Myocardial strain measurement with feature-tracking cardiovascular magnetic resonance: normal values

Aims Myocardial deformation is a key to clinical decision-making. Feature-tracking cardiovascular magnetic resonance (FT-CMR) provides quantification of motion and strain using standard steady-state in free-precession (SSFP) imaging, which is part of a routine CMR left ventricular (LV) study protocol. An accepted definition of a normal range is essential if this technique is to enter the clinical arena. Methods and results One hundred healthy individuals, with 10 men and women in each of 5 age deciles from 20 to 70 years, without a history of cardiovascular disease, diabetes, renal impairment, or family history of cardiovascular disease, and with a normal stress echocardiogram, underwent FT-CMR assessment of LV myocardial strain and strain rate using SSFP cines. Peak systolic longitudinal strain (E-ll) was -21.3 +/- 4.8%, peak systolic circumferential strain (E-cc) was -26.1 +/- 3.8%, and peak systolic radial strain (E-rr) was 39.8 +/- 8.3%. On Bland-Altman analyses, peak systolic E-cc had the best inter-observer agreement (bias 0.63 +/- 1.29% and 95% CI - 1.90 to 3.16) and peak systolic E-rr the least inter-observer agreement (bias 0.13 +/- 6.41 and 95% CI - 12.44 to 12.71). Therewas an increase in the magnitude of peak systolic E-cc with advancing age, which was greatest in subjects over the age of 50 years (R-2 = 0.11, P = 0.003). There were significant gender differences (P < 0.001) in peak systolic E-ll, with a greater magnitude of deformation in females (222.7%) than in males (219.3%). Conclusion Normal values for myocardial strain measurements using FT-CMR are provided. All circumferential and longitudinal based variables had excellent intra-and inter-observer variability.