Real-time MR image acquisition during high-dose dobutamine hydrochloride stress for detecting left ventricular wall-motion abnormalities in patients with coronary arterial disease.
OBJECTIVE
To compare the accuracy of real-time magnetic resonance (MR) imaging with that of standard echo-planar MR imaging for detecting myocardial wall-motion abnormalities at rest and during dobutamine hydrochloride-induced stress in patients with coronary arterial disease.


METHODS
In 22 patients with coronary arterial disease, left ventricular wall motion was examined at rest and during dobutamine hydrochloride stress, by using echo-planar MR imaging and a new technique with real-time segmented k-space turbo gradient-echo echo-planar MR imaging (repetition time, 16.5 msec; echo time, 6.8 msec). Wall-motion abnormalities were determined visually for each perfusion territory, and Cohen kappa coefficients were calculated for real-time imaging in comparison with echo-planar imaging. Coronary angiography was performed in all patients. Sensitivity and specificity for real-time and echo-planar imaging were calculated for detecting significant coronary arterial stenosis.


RESULTS
kappa values for detecting wall-motion abnormalities at real-time imaging, in comparison with echo-planar MR imaging, were 0.97 at rest and 0.94 at maximum dobutamine hydrochloride stress. At comparison with those of angiography, the sensitivity and specificity for detecting significant coronary arterial stenosis were 88% (14 of 16 patients) and 83% (five of six patients), respectively, for echo-planar imaging and 81% (13 of 16 patients) and 83% (five of six patients), respectively, for real-time imaging.


CONCLUSIONS
Real-time MR imaging is possible under stress conditions and allows accurate detection of wall-motion abnormalities.
Department of Internal Medicine-Cardiology, German Heart Institute Berlin, Augustenburger Platz 1, Germany.
Simon
S
Schalla
Christoph
C
Klein
Ingo
I
Paetsch
Hans
H
Lehmkuhl
Axel
A
Bornstedt
Bernhard
B
Schnackenburg
Eckart
E
Fleck
Eike
E
Nagel
D002316:Cardiotonic Agents; D017023:Coronary Angiography; D003327:Coronary Disease / Q000150:complications*; D004280:Dobutamine; D017352:Echo-Planar Imaging; D005080:Exercise Test; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D012680:Sensitivity and Specificity; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis*
D002316:Cardiotonic Agents; D004280:Dobutamine