Inter-study reproducibility of left ventricular torsion and torsion rate quantification using MR myocardial feature tracking

J Magn Reson Imaging. 2016 Jan;43(1):128-37. doi: 10.1002/jmri.24979. Epub 2015 Jun 26.

Abstract

Background: To determine the inter-study reproducibility of MR feature tracking (MR-FT) derived left ventricular (LV) torsion and torsion rates for a combined assessment of systolic and diastolic myocardial function.

Methods: Steady-state free precession (SSFP) cine LV short-axis stacks were acquired at 9:00 (Exam A), 9:30 (Exam B), and 14:00 (Exam C) in 16 healthy volunteers at 3 Tesla. SSFP images were analyzed offline using MR-FT to assess rotational displacement in apical and basal slices. Global peak torsion, peak systolic and peak diastolic torsion rates were calculated using different definitions ("twist", "normalized twist" and "circumferential-longitudinal (CL) shear angle"). Exam A and B were compared to assess the inter-study reproducibility. Morning and afternoon scans were compared to address possible diurnal variation.

Results: The different methods showed good inter-study reproducibility for global peak torsion (intraclass correlation coefficient [ICC]: 0.90-0.92; coefficient of variation [CoV]: 19.0-20.3%) and global peak systolic torsion rate (ICC: 0.82-0.84; CoV: 25.9-29.0%). Conversely, global peak diastolic torsion rate showed little inter-study reproducibility (ICC: 0.34-0.47; CoV: 40.8-45.5%). Global peak torsion as determined by the CL shear angle showed the best inter-study reproducibility (ICC: 0.90;CoV: 19.0%). MR-FT results were not measurably affected by diurnal variation between morning and afternoon scans (CL shear angle: 4.8 ± 1.4°, 4.8 ± 1.5°, and 4.1 ± 1.6° for Exam A, B, and C, respectively; P = 0.21).

Conclusion: MR-FT based derivation of myocardial peak torsion and peak systolic torsion rate has high inter-study reproducibility as opposed to peak diastolic torsion rate. The CL shear angle was the most reproducible parameter independently of cardiac anatomy and may develop into a robust tool to quantify cardiac rotational mechanics in longitudinal MR-FT patient studies.

Keywords: cardiovascular magnetic resonance; circumferential longitudinal shear angle; feature tracking; inter-study reproducibility; torsion; twist.

Publication types

  • Comparative Study
  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Female
  • Humans
  • Image Interpretation, Computer-Assisted / methods*
  • Male
  • Observer Variation
  • Pattern Recognition, Automated / methods*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Torsion Abnormality / pathology*
  • Ventricular Dysfunction, Left / pathology*