title: Intracoronary brachytherapy with beta-radiation for the treatment of long diffuse in-stent restenosis.
abstract: OBJECTIVE
  To assess the efficacy of intracoronary brachytherapy with beta-radiation (Sr/Y) for the treatment of long diffuse in-stent restenosis (ISR).
  
  
  METHODS
  As recurrent ISR depends on intimal injury after coronary angioplasty, long in-stent restenotic lesions were defined as lesions with a treatment length >26 mm (lesion length >20 mm plus a treatment margin of 3 mm at each end). Seventy-eight patients with long ISR were treated at our institution with beta-brachytherapy after coronary angioplasty. Patients were irradiated with either an approximate dose of 12 Gy at 1 mm vessel wall depth or with 18 Gy at 1 mm vessel wall depth. Clinical follow-up was available for 69 patients and angiographic follow-up for 65 patients. Late lumen loss (LLL), binary restenosis (stenosis >50%), target lesion revascularization (TLR) and major adverse cardiac events (MACE) were assessed for a follow-up time of 6.6+/-2.2 months.
  
  
  RESULTS
  Mean interventional treatment length was 46+/-18 mm. TLR was performed in all 23 patients with binary restenosis (33%). Death of cardiac cause was reported for two patients, one of whom did not undergo TLR. Thus, overall MACE rate was 35%. Recurrent ISR was significantly more frequent in patients with geographic miss. Comparison of the different radiation dose regimens revealed significantly lower LLL in patients irradiated with the higher dose (0.20+/-0.68 mm compared with 0.65+/-0.96 mm, P=0.03).
  
  
  CONCLUSIONS
  Intracoronary brachytherapy with beta-radiation (Sr/Y) is a safe and effective therapeutic option for the reduction of recurrent ISR in long diffuse lesions. We recommend a high-dose irradiation with 18 Gy at 1 mm vessel wall depth.
authors.affiliation: Department of Internal Medicine II, Medical School of Vienna, Austria. christophschukro@hotmail.com
authors.forename: Christoph
authors.initials: C
authors.lastname: Schukro
authors.forename: Bonni
authors.initials: B
authors.lastname: Syeda
authors.forename: Rainer
authors.initials: R
authors.lastname: Schmid
authors.forename: Andreas
authors.initials: A
authors.lastname: Stemberger
authors.forename: Irene
authors.initials: I
authors.lastname: Lang
authors.forename: Michael
authors.initials: M
authors.lastname: Derntl
authors.forename: Thomas
authors.initials: T
authors.lastname: Neunteufl
authors.forename: Günter
authors.initials: G
authors.lastname: Christ
authors.forename: Christian
authors.initials: C
authors.lastname: Kirisits
authors.forename: Boris
authors.initials: B
authors.lastname: Pokrajac
authors.forename: Dietmar
authors.initials: D
authors.lastname: Glogar
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects*; D001610:Beta Particles / Q000627:therapeutic use; D019917:Blood Vessel Prosthesis Implantation; D001918:Brachytherapy; D017023:Coronary Angiography; D023903:Coronary Restenosis / Q000000981:diagnostic imaging / Q000209:etiology / Q000532:radiotherapy*; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011879:Radiotherapy Dosage; D012307:Risk Factors; D015607:Stents / Q000009:adverse effects*; D016896:Treatment Outcome