Quantification of myocardial infarct size and transmurality by contrast-enhanced magnetic resonance imaging in men.
Contrast-enhanced magnetic resonance (ce-MR) imaging allows precise delineation of infarct transmurality. An issue of debate is whether data analysis should be performed visually or quantitatively. Accordingly, a head-to-head comparison was performed between visual and quantitative analyses of infarct transmurality on ce-MR imaging. In addition, infarct transmurality was related to the severity of wall motion abnormalities at rest. In 27 patients with long-term ischemic left ventricular (LV) dysfunction (LV ejection fraction 33 +/- 8%) and previous infarction, cine MR imaging (to assess regional wall motion) and ce-MR imaging were performed. Using a 17-segment model, each segment was assigned a wall motion score (from normokinesia to dyskinesia), and segmental infarct transmurality was visually assessed on a 5-point scale (0 = no infarction, 1 = transmurality < or =25% of LV wall thickness, 2 = transmurality 26% to 50%, 3 = transmurality 51% to 75%, and 4 = transmurality 76% to 100%). Quantification of transmurality was performed with threshold analysis; myocardium showing signal intensity above the threshold was considered scar tissue, and percent transmurality was calculated automatically. Wall motion was abnormal in 56% of the 459 segments, and 55% of segments showed hyperenhancement (indicating scar tissue). The agreement between visual and quantitative analyses was excellent: 90% of segments (kappa 0.86) were categorized similarly by visual and quantitative analyses. Infarct transmurality paralleled the severity of contractile dysfunction; 96% of normal or mildly hypokinetic segments had infarct transmurality < or =25%, whereas 93% of akinetic and dyskinetic segments had transmurality >50% on visual analysis. In conclusion, visual analysis of ce-MR imaging studies may be sufficient for assessment of transmurality of infarction.
Department of Cardiology, Leiden University Medical Center, Leiden, The Netherlands.
Joanne D
JD
Schuijf
Theodorus A M
TA
Kaandorp
Hildo J
HJ
Lamb
Rob J
RJ
van der Geest
Eric P
EP
Viergever
Ernst E
EE
van der Wall
Albert
A
de Roos
Jeroen J
JJ
Bax
D000368:Aged; D003287:Contrast Media / Q000008:administration & dosage*; D006334:Heart Function Tests; D006801:Humans; D016014:Linear Models; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology; D009203:Myocardial Infarction / Q000175:diagnosis*; D009206:Myocardium / Q000473:pathology*; D011336:Probability; D011446:Prospective Studies; D011856:Radiographic Image Enhancement; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
D003287:Contrast Media