title: Use of a metal ring-marked catheter for geometric calibration in quantitative coronary angiography.
abstract: Quantitative coronary angiography depends on accurate measurement of catheter shaft diameter for correction of X-ray magnification errors. We compared the use of coronary catheters with a single metal ring (R), inserted during manufacture, with measurements using the edges of the catheter shaft (S) as a calibration mark. Both ring and shaft were 2.50 mm in diameter. On unmagnified X-ray images, the ring measured 2.49 +/- 0.40 mm, and the shaft measured 2.39 +/- .040 mm in diameter. Quantitative coronary angiography using both ring and shaft for calibration provided the same percent stenosis (R:72 +/- 12; S: 71 +/- 13), but stenosis cross-sectional area was 28% different (R: 1.44 +/- .24; S: 1.84 +/- .34 mm2). Use of the catheter shaft for calibration causes overestimation of actual coronary artery dimensions. To prevent this problem, absolute measurements of coronary artery dimensions should be made with metal ring-marked catheters.
authors.affiliation: Cardiovascular Division, Mayo Clinic, Rochester, MN 55905.
authors.forename: J H
authors.initials: JH
authors.lastname: Jacobs
authors.forename: A A
authors.initials: AA
authors.lastname: Bove
authors.forename: H C
authors.initials: HC
authors.lastname: Smith
authors.forename: J H
authors.initials: JH
authors.lastname: Chesebro
mesh_terms: D000790:Angiocardiography / Q000295:instrumentation*; D002138:Calibration; D003327:Coronary Disease / Q000000981:diagnostic imaging*; D006801:Humans; D008670:Metals
chemical_list: D008670:Metals