title: Effectiveness and determinants of the long-term beta intracoronary brachytherapy results.
abstract: BACKGROUND
  Effectiveness evaluation and search for the factors determining long-term results of beta intracoronary brachytherapy (ICBT) are of a special importance in an upcoming era of drug-eluting stents usage for a wide range of clinical indications: de novo and in-stent restenosis lesions.
  
  
  METHODS
  One hundred forty eight consecutive patients (59.6+/-9.6 years, 72% men) treated with beta ICBT for in-stent restenosis (ISR) or de novo lesions were studied. There were 135 ISR in 121 patients and 31 de novo lesions in 27 patients. Follow-up coronary angiography was performed in all patients after a mean of 8.9+/-4.5 months. Detailed qualitative and quantitative angiographic analysis of pre-, peri- and postprocedural as well as follow-up angiograms was performed.
  
  
  RESULTS
  Forty five percent of patients treated for de novo lesions were diabetic. Thirty five percent of all targets were located in vessels with a reference vessel diameter <2.5 mm. Furthermore, 77% of ISR lesions were in Class 1 according to the Mehran classification. The mean length of an irradiated segment was 37.6 mm. The overall recurrent restenosis rate was 28.3%. Multivariate analysis revealed that the reference vessel diameter and the presence of edge injury within the proximal 32P source dose-fall off were the only independent predictors of recurrent restenosis after ICBT (OR 0.46; 95%CI 0.24-0.89; p=0.021 and OR 2.55; 95%CI 1.23-5.25; p=0.011, respectively).
  
  
  CONCLUSIONS
  Recurrent restenosis after beta intracoronary brachytherapy treatment is negatively associated with the target vessel size. Presence of edge injury within the proximal 32P source dose-fall increases the frequency of recurrent renarrowing after ICBT. Our results indicate that target vessel size should be taken into account in optimising interventional strategy for ISR treatment: drug eluting stents versus intracoronary brachytherapy. Avoidance of edge injury within the proximal 32P source dose fall-off is strongly recommended while ICBT application.
authors.affiliation: 2nd Catheterization Laboratory, Institute of Cardiology, Warsaw-Anin, Poland.
authors.forename: Adam
authors.initials: A
authors.lastname: Witkowski
authors.forename: Łukasz
authors.initials: Ł
authors.lastname: Kalińczuk
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Chmielak
authors.forename: Jarosław
authors.initials: J
authors.lastname: Łyczek
authors.forename: Jerzy
authors.initials: J
authors.lastname: Pregowski
authors.forename: Maria
authors.initials: M
authors.lastname: Kawczyńska
authors.forename: Wojciech
authors.initials: W
authors.lastname: Bulski
authors.forename: Anna
authors.initials: A
authors.lastname: Kulik
authors.forename: Cezary
authors.initials: C
authors.lastname: Kepka
authors.forename: Mariusz
authors.initials: M
authors.lastname: Kruk
authors.forename: Stanisław
authors.initials: S
authors.lastname: Pszona
authors.forename: Witold
authors.initials: W
authors.lastname: Rózyłło
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D001918:Brachytherapy / Q000379:methods*; D017023:Coronary Angiography; D023903:Coronary Restenosis / Q000000981:diagnostic imaging*; D023921:Coronary Stenosis / Q000532:radiotherapy*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015607:Stents / Q000009:adverse effects*; D013997:Time Factors; D016896:Treatment Outcome