title: The consistency of myocardial strain derived from heart deformation analysis.
abstract: The purpose of this study was to assess the consistency of semi-automated myocardial strain analysis by prototype software across field strengths, temporal resolutions, and examinations. 35 volunteers (48 ± 13 years; 20% women) and 25 patients (54 ± 12 years; 44% women) without significant cardiac dysfunction underwent cine cardiac magnetic resonance imaging (CMR) at 1.5 T with a temporal resolution of 39.2 msec. 34 subjects also underwent imaging at 3.0 T; 16 had repeat examinations within 14 days; and 9 underwent CMR with temporal resolutions of 12.5 and 39.2 msec on the same day. Prototype heart deformation analysis (HDA) software was used to retrospectively quantify strain from segmented balanced steady state free precession (bSSFP) cinegraphic images. Myocardial contours were automatically generated on short axis images and drawn at end-diastole by two independent reviewers on long-axis images. Contours were automatically propagated throughout the cardiac cycle. Global and regional peak systolic strain were compared across observers, field strengths, temporal resolutions, and examinations. Inter-observer agreement was excellent (ICC > 0.87, p < 0.01). Inter-examination variability was low, ranging from 1.7 (1.0-2.4)% to 2.5 (1.9-3.1)%, except for radial strain: 9.2 (7.6-10.5)%. Most global and regional strain values were not significantly different across field strengths and temporal resolutions (p > 0.05). Normal global peak systolic strain values with HDA were -25.0 (-24.0 to -26.1)% (LV circumferential), 60.5 (55.3 to 65.6)% (LV radial), -22.3 (-20.5 to - 24.0)% (LV longitudinal), and -26.0 (-23.8 to -28.2)% (RV longitudinal). HDA prototype software enabled efficient and consistent quantification of myocardial strain from conventional bSSFP cine CMR data, demonstrating clinical feasibility.
authors.affiliation: Department of Radiology, Feinberg School of Medicine, Northwestern University, 737 N. Michigan Ave Suite 1600, Chicago, IL, USA.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Keller
authors.affiliation: Department of Radiology, Feinberg School of Medicine, Northwestern University, 737 N. Michigan Ave Suite 1600, Chicago, IL, USA.
authors.forename: Shanna
authors.initials: S
authors.lastname: Fang
authors.affiliation: Department of Radiology, Feinberg School of Medicine, Northwestern University, 737 N. Michigan Ave Suite 1600, Chicago, IL, USA.
authors.forename: Kai
authors.initials: K
authors.lastname: Lin
authors.affiliation: Department of Cardiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
authors.forename: Benjamin H
authors.initials: BH
authors.lastname: Freed
authors.affiliation: Department of Radiology, Feinberg School of Medicine, Northwestern University, 737 N. Michigan Ave Suite 1600, Chicago, IL, USA.
authors.forename: Peter M
authors.initials: PM
authors.lastname: Smith
authors.affiliation: Cardiovascular MR R&D, Siemens Healthcare, Chicago, IL, USA.
authors.forename: Bruce S
authors.initials: BS
authors.lastname: Spottiswoode
authors.affiliation: Department of Radiology, Feinberg School of Medicine, Northwestern University, 737 N. Michigan Ave Suite 1600, Chicago, IL, USA.
authors.forename: Rachel
authors.initials: R
authors.lastname: Davids
authors.affiliation: Department of Radiology, Feinberg School of Medicine, Northwestern University, 737 N. Michigan Ave Suite 1600, Chicago, IL, USA.
authors.forename: Maria
authors.initials: M
authors.lastname: Carr
authors.affiliation: Medical Imaging Technologies, Siemens Healthcare, Princeton, NJ, USA.
authors.forename: Marie-Pierre
authors.initials: MP
authors.lastname: Jolly
authors.affiliation: Department of Radiology, Feinberg School of Medicine, Northwestern University, 737 N. Michigan Ave Suite 1600, Chicago, IL, USA.|Department of Biomedical Engineering, Northwestern University, Evanston, IL, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Markl
authors.affiliation: Department of Radiology, Feinberg School of Medicine, Northwestern University, 737 N. Michigan Ave Suite 1600, Chicago, IL, USA.
authors.forename: James C
authors.initials: JC
authors.lastname: Carr
authors.affiliation: Department of Radiology, Feinberg School of Medicine, Northwestern University, 737 N. Michigan Ave Suite 1600, Chicago, IL, USA. collins@fsm.northwestern.edu.
authors.forename: Jeremy D
authors.initials: JD
authors.lastname: Collins
mesh_terms: D000328:Adult; D000368:Aged; D001331:Automation; D001696:Biomechanical Phenomena; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D015588:Observer Variation; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012984:Software; D013314:Stress, Mechanical; D013318:Stroke Volume; D013997:Time Factors; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000503:physiopathology; D016277:Ventricular Function, Left
keywords: Consistency; Field strength; Heart deformation analysis; Myocardial strain; Temporal resolution