title: Impact of moderate lesion calcium on mechanisms of coronary stenting as assessed with three-dimensional intravascular ultrasound in vivo.
abstract: Axial plaque redistribution is an important mechanism of lumen enlargement after stenting of noncalcified lesions. To assess effects of lesion calcification on mechanisms of coronary stenting, we analyzed 55 lesions with noncircumferential calcification with 3-dimensional intravascular ultrasound (IVUS) (standard qualitative and quantitative analyses) before and after implantation of balloon-expandable stents. Thirty-two plaques (58%) showed arcs of calcium <120 degrees of vessel circumference (group A), whereas 23 lesions (42%) contained arcs of calcium > or =120 degrees of vessel circumference (group B). In the entire cohort of 55 lesions, as well as groups A and B, which were studied separately, both single-slice IVUS analysis (performed at minimum lumen site before intervention) and mean stented segment IVUS analysis showed an increase in lumen and vessel area and a decrease in plaque area (p <0.001). The magnitude of lumen and vessel increase and of plaque decrease was similar in both groups. Group A lesions showed significant plaque extrusion into the distal reference segment that was not observed in group B (increase in plaque area of 1.3 +/- 1.9 vs 0.1 +/- 2.0 mm(2), p <0.04). Stenting did not alter plaque area of the proximal reference segment in either group. In addition, there was an increase in vessel area of the distal reference of both groups, indicating that stent-induced vessel expansion observed within the lesion also affected the distal reference. Thus, longitudinal plaque redistribution and vessel expansion contribute to increased lumen dimensions during stenting of lesions with varying amounts of calcium; however, marked plaque extrusion was found only in lesions with a calcium arc of <120 degrees.
authors.affiliation: Department of Cardiology, Essen University, Essen, Germany. von.birgelen@freeler.nl
authors.forename: Clemens
authors.initials: C
authors.lastname: von Birgelen
authors.forename: Gary S
authors.initials: GS
authors.lastname: Mintz
authors.forename: Dirk
authors.initials: D
authors.lastname: Böse
authors.forename: Dietrich
authors.initials: D
authors.lastname: Baumgart
authors.forename: Michael
authors.initials: M
authors.lastname: Haude
authors.forename: Heinrich
authors.initials: H
authors.lastname: Wieneke
authors.forename: Till
authors.initials: T
authors.lastname: Neumann
authors.forename: Jens
authors.initials: J
authors.lastname: Brinkhoff
authors.forename: Matthias
authors.initials: M
authors.lastname: Jasper
authors.forename: Raimund
authors.initials: R
authors.lastname: Erbel
mesh_terms: D000368:Aged; D002114:Calcinosis / Q000000981:diagnostic imaging*; D017023:Coronary Angiography; D023921:Coronary Stenosis / Q000628:therapy*; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015607:Stents; D018084:Ultrasonography, Interventional