Non-invasive magnetic resonance imaging of coronary bypass grafts. comparison of the haste- and navigator techniques with conventional coronary angiography.
OBJECTIVE
The aim was the study was to evaluate the patency of coronary artery bypass grafts with the 3D Navigator and the Haste magnetic resonance imaging techniques.


METHODS
Thirty-four patients with 82 grafts (18 internal mammarian artery and 64 saphenous venous grafts) were examined at 1.5 T using a phased arrray body coil. A 2D T-2 weighted turbo spin echo sequence (Haste) and a 3D-angiography sequence in navigator technique were used. Reference method was the conventional coronary angiography that was performed within 7 days.


RESULTS
With the HASTE sequence 54 of 56 patent and 12 of the 16 occluded grafts were recognized, the sensitivity and specificity was 96 and 75%. The distal anastomosis could be assessed in 28 of 76 cases. With the Haste sequence 54 of the 56 patent and 12 of the 14 occluded grafts were detected correctly. Eight patent and two occluded grafts were judged as not assessable. The sensitivity and specificity was 96 and 85%. Sixty-six percent (50/76) of the distal anastomosis were identified correctly. With both sequences none of the bypass stenosis could be detected.


CONCLUSIONS
The patency of coronary bypass grafts can be evaluated noninvasively with a sensitivity of 96% and a specificity of 76%. No inference can be made with respect to the nature of bypass graft stenosis. Better results can be expected with the development of a blood pool contrast medium, an improvement of the spatial resolution and in the combination of flow measurements.
Wittlinger
Th
T
Department of Radiology, 2nd Medical Clinic, University Hospital, Langenbeckstrasse 1, 55101 Mainz, Germany. thomaswittlinger@t-online.de
Voigtländer
T
T
Kreitner
K F
KF
Kalden
P
P
Thelen
M
M
Meyer
J
J
D000368:Aged; D000714:Anastomosis, Surgical; D003287:Contrast Media; D017023:Coronary Angiography; D001026:Coronary Artery Bypass; D005260:Female; D006083:Graft Occlusion, Vascular / Q000175:diagnosis*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D014654:Vascular Patency
D003287:Contrast Media