This analysis compared the results of electron beam computed tomography (EBCT) with
those of coronary angiography and intracoronary ultrasound (ICUS) for the in vivo
detection of coronary atherosclerotic plaques.
EBCT is a new imaging modality for identification of coronary calcifications. Coronary
angiography depicts advanced changes in coronary morphology, whereas ICUS is an established
diagnostic tool that detects the early stages of coronary artery disease.
In 57 patients (54 +/- 9 years old), 267 coronary segments were analyzed with EBCT
(3-mm slices, acquisition time 100 ms, threshold definition of coronary calcification
at 130 Hounsfield units in an area > or = 1 mm2, Agatston calcium score), coronary
angiography and ICUS. The analysis was based on the number and extent of coronary
calcifications on EBCT, coronary lumen reduction on coronary angiography and plaque
formation with and without ultrasound signs of calcifications on ICUS.
Compared with coronary angiography, EBCT yielded a sensitivity of 66%, a specificity
of 78%, a positive predictive value of 39% and a negative predictive value of 91%.
Compared with ICUS, EBCT yielded an overall sensitivity of 66%, a specificity of 88%
and an overall accuracy of 81%. For plaques with and without ultrasound signs of calcifications,
the sensitivity of EBCT was 97% and 47%, specificity 80% and 75% and overall accuracy
82% and 69%, respectively.
This in vivo correlation between ICUS and EBCT demonstrates that EBCT is a noninvasive
method that helps to visualize the atherosclerotic process by localization and quantification
of coronary artery calcifications. EBCT detects calcified plaques with high accuracy.
Plaques without ultrasound signs of calcifications can be detected by EBCT but with
lower sensitivity but equivalent specificity.