Assessing stent restenosis using 64-multidetector computed tomography coronary angiography

Seo, Myung Ki; Kho, Jin Shin; Park, So Ra; Kwang, Young Ran; Kang, Min Kyeng; Cho, Jung Hyun; An, Youn Jung; Choi, Bong Ryong; Jeong, Young Hoon; Kwak, Choong Hwan; Choi, Ho Cheol; Jeon, Kyung Nyeo; Hwang, Jin Yong

Abstract

BACKGROUND/AIMS
Multidetector computed tomography (MDCT) is considered to be a noninvasive, alternative method for evaluating stent restenosis. However, the diagnostic accuracy of 16-channel MDCT for stent stenosis is reported to have severe limitations because of high-attenuation stent-related artifacts. 64-channel MDCT, which recently became available in clinical practice, has better spatial and temporal resolution than 16-channel MDCT. The diagnostic accuracy of 64-channel MDCT for stent restenosis (in-segment and in-stent) was assessed by comparing it with conventional coronary angiography.
METHODS
In-segment and in-stent restenosis (> or =50% in diameter) were evaluated in 96 stent segments in 68 patients [61+/-12 years, 51 (75%) male] using both 64-channel MDCT and conventional coronary angiography. The in-stent analysis was confined to the portion of the artery covered by the stent and the in-segment analysis included the stent and 5 mm proximal or distal to the stent edges.
RESULTS
The 64-channel MDCT could evaluate stent restenosis in 93 of 96 (97%) stent segments. Quantitative conventional coronary angiography found in-segment restenosis (> or =50% in diameter) in 16 of 68 (23%) patients and 16 of 96 (17%) segments. For the patients with interpretable stent segments, the sensitivity, specificity, positive predictive value, and negative predictive value of 64-channel MDCT for in-segment restenosis per patient were 63, 96, 83, and 89%, respectively; per segment they were 63, 97, 83, and 93%, respectively; and for in-stent restenosis per stent they were 82, 98, 82, and 98%, respectively.
CONCLUSIONS
The diagnostic accuracy of 64-channel MDCT for assessing stent restenosis had high specificity and negative predictive value in the clinical setting. The 64-channel MDCT may be a promising, less-invasive imaging tool for stent restenosis, especially for the purpose of excluding stent restenosis.