title: Minimally invasive evaluation of coronary stents with electron beam computed tomography: In vivo and in vitro experience.
abstract: We sought to describe the value of electron beam computed tomography (EBCT) to detect stent restenoses at follow-up and to identify characteristic EBCT features of coronary stents. Six coronary stents (GRII, Jostent, NIR, PS, Micro, Wiktor) were scanned in vitro (10 1. 5-mm-thick slices, 15-cm FoV, 100-ms AT) before and after inflation with 3.0-, 3.5-, and 4.0-mm balloons to study intensity values and different stent dimensions in comparison to caliper measurements. In 44 patients (60 +/- 10 years, 4 females) we prospectively compared EBCT findings [eight 8-mm-thick slices in the flow mode, 26-cm field of view (FoV), 50 ms acquisition time (AT)] with 6-month angiographic outcome after placement of 86 stents in 49 vessels. For the detection of significant angiographic luminal narrowing (>/=75%) that occurred in 17/49 vessels (35%), we found a sensitivity of 65%, a specificity of 84%, and a positive and negative predictive value of 69% and 82%, respectively. The in vitro data show significant differences in image intensity between the stents and a significant gradual decrease in image intensity with increasing stent diameters. The mean differences between EBCT and caliper measurements for the length and diameter were 0.17 +/- 0.18 mm and -0.32 +/- 0.25mm, respectively. EBCT is currently the only noninvasive technique that allows the assessment of stent dimensions and stent geometry, which may prove useful in patients when intravascular ultrasound cannot be performed. Contrast-enhanced EBCT is a promising tool for minimally invasive stent patency evaluation at follow-up, especially in patients that are unable to exercise. Cathet. Cardiovasc. Intervent. 48:39-47, 1999.
authors.affiliation: Department of Physiology and Biophysics and Department of Cardiovascular Diseases, Mayo Clinic, Rochester, Minneapolis 55905, USA. moehlenkamp.stefan@mayo.edu
authors.forename: S
authors.initials: S
authors.lastname: Möhlenkamp
authors.forename: H
authors.initials: H
authors.lastname: Pump
authors.forename: D
authors.initials: D
authors.lastname: Baumgart
authors.forename: M
authors.initials: M
authors.lastname: Haude
authors.forename: D H
authors.initials: DH
authors.lastname: Grönemeyer
authors.forename: R M
authors.initials: RM
authors.lastname: Seibel
authors.forename: R S
authors.initials: RS
authors.lastname: Schwartz
authors.forename: R
authors.initials: R
authors.lastname: Erbel
mesh_terms: D017023:Coronary Angiography; D003327:Coronary Disease / Q000000981:diagnostic imaging / Q000628:therapy; D003331:Coronary Vessels; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012008:Recurrence; D012680:Sensitivity and Specificity; D015607:Stents; D014057:Tomography, X-Ray Computed