title: Non-ischemic perfusion defects due to delayed arrival of contrast material on stress perfusion cardiac magnetic resonance imaging after coronary artery bypass graft surgery.
abstract: Herein we report about the adenosine stress perfusion MR imaging findings of a 50-year-old man who exhibited two different perfusion defects resulting from two different mechanisms after a coronary artery bypass surgery. An invasive coronary angiography confirmed that one perfusion defect at the mid-anterior wall resulted from an ischemia due to graft stenosis. However, no stenosis was detected on the graft responsible for the mid-inferior wall showing the other perfusion defect. It was assumed that the perfusion defect at the mid-inferior wall resulted from delayed perfusion owing to the long pathway of the bypass graft. The semiquantitative analysis of corrected signal-time curves supported our speculation, demonstrating that the rest-to-stress ratio index of the maximal slope of the myocardial territory in question was similar to those of normal myocardium, whereas that of myocardium with the stenotic graft showed a typical ischemic pattern. A delayed perfusion during long graft pathway in a post-bypass graft patient can mimick a true perfusion defect on myocardial stress MR imaging. Radiologists should be aware of this knowledge to avoid misinterpretation of graft and myocardial status in post bypass surgery patients.
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul 110-744, Korea.
authors.forename: Yeo Koon
authors.initials: YK
authors.lastname: Kim
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul 110-744, Korea.
authors.forename: Eun-Ah
authors.initials: EA
authors.lastname: Park
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul 110-744, Korea.
authors.forename: Sang Joon
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Department of Neuclear Medicine, Seoul National University Hospital, Seoul 110-744, Korea.
authors.forename: Gi Jeong
authors.initials: GJ
authors.lastname: Cheon
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul 110-744, Korea.
authors.forename: Whal
authors.initials: W
authors.lastname: Lee
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul 110-744, Korea.
authors.forename: Jin Wook
authors.initials: JW
authors.lastname: Chung
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul 110-744, Korea.
authors.forename: Jae Hyung
authors.initials: JH
authors.lastname: Park
mesh_terms: D000241:Adenosine; D003287:Contrast Media / Q000493:pharmacokinetics*; D017023:Coronary Angiography / Q000379:methods*; D001026:Coronary Artery Bypass / Q000379:methods*; D023921:Coronary Stenosis / Q000175:diagnosis*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods
chemical_list: D003287:Contrast Media; D000241:Adenosine
keywords: Cardiac magnetic resonance imaging; Coronary artery bypass graft; Semiquantitative analysis; Stress perfusion test