Comparison of magnetic resonance feature tracking for strain calculation with harmonic phase imaging analysis.

Objectives To compare a steady-state free precession cine sequence–based technique (feature tracking [FT]) to tagged harmonic phase (HARP) analysis for peak average circumferential myocardial strain (e cc ) analysis in a large and heterogeneous population of boys with Duchenne muscular dystrophy (DMD). Background Current e cc assessment techniques require cardiac magnetic resonance–tagged imaging sequences, and their analysis is complex. The FT method can readily be performed on standard cine (steady-state free precession) sequences. Methods We compared mid-left ventricular whole-slice e cc by the 2 techniques in 191 DMD patients grouped according to age and severity of cardiac dysfunction: group B: DMD patients 10 years and younger with normal ejection fraction (EF); group C: DMD patients older than 10 years with normal EF; group D: DMD patients older than 10 years with reduced EF but negative myocardial delayed enhancement (MDE); group E: DMD patients older than 10 years with reduced EF and positive MDE; and group A: 42 control subjects. Retrospective, offline analysis was performed on matched tagged and steady-state free precession slices. Results For the entire study population (N = 233), mean FT e cc values (−13.3 ± 3.8%) were highly correlated with HARP e cc values (−13.6 ± 3.4%), with a Pearson correlation coefficient of 0.899. The mean e cc of DMD patients determined by HARP (−12.52 ± 2.69%) and FT (−12.16 ± 3.12%) was not significantly different (p = NS). Similarly, the mean e cc of the control subjects by determined HARP (−18.85 ± 1.86) and FT (−18.81 ± 1.83) was not significantly different (p = NS). Excellent correlation between the 2 methods was found among subgroups A through E, except there was no significant difference in strain between groups B and C with FT analysis. Conclusions FT-based assessment of e cc correlates highly with e cc derived from tagged images in a large DMD patient population with a wide range of cardiac dysfunction and can be performed without additional imaging.