Cardiovascular magnetic resonance myocardial feature tracking for quantitative viability assessment in ischemic cardiomyopathy

https://doi.org/10.1016/j.ijcard.2011.10.137Get rights and content

Abstract

Background

Low dose dobutamine stress magnetic resonance imaging is valuable to assess viability in patients with ischemic cardiomyopathy. Analysis is usually qualitative with considerable operator dependency. The aim of the current study was to investigate the feasibility of cine images derived quantitative cardiac magnetic resonance (CMR) myocardial feature tracking (FT) strain parameters to assess viability in patients with ischemic cardiomyopathy.

Methods

15 consecutive patients with ischemic cardiomyopathy referred for viability assessment were studied at 3 T at rest and during low dose dobutamine stress (5 and 10 μg/kg/min of dobutamine). Subendocardial and subepicardial circumferential (Eccendo and Eccepi) and radial (Err) strains were assessed using steady state free precession (SSFP) cine images orientated in 3 short axis slices covering 16 myocardial segments.

Results

Dysfunctional segments without scar (n = 75) improved in all three strain parameters: Eccendo (Rest: − 10.5 ± 6.9; 5 μg: − 12.1 ± 6.9; 10 μg: − 14.1 ± 9.2; p < 0.05), Eccepi (Rest: − 7 ± 4.8; 5 μg: − 8.2 ± 5.5; 10 μg: − 9.1 ± 5.9; p < 0.05) and Err (Rest: 11.7 ± 8.3; 5 μg: 16 ± 10.9; 10 μg: 16.5 ± 12.8; p < 0.05).

There was no response to dobutamine in dysfunctional segments with scar transmurality above 75% (n = 6): Eccendo (Rest: − 4.7 ± 3.0; 5 μg: − 2.9 ± 2.5; 10 μg: − 6.6 ± 3.3; p = ns), Eccepi (Rest: − 2.9 ± 2.9; 5 μg: − 5.4 ± 3.9; 10 μg: − 4.5 ± 4.2; p = ns) and Err (Rest:9.5 ± 5; 5 μg:5.4 ± 6.2; 10 μg:4.9 ± 3.3; p = ns). Circumferential strain (Eccendo, Eccepi) improved in all segments up to a transmurality of 75% (n = 60; p < 0.05). Err improved in segments < 50% transmurality (n = 45; p < 0.05) and remained unchanged above 50% transmurality (n = 21; p = ns).

Conclusions

CMR-FT is a novel technique, which detects quantitative wall motion derived from SSFP cine imaging at rest and with low dose dobutamine stress. CMR-FT holds promise of quantitative assessment of viability in patients with ischemic cardiomyopathy.

Introduction

Cardiovascular magnetic resonance (CMR) plays an increasingly important role in the diagnosis and assessment of coronary artery disease (CAD) as it has evolved into a comprehensive clinical tool with the unique capability of assessing myocardial function, viability and perfusion in one examination [1], [2]. Wall motion analysis is a central component of clinical routine. Due to its excellent image quality CMR is the gold standard for visualizing left ventricular (LV) endocardial wall motion at rest and also during low and high dose dobutamine challenges for the assessment of myocardial viability and ischemia [3], [4]. At present image analysis is mainly performed qualitatively with considerable operator dependency [5]. Quantitative analysis with myocardial tagging requires the acquisition of additional sequences and involves lengthy post processing [6]. Recently myocardial feature tracking (FT) has been introduced, which is an analog to echocardiographic speckle tracking [7]. This technique tracks tissue voxel motion in cine magnetic resonance (MR) images, which allows assessment of circumferential and radial myocardial strain. Therefore the acquisition of additional sequences is not required. Good agreement has been demonstrated between CMR-FT and harmonic phase imaging (HARP), a tagging based reference standard [8]. It has also been validated in normal volunteers during intermediate dose dobutamine stress [9].

The aim of the current study was therefore to determine the feasibility of CMR-FT for the quantitative detection of viable myocardium during low-dose dobutamine stress in a patient population with ischemic cardiomyopathy.

Section snippets

Methods

Consecutive patients (n = 15) referred for evaluation of ischemic cardiomyopathy were enrolled in this study and underwent CMR imaging on a 3 T clinical MR scanner (Achieva, Philips Medical Systems, Best, The Netherlands). The local ethics committee approved the study protocol. All patients gave written informed consent before the CMR examination.

Results

Dobutamine was tolerated in all 15 patients. The image quality was sufficient to perform strain analysis in 87% of all segments (208 of 240, Fig. 1). 32 segments were excluded due to insufficient quality due to breathing artifacts (n = 26) or inclusion of the outflow tract in the basal slice (n = 6) either at rest or any stress level. Participant demographics are shown in Table 1.

Discussion

The current study includes a population of patients with ischemic cardiomyopathy studied at rest and with low-dose dobutamine stress and demonstrates several important findings.

Firstly, CMR-FT can quantify changes in wall mechanics between rest and dobutamine stress in patients with ischemic cardiomyopathy. Secondly, there is an increase in strain in viable segments without LGE whereas there is no change in segments with transmural late gadolinium enhancement. Finally, there is considerable

Conclusions

CMR-FT allows derivation of strain mechanics from SSFP cine images at rest and during low dose dobutamine stress in patients with ischemic cardiomyopathy. Results correlate closely with the transmurality of myocardial scarring and visual analysis. If the current analysis algorithm can be further improved to reduce inter- and intra-observer variability CMR-FT could potentially result in simple and fast quantification of myocardial strain and may therefore aid assessment of contractile reserve

Competing interests

Eike Nagel received minor consultancy fees from Philips Healthcare and major grant support from Philips Healthcare and Bayer Schering Pharma. The other authors declare that they have no competing interests.

Acknowledgments

Andreas Schuster is a British Heart Foundation (BHF) Clinical Research Fellow (FS/10/029/28253). The authors of this manuscript have certified that they comply with the Principles of Ethical Publishing in the International Journal of Cardiology.

References (32)

Cited by (91)

  • “Health-Related Quality of Life in Operated Adult Patients with Tetralogy of Fallot and Correlation with Advanced Imaging Indexes and Cardiopulmonary Exercise Test” A Narrative Review

    2023, Current Problems in Cardiology
    Citation Excerpt :

    Myocardial strain allows quantitative measurement of global but also regional myocardial function and deformation, offering additional information beyond ejection fraction. It enables early detection of subclinical myocardial dysfunction in patients with ischemic and non-ischemic heart disease and in preserved ejection fraction without wall motion abnormalities.53-59 In 58 rToF patients, Lu et al. analyzed Global Longitudinal and Circumferencial strain of both the RV and LV as well as RV segments individually.

  • Regional myocardial strain by cardiac magnetic resonance feature tracking for detection of scar in ischemic heart disease

    2020, Magnetic Resonance Imaging
    Citation Excerpt :

    FT-CMR, on the other hand, can be applied to cine CMR images that are routinely acquired as an essential component of every CMR examination without the need for additional images. To our knowledge, there are almost no previous studies that focused on FT-derived regional strain and its relationship with scar in patients with chronic CAD [24]. The ability to robustly assess regional myocardial strain is of significant clinical importance.

View all citing articles on Scopus

Grant support: Andreas Schuster and Eike Nagel were supported by the British Heart Foundation (BHF) (, ) and the Biomedical Research Centre (BRC-CTF 196). Eike Nagel received significant grant support from Bayer Schering Pharma and Philips Healthcare.

View full text