Author + information
- Received September 29, 2016
- Revision received December 6, 2016
- Accepted December 9, 2016
- Published online February 5, 2018.
- aMenzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia
- bBaker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia
- ↵∗Address for correspondence:
Dr. Kazuaki Negishi, Menzies Institute for Medical Research, University of Tasmania, 17 Liverpool Street, Private Bag 23, Hobart, 7000, Australia.
Objectives The aim of this study was to perform a systematic review and meta-analysis to estimate the normal ranges of magnetic resonance imaging (MRI)-based feature tracking (FT) and to identify sources of variations. Similar analyses were also performed for strain encoding, displacement encoding with stimulated echoes, and myocardial tagging.
Background MRI-FT is a novel technique for quantification of myocardial deformation using MRI cine images. However, the reported 95% confidence intervals (CIs) from the 2 largest studies have no overlaps.
Methods Four databases (EMBASE, SCOPUS, PUBMED, and Web of Science) were systematically searched for MRI strains of the left (LV) and right (RV) ventricles. The key terms for MRI-FT were “tissue tracking,” “feature tracking,” “cardiac magnetic resonance,” “cardiac MRI,” “CMR,” and “strain.” A random effects model was used to pool LV global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS), and RVGLS. Meta-regressions were used to identify the sources of variations.
Results 659 healthy subjects were included from 18 papers for MRI-FT. Pooled mean of LVGLS was −20.1% (95% CI: −20.9% to −19.3%), LVGCS −23% (95% CI: −24.3% to −21.7%), LVGRS 34.1% (95% CI: 28.5% to 39.7%), and RVGLS −21.8% (95% CI: −23.3% to −20.2%). Although there were no publication biases except for LVGCS, significant heterogeneities were found. Meta-regression showed that variation of LVGCS was associated with field strength (β = 3.2; p = 0.041). Variations of LVGLS, LVGRS, and RVGLS were not associated with any of age, sex, software, field strength, sequence, LV ejection fraction, or LV size. LVGCS seems the most robust in MRI-FT. Among the MRI-derived strain techniques, the normal ranges were mostly concordant in LVGLS and LVGCS but varied substantially in LVGRS and RVGLS.
Conclusions The pooled means of 4 MRI-derived myocardial strain methods in normal subjects are demonstrated. Differences in field strength were attributed to variations of LVGCS.
Dr. Negishi is supported by an award from the Select Foundation, which had no role in the preparation of this paper. The authors have reported that they have no relationships relevant to the contents of this paper to disclose. Raymond Kim, MD, served as the Guest Editor for this paper.
- Received September 29, 2016.
- Revision received December 6, 2016.
- Accepted December 9, 2016.
- 2018 American College of Cardiology Foundation