title: [Six-month intravascular ultrasound follow-up of coronary bifurcation lesions treated with rapamycin-eluting stents: technical considerations].
abstract: OBJECTIVE
  In vitro studies show that stents deform when dilated laterally to access a side branch. This phenomenon may be avoided by use of a kissing balloon at the end of the procedure. However, to date, no in vivo data are available. Our objectives were to investigate the main vessel stent using intravascular ultrasound (IVUS) at six-month follow-up in 55 patients with bifurcation lesions treated using rapamycin-eluting stents and to examine the effect of technical factors.
  
  
  METHODS
  All patients were treated using provisional or T stents. At 6 months, IVUS measurements were made in the main vessel at both proximal and distal ends of the stent, in reference segments, immediately below the side branch ostium, and at the points where the lumen was smallest and where stent expansion was greatest.
  
  
  RESULTS
  The lumen area immediately below the side branch ostium was significantly smaller than that at the point of maximum stent expansion (6.7 [1.8] vs 5.1 [1.3] mm2; P<.05). Underexpansion was not influenced by use of a kissing balloon (stent area immediately under the side branch ostium: 5.5 [0.9] vs 5.6 [1.6] mm2; P=NS) and only one patient experienced restenosis at this point. The lumen areas at the proximal and distal edges of the stent were almost identical in patients who did or did not undergo balloon dilation beyond the ends of the stent.
  
  
  CONCLUSIONS
  Stent underexpansion below the side branch ostium was frequently found following provisional or T stenting of bifurcation lesions. This minor stent deformity was not prevented by use of a kissing balloon nor by any specific side branch treatment and had no significant impact on the restenosis rate.
authors.affiliation: Servicio de Cardiología, Hospital Reina Sofía, Universidad de Córdoba, Córdoba, España. grupo_corpal@arrakis.es
authors.forename: Manuel
authors.initials: M
authors.lastname: Pan
authors.forename: José
authors.initials: J
authors.lastname: Suárez de Lezo
authors.forename: Alfonso
authors.initials: A
authors.lastname: Medina
authors.forename: Miguel
authors.initials: M
authors.lastname: Romero
authors.forename: Antonio
authors.initials: A
authors.lastname: Delgado
authors.forename: José
authors.initials: J
authors.lastname: Segura
authors.forename: Soledad
authors.initials: S
authors.lastname: Ojeda
authors.forename: Djordje
authors.initials: D
authors.lastname: Pavlovic
authors.forename: Javier
authors.initials: J
authors.lastname: Ariza
authors.forename: Jaime
authors.initials: J
authors.lastname: Fernández-Dueñas
authors.forename: Juan
authors.initials: J
authors.lastname: Herrador
authors.forename: Isabel
authors.initials: I
authors.lastname: Ureña
mesh_terms: D003131:Combined Modality Therapy; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000628:therapy*; D016503:Drug Delivery Systems; D004867:Equipment Design; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D020123:Sirolimus / Q000008:administration & dosage*; D015607:Stents; D013997:Time Factors; D018084:Ultrasonography, Interventional
chemical_list: D007166:Immunosuppressive Agents; D020123:Sirolimus