title: Chronic total occlusion due to diffuse in-stent restenosis: is brachytherapy the solution?
abstract: Percutaneous coronary intervention of chronic total occlusions (CTO) is associated with a significantly higher incidence of reocclusion and restenosis compared with non-total occlusions. Randomized and observational trials have demonstrated the effectiveness of intracoronary brachytherapy (ICBT) for the prevention of recurrent in-stent restenosis. However, limited data are available on the effectiveness of ICBT in patients with totally occluded in-stent restenosis. The authors assessed the long-term outcome of patients treated with intracoronary gamma radiation for totally occluded in-stent restenotic lesions. Percutaneous coronary intervention and subsequent catheter-based irradiation with iridium-192 was performed in 100 patients (103 vessels) with diffuse in-stent restenosis. At baseline, CTO of the target vessel at the site of the stent was present in 15 vessels (14.5%). Follow-up data were collected during follow-up visits and from telephone interviews. Repeat coronary angiography was performed in symptomatic patients with clinical restenosis. Clinical and angiographic characteristics were similar between the two groups, although there was a trend towards more unstable angina at the index procedure in CTO patients (66.7% versus 41.4%; p = 0.12) compared with patients without non-total occlusions. A higher percentage of patients (53.3%) with CTO required longer radiation sources (14 seeds, covering a length of 55 mm), compared with 23.9% of patients with non-total occlusion (p = 0.04). With a mean follow-up period of 47.5 +/- 24.0 months, major adverse cardiac events (MACE) were observed in 10 of 15 patients (66.7%) with CTO compared with 25 out of 88 patients (28.4%) without CTO (p = 0.009). According to multivariate analysis, total occlusion of the target vessel at baseline was the single independent predictor of MACE at one-year follow-up (relative risk 16.2, 95% confidence interval 4.2-62.9; p < 0.0001). This study shows that the use of gamma radiation for the prevention of recurrence of in-stent restenosis in patients with CTO does not seem to be as effective as in patients with non-total occlusions. Furthermore, CTO was an independent predictor of worse outcome at long-term follow-up in this study.
authors.affiliation: Department of Invasive Cardiology, Rambam Medical Center and Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
authors.forename: E
authors.initials: E
authors.lastname: Nikolsky
authors.forename: L
authors.initials: L
authors.lastname: Gruberg
authors.forename: E
authors.initials: E
authors.lastname: Rosenblatt
authors.forename: E
authors.initials: E
authors.lastname: Grenadier
authors.forename: M
authors.initials: M
authors.lastname: Boulos
authors.forename: Z
authors.initials: Z
authors.lastname: Bernstein
authors.forename: A
authors.initials: A
authors.lastname: Huber
authors.forename: R
authors.initials: R
authors.lastname: Gitman
authors.forename: R
authors.initials: R
authors.lastname: Bar-Deroma
authors.forename: W
authors.initials: W
authors.lastname: Markiewicz
authors.forename: R
authors.initials: R
authors.lastname: Beyar
mesh_terms: D001918:Brachytherapy / Q000379:methods*; D017023:Coronary Angiography; D023903:Coronary Restenosis / Q000532:radiotherapy*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007496:Iridium Radioisotopes / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D012042:Registries / Q000706:statistics & numerical data; D015607:Stents; D013997:Time Factors
chemical_list: D007496:Iridium Radioisotopes