Usefulness of 16-slice multislice spiral computed tomography for follow-up study of coronary stent implantation.

BACKGROUND Although multislice spiral computed tomography (MSCT) is a promising technique for non-invasive coronary angiography, its usefulness in patients with stent implantation remains unclear. The aim of the present study was to compare the usefulness of MSCT with that of invasive coronary angiography for evaluating coronary stent patency. METHODS AND RESULTS Thirty-one patients were enrolled after coronary stent implantation. Sixteen-slice MSCT scans were performed (39.0+/-21.8 days) before follow-up coronary angiography. After assigning an image score based on luminal visibility (1= poor, 2= fair, 3= good), factors determing image quality were analyzed. Among 42 implanted stents, 33 (78%) were assigned an image score of 3, 2 (5%) a score of 2, and 7 (17%) a score of 1. Image scores among stents with diameters >or=3.5 mm were significantly (p<0.05) higher than among smaller stents (<or=3.0 mm). Stent strut thickness did not affect image quality, but coronary calcification significantly (p<0.01) hampered the image quality. After excluding 7 stents with image scores of 1, the sensitivity, specificity, positive and negative predictive values of MSCT to identify patent stents were 83%, 90%, 63% and 96%, respectively. CONCLUSIONS MSCT can provide useful and valuable clinical information for assessing stent patency during the follow-up period when patients are treated with relatively large diameter coronary stents.