title: Clinical utility of low-pressure implantation of drug-eluting stent into very small vessels.
abstract: BACKGROUND
  Although drug-eluting stents (DES) reduce restenosis, the best strategy for DES implantation in small vessels has not been established.
  
  
  OBJECTIVE
  We investigated the clinical usefulness of low-pressure implantation of a 2.5-mm DES for small vessels less than 2.5mm in diameter.
  
  
  METHODS
  In 118 patients, a 2.5-mm DES was implanted for small vessels less than 2.5mm in diameter between 2007 and 2009 in our hospital. The patients were divided into two groups by initial deployment pressure: low-pressure (LP; n=46) and nominal-pressure (NP; n=72).
  
  
  RESULTS
  Patients with impaired glucose tolerance were more frequent (p=0.02) and the target vessel diameter was significantly smaller (p=0.01) in the LP group than in the NP group. A smaller minimum lumen diameter (MLD) was obtained (LP: 2.22±0.27mm vs. NP: 2.34±0.26mm, p=0.02) after DES implantation with a smaller balloon-to-artery ratio (p=0.03) in the LP group. However, at mid-term follow-up (7.7±3.9 months), MLD (p=0.55) and the binary restenosis rate (LP: 2.6% vs. NP: 11.1%, p=0.12) were not significantly different between the LP and NP groups. Furthermore, by Kaplan-Meier analysis, the incidence of major adverse cardiac events was not different between the groups during the long-term follow-up (32.4±8.6 months).
  
  
  CONCLUSIONS
  The present study indicates that low-pressure implantation of 2.5-mm DES for very small vessels may be feasible with regard to short- and long-term clinical outcomes.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Kinki University Faculty of Medicine, Osakasayama, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Suga
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Kinki University Faculty of Medicine, Osakasayama, Japan.
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Iwanaga
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Kinki University Faculty of Medicine, Osakasayama, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kobuke
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Kinki University Faculty of Medicine, Osakasayama, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Morimoto
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Kinki University Faculty of Medicine, Osakasayama, Japan.
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Ikuta
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Kinki University Faculty of Medicine, Osakasayama, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Ueno
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Kinki University Faculty of Medicine, Osakasayama, Japan.
authors.forename: Naoya
authors.initials: N
authors.lastname: Kobayashi
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Kinki University Faculty of Medicine, Osakasayama, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Yamaji
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Kinki University Faculty of Medicine, Osakasayama, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Ikeda
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Kinki University Faculty of Medicine, Osakasayama, Japan. Electronic address: smiyazak@med.kindai.ac.jp.
authors.forename: Shunichi
authors.initials: S
authors.lastname: Miyazaki
mesh_terms: D000368:Aged; D017023:Coronary Angiography; D003327:Coronary Disease / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D023903:Coronary Restenosis / Q000517:prevention & control; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000473:pathology; D054855:Drug-Eluting Stents; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D062645:Percutaneous Coronary Intervention / Q000379:methods*; D013997:Time Factors; D016896:Treatment Outcome
keywords: Clinical outcome; Coronary artery disease; Drug-eluting stent; Small vessel disease