Intracoronary radiotherapy with a 188Rhenium liquid-filled angioplasty balloon system in in-stent restenosis: a single-center, prospective, randomized, placebo-controlled, double-blind evaluation.

BACKGROUND: In cases of in-stent restenosis, intracoronary radiotherapy with beta-emitters and gamma-emitters has been shown to reduce the risk of repeat restenosis. The present randomised, placebo-controlled study addresses the question of whether intracoronary radiotherapy applied by the easy-to-handle Rhenium liquid-filled angioplasty balloon system is also able to reduce the angiographic re-restenosis rate in stents. METHODS AND RESULTS: At our center, from May 2000 to December 2003, 165 patients (mean age 64+/-10, median 65 years; 127 men, 38 women) with symptomatic in-stent restenosis underwent either intracoronary brachytherapy or sham procedure. Index clinical and angiographic parameters were largely comparable in both groups. Radiation therapy was performed with a standard percutaneous transluminal coronary angioplasty (PTCA) balloon catheter inflated with liquid Rhenium in the redilated in-stent restenosis for 240-890, mean 384+/-125 s with low pressure (3 atm) in order to reach 30 Gy at 0.5 mm depth of the vessel wall. In 82 patients, intracoronary radiotherapy was carried out without complications, but one of the 83 patients who underwent sham procedure suffered small myocardial infarction. During follow-up, stent thrombosis with subsequent non-Q-wave myocardial infarction occurred in one patient in each group (6 days and 8 months after the procedure, respectively). At 6 months after the index procedure, repeat angiography was performed in 156 of the 164 patients with successful procedure (rate 95%): restenosis (stenosis >50% in diameter) or reocclusion was observed in only 19 of 78 (=24%) patients of the radiation but in 31 of 78 (=40%) patients of the sham procedure group (P=0.04). Event-free survival (free of death, myocardial infarction, target vessel revascularization) at 1 year was 87% for patients being radiated and 74% for patients having undergone sham procedure (P=0.05). CONCLUSIONS: Intracoronary radiation therapy with the liquid-filled beta-emitting Rhenium balloon is not only easy to perform, safe, and comparably inexpensive but also an effective option to prevent repeat restenosis and the need for target vessel revascularization in cases of in-stent restenosis.

Results of angioplasty (with or without stent) at the site of a narrowed coronary anastomosis of the left internal mammary artery graft or via the internal mammary artery.

During the past 6 years, 50 patients underwent percutaneous transluminal coronary angioplasty (PTCA) of a narrowed coronary anastomosis of a left internal mammary artery (LIMA) graft or PTCA of a left anterior descending coronary artery stenosis via LIMA grafts at the investigators' institution. The success rate was high at 88%. Thirty-four of the 44 successfully treated patients (77%) underwent repeat angiography, which showed restenosis in 14 patients (41%). In cases of stent implantation at the coronary LIMA graft anastomosis angioplasty site, the restenosis rate was 80%, but it was only 14% in cases of pure balloon dilation (p = 0.001). Therefore, in cases of coronary LIMA graft anastomosis, stent implantation should be avoided, because it implicates an excessively high restenosis rate.

Intracoronary radiotherapy with a (188)rhenium liquid-filled PTCA balloon system in in-stent restenosis: acute and long-term angiographic results, as well as 1-year clinical follow-up.

BACKGROUND: Intracoronary radiotherapy with beta- and gamma-emitters has been shown to reduce the risk of restenosis after balloon angioplasty and after coronary stenting. The present study addresses the question whether intracoronary radiotherapy using the (188)rhenium liquid-filled PTCA balloon system is feasible, safe and effective in cases of in-stent restenosis. Acute and long-term angiographic results as well as clinical events within 1 year after the procedure were evaluated. METHODS AND RESULTS: From September 1999 to April 2000, 41 patients (mean age 60+/-10 years, 33 male, 8 female) with symptomatic in-stent restenosis underwent repeat PTCA and immediate intracoronary brachytherapy. After successful repeat PTCA (residual stenosis less than 30% in diameter), a second standard PTCA catheter was inflated with liquid (188)rhenium in the redilated in-stent restenosis for 315-880, mean 540+/-155 s with low pressure (3 atm) in order to reach 30 Gy at 0.5 mm depth of the vessel wall. In all patients with successful reintervention, intracoronary radiotherapy was unproblematically performed; in 16 patients, 21 new stents were implanted during the procedure-either immediately before or after radiation therapy. During follow-up, four episodes of stent thrombosis with subsequent myocardial infarction occurred in three patients (8 days, 37 days, 5 months and 6 months after the procedure, respectively). This complication was seen exclusively in patients with newly implanted stents. One patient of the stent group died suddenly 46 days after the procedure. All 40 surviving patients underwent repeat angiography in cases of repeat angina or routinely 6 months after brachytherapy, respectively. In the redilated target vessels without new stenting, restenosis (stenosis >50% in diameter) or reocclusion was observed in only 5 of 25 (=20%) cases, but in the restented target lesions, in 10 of 15 (=67%). Event-free survival (death, myocardial infarction, TVR) at 1 year after repeat dilatation and subsequent brachytherapy was 80% for patients not newly stented, but only 44% for patients with new stents. CONCLUSIONS: Intracoronary radiation therapy with the liquid-filled beta-emitting (188)rhenium balloon is a safe and effective therapy in cases of in-stent restenosis. The positive effect of irradiation, however, is abolished if a new stent is needed. In the not newly stented patients, 1-year follow-up is encouraging.