Value of additional strain analysis with feature tracking in dobutamine stress cardiovascular magnetic resonance for detecting coronary artery disease

Abstract

BackgroundDobutamine stress cardiovascular magnetic resonance (DS-CMR) has been established for the detection of coronary artery disease (CAD). The novel technique feature tracking (FT) analyses left ventricular circumferential strain (Ecc) thus offering detailed information about myocardial deformation. The purpose of this study was to evaluate FT based Ecc for the detection of myocardial ischemia during DS-CMR.MethodsA total of 25 patients (18 males; mean age 64 ± 10 years) with suspected or known CAD underwent a standardized high-dose DS-CMR protocol at 1.5 T. For FT analysis cine short axis (SAX) views (apical, medial, basal) at rest and during maximum dobutamine stress were used. None of the patients had wall motion abnormalities (WMAs) or impaired left ventricular function at rest or scar tissue. For analysis of Ecc the three SAX planes were divided into 16 segments (n = 400 segments). During stress 15 patients (34 segments) developed WMAs as assessed by visual analysis. All patients underwent x-ray coronary angiography for clinical reasons which served as the reference standard. Patients without WMAs during DS-CMR and exclusion of stenotic CAD were defined as normal (10 patients, 160 segments). In patients with significant CAD segments that were supplied by a vessel of >70% narrowing were defined as stenotic (n = 64). The remaining segments in patients with significant CAD were considered as remote (n = 176).ResultsAt rest no differences in Ecc were observed between normal, stenotic and remote segments. High-dose dobutamine stress revealed highly significant differences between Ecc of normal and stenotic segments (p < 0.001), as well as between remote and stenotic segments (p < 0.001). The same observation took place for the absolute change of Ecc (p < 0.001 and p = 0.01). ROC analysis of Ecc during maximum DS-CMR differentiated normal from stenotic segments with a sensitivity of 75% and specificity of 67% using a cutoff -33.2% with an area under the curve of 0.78. Additional analysis of intermediate-dose dobutamine also showed a significant difference between normal and stenotic segments (p = 0.001).ConclusionFT based analysis of Ecc during intermediate- and high-dose DS-CMR was feasible and differentiated between stenotic, remote and normal segments. Quantitative assessment of Ecc with FT may improve the diagnostic accuracy of DS-CMR for detection of ischemia.

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

“…Reproducibility and sample sizes may therefore be different in patients or when image quality is reduced. However, although dobutamine stimulation may reduce image quality, a previous MR-FT study in a patient group with coronary artery disease even demonstrated improved MR-FT reproducibility during dobutamine exposure as compared to measurements at rest (23). …”

Cardiovascular Magnetic Resonance Myocardial Feature Tracking

“…This is in line with previous evidence from myocardial tagging suggesting that quantification of wall motion with strain enhances diagnostic accuracy when compared with visual analysis for the detection of ischemia during high-dose dobutamine stress. 32 On the basis of CMR-FT, Schneeweis et al 23 have reproduced an important finding that quantitative impairments of myocardial strain defined by strain encoding imaging already occur at intermediate dobutamine levels. 33 Because CMR-FT does not require the acquisition of extra sequences (when compared with strain encoding imaging) and the risk of adverse events when diagnosing coronary disease at intermediate dobutamine levels is low, there could be clinical benefit of using CMR-FT during ischemia testing.…”

“…30,31 Assessment of ventricular deformation at rest and with inotropic stimulation using dobutamine has provided clinically relevant data in health 18,20 and disease states. 23, 24 Schneeweis et al 23 demonstrated the ability to use circumferential short-axis strain to identify inducible ischemia during intermediate and high-dose dobutamine stimulation. This is in line with previous evidence from myocardial tagging suggesting that quantification of wall motion with strain enhances diagnostic accuracy when compared with visual analysis for the detection of ischemia during high-dose dobutamine stress.…”

“…CMR-FT has been applied for ischemia 23 and viability 24 detection, cardiomyopathies, 25,26 pulmonary hypertension, 27 and quantification of dyssynchrony. 28,29 Reference values for LV circumferential, radial and longitudinal strain have been published recently.…”

Review of Journal of Cardiovascular Magnetic Resonance 2015

“…Recent advances reported in the journal have included improved flow mapping, [1–3] real-time imaging, [4] T1 mapping, [5–7] simulations, [8, 9] perfusion, [10–12] coronary imaging, [13] diffusion tensor imaging, [14–16] feature tracking, [17–20] and strain assessment. [21, 22] The full breadth of new developments is described in the papers in the section.…”