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

Abstract

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.

Keywords: Cardiovascular magnetic resonance; Feature tracking; Ventricular strain.

Graphical abstract

Fig. 1

Endocardial (red) and epicardial (green) border segmentation for FT-strain analysis. LV and RV endocardial and epicardial contours in 2Ch (top left), 4Ch (bottom left), and SAx (right) views. FT feature tracking, LV left ventricle, RV right ventricle, 2Ch two chamber, 4Ch four chamber, SAx short axis

Fig. 2

Deformation of myocardial endocardial (red) and epicardial (green) border tags at end-systole. Movement of tags and tracking of myocardial strain in 2Ch, 4Ch, and SAx images are shown. 2Ch two chamber, 4Ch four chamber, SAx short axis

Fig. 3

FT-CMR color maps and graphs of GLS, GCS, and GRS (left-right). Top panel: 17-segment model color overlay map of GLS, GCS, GRS, respectively shown left to right. Bottom panel: corresponding GLS, GCS, and GRS strain curves. GLS global longitudinal strain, GCS global circumferential strain, GRS global radial strain

Fig. 4

Left and right ventricular strain across age groups. Boxplots of global strain values across age groups. Brackets indicate significant pairwise comparisons (p<0.0083; †: p<0.005; *: p<0.0001). LV left ventricle, RV right ventricle, GLS global longitudinal strain, GCS global circumferential strain, GRS global radial strain

Fig. 5

Left and right ventricular strain by sex. Boxplots of global strain values for men and women. All comparisons between sexes were statistically significant (p<0.0083). LV, left ventricle, RV right ventricle, GLS global longitudinal strain, GCS global circumferential strain, GRS global radial strain

Fig. 6

Left and right ventricular strain across age groups and by sex. Boxplots of global strain values across age groups for men (blue) and women (red). Brackets indicate significant pairwise comparisons (p<0.0083; †: p<0.005; *: p<0.0001). LV left ventricle, RV right ventricle, GLS global longitudinal strain, GCS global circumferential strain, GRS global radial strain