Coronary stent assessability by 64 slice multi‐detector computed tomography

Background : We evaluated the assessability of contemporary stent platforms by 64‐slice multi‐detector computed tomography (MDCT). Methods . Patients undergoing coronary stenting were included in a prospective protocol of MDCT imaging within 48 hr of stent implantation. MDCT data were acquired using a “Sensation 64” MDCT scanner (Siemens Medical Solutions, Forchheim, Germany). Stent assessability was assessed by two independent blinded observers and disagreement was resolved by a third observer. Assessability was defined at visualization of the in‐stent lumen without influence of partial volume effects, beam hardening, motion, calcification, or contrast to noise limitations. Results : Fifty four stents (Cypher n = 25, Vision/Minivision n = 19, Taxus Express n = 8, Liberte n = 1, Driver n = 1) in 44 patients were included in the study. The two independent observers classified 30 of 54 stents (56%) as assessable. Interobserver reproducibility was good with κ = 0.66. Stent size was the most important determinant of assessability. Consistently assessable stents were 3.0 mm or larger (85%), whereas those under 3 mm were mostly nonassessable (26%). Conclusions : Contemporary stent designs evaluated on a 64‐slice MDCT scanner showed artifact free assessability only in larger stents. Increase in spatial resolution of MDCT scanners or modifications in stent design will be necessary to noninvasive evaluate stents <3 mm in diameter, where in‐stent restenosis is more frequent. © 2007 Wiley‐Liss, Inc.