Identification and viability assessment of infarcted myocardium with late enhancement multidetector computed tomography: comparison with thallium single photon emission computed tomography and echocardiography.
BACKGROUND
Recent studies revealed that multidetector computed tomography late enhancement (MDCT-LE) is a reliable technique for detecting necrotic and scarred myocardial tissue. The aims of the study were to identify infarcted myocardium using MDCT-LE protocol in patients after myocardial infarction (MI) and assess viability in resting wall motion abnormalities.


METHODS
One hundred one patients with previous MI (62 +/- 13 years, 1-6 months after MI) underwent MDCT-LE (15 minutes after contrast medium administration), rest-redistribution thallium single photon emission computed tomography (Tl-SPECT), and dobutamine echocardiography (DbE). In a 17-segment model, infarcted myocardium detected by MDCT-LE was categorized as none, 1%-25%, 26%-50%, 51%-75%, or >75% segmental extent and was compared with decreased uptake of Tl-SPECT and contractile function by DbE on per patient and segmental basis in a blinded fashion.


RESULTS
By per patient analysis, MDCT-LE identified the presence of infarcted myocardium in 97 patients (96%), and Tl-SPECT decreased uptake in 88 patients (87%), (P = .02). By per segment analysis, the concordance for detecting infarcted myocardium was good (kappa value = 0.792). In segments with resting wall motion abnormalities (N = 486), there was moderate concordance in assessing viability (kappa value between MDCT and Tl-SPECT = 0.555, MDCT and DbE = 0.498, Tl-SPECT and DbE = 0.478) with predefined MDCT-LE threshold of 50% segmental extent. Among segments with MDCT-LE >75% segmental extent, the proportion designated nonviable by Tl-SPECT and DbE reached 87.8% and 92.2%, respectively.


CONCLUSIONS
Multidetector computed tomography late enhancement is accurate in identifying the presence and extent of infarcted myocardium. Its segmental extent has good correlation with the magnitude of thallium decreased uptake and can predict contractile reserve. Multidetector computed tomography late enhancement can be an alternative to assess viability.
Chiou
Kuan-Rau
KR
Department of Internal Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan, Republic of China.
Liu
Chun-Peng
CP
Peng
Nan-Jing
NJ
Huang
Wei-Chun
WC
Hsiao
Shih-Hung
SH
Huang
Yi-Luan
YL
Chen
Kuen-Huang
KH
Wu
Ming-Ting
MT
D000368:Aged; D025401:Echocardiography, Stress; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000503:physiopathology; D009206:Myocardium / Q000378:metabolism / Q000473:pathology; D012680:Sensitivity and Specificity; D013794:Thallium Radioisotopes / Q000378:metabolism; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed
D013794:Thallium Radioisotopes