How reliable are 40 MHz IVUS and 64-slice MDCT in characterizing coronary plaque composition? An ex vivo study with histopathological comparison.
The present study investigated whether IVUS could serve as a reliable reference in validating MDCT characterization of coronary plaque against a histological gold standard. Twenty-one specimens were postmortem human coronary arteries. Coronary cross-sections were imaged by 40 MHz IVUS and by 64-slice MDCT and characterized histologically as presenting calcified, fibrous or lipid-rich plaques. Plaque composition was analyzed visually and intra-plaque MDCT attenuation was measured in Hounsfield Units (HU). 83 atherosclerotic plaques were identified. IVUS failed to characterize calcified plaque accurately, with a positive predictive value (ppv) of 75% versus 100% for MDCT. Lipid-rich plaque was even less accurately characterized, with ppv of 60 and 68% for IVUS and MDCT respectively. Mean MDCT attenuation was 966 +/- 473 HU for calcified plaque, 83 +/- 35 HU for fibrous plaque and 70.92 HU +/- 41 HU for lipid-rich plaque. No significant difference in mean MDCT attenuation was found between fibrous and lipid-rich plaques (P = 0.276). In vivo validation of MDCT against an IVUS reference thus appears to be an unsuitable and unreliable approach: 40 MHz IVUS suffers from acoustic ambiguities in plaque characterization, and 64-slice MDCT fails to analyze plaque morphology and components accurately.
Chopard
Romain
R
Department of Interventional Cardiology, Cardiovascular Hospital and Claude Bernard University, INSERM Research Unit 886 and CREATIS Research Unit associated to CNRS (UMR 5515), B.P Lyon-Monchat, 69394, Lyon Cedex 03, France.
Boussel
Loic
L
Motreff
Pascal
P
Rioufol
Gilles
G
Tabib
Alain
A
Douek
Philippe
P
Meyronet
David
D
Revel
Didier
D
Finet
Gérard
G
D000368:Aged; D002102:Cadaver; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed; D018084:Ultrasonography, Interventional