2.5%, -19.7±2.4%, and 34.9±6.9%, respectively; RV GLS, GCS, and GRS were -20.4±4.0%, -11.7±3.5%, and 19.1±6.5%, respectively. All strain values were of greater magnitude in women than men (all p<0.005). LV and RV GCS and GRS were of greater magnitude (more negative and more positive, respectively) with increasing age (all p<0.001), but GLS was not associated with age. Stratified analysis by sex showed LV and RV GCS and GRS were greater in magnitude with increasing age in women (all p<0.001), whereas no age associations in men were observed.

Conclusion: We provide FT-CMR reference values for LV and RV strain in a large, community-dwelling U.S. adult cohort free of CVD and CVD risk factors. Women demonstrated greater magnitude LV and RV GCS and GRS with increasing age. The clinical implications of sex-differences in ventricular strain and mechanical remodeling with age deserve further study.