Strain-encoded cardiac MR during high-dose dobutamine stress testing: comparison to cine imaging and to myocardial tagging.
OBJECTIVE
To investigate regional strain response during high-dose dobutamine stress cardiac magnetic resonance imaging (DS-CMR) using myocardial tagging and Strain-Encoded MR (SENC).


METHODS
Stress induced ischemia was assessed by wall motion analysis, by tagged CMR and by SENC in 65 patients with suspected or known CAD who underwent DS-CMR in a clinical 1.5 Tesla scanner. Coronary angiography deemed as the standard reference for the presence or absence of CAD (> or =50% diameter stenosis) in all patients.


RESULTS
SENC and conventional tagging detected abnormal strain response in six and five additional patients, respectively, who were missed by cine images and proved to have CAD by angiography (P < 0.05 for SENC versus cine, P = 0.06 for tagging versus cine and p = NS for SENC versus tagging). On a per-vessel level, wall motion analysis on cine images showed high specificity (95%) but moderate sensitivity (70%) for the detection of CAD. Tagging and SENC yielded significantly higher sensitivity of 81% and 89%, respectively (P < 0.05 for tagging and P < 0.01 for SENC versus wall motion analysis, and p = NS for SENC versus tagging), while specificity was equally high (96% and 94%, respectively, P = NS for all).


CONCLUSIONS
Both the direct color-coded visualization of strain on CMR images and the generation of additional visual markers within the myocardium with tagged CMR represent useful adjuncts for DS-CMR, which may provide incremental value for the detection of CAD in humans. J. Magn. Reson.
Korosoglou
Grigorios
G
University of Heidelberg, Department of Cardiology, Heidelberg, Germany. bkorosoglou@hotmail.com
Futterer
Simon
S
Humpert
Per M
PM
Riedle
Nina
N
Lossnitzer
Dirk
D
Hoerig
Birgit
B
Steen
Henning
H
Giannitsis
Evangelos
E
Osman
Nael F
NF
Katus
Hugo A
HA
D000465:Algorithms; D003324:Coronary Artery Disease / Q000175:diagnosis*; D004280:Dobutamine; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005080:Exercise Test; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013194:Staining and Labeling; D014665:Vasodilator Agents
D014665:Vasodilator Agents; D004280:Dobutamine