ABSTRACT
Treatment of in-stent restenosis after implantation of a drug-eluting stent is a critical issue. We provide the first report of the use of intravascular radiation therapy for this purpose in a 73-year-old diabetic patient stented for small-vessel bifurcation; treatment of Cypher diffuse in-stent restenosis with (32)P brachytherapy proved successful at clinical and angiographic follow-up at 7 months. This finding should encourage systematic studies on the safety and efficacy of IRT in this problematic setting.
Subject(s)
Brachytherapy/methods , Coronary Restenosis/radiotherapy , Stents , Aged , Blood Vessel Prosthesis Implantation/instrumentation , Coronary Angiography , Coronary Restenosis/diagnostic imaging , Coronary Vessels/radiation effects , Coronary Vessels/surgery , Follow-Up Studies , Humans , Male , Myocardial Infarction/surgery , Phosphorus Radioisotopes/therapeutic use , Prosthesis FailureABSTRACT
The objective of this study was to determine the safety and efficacy of (32)P beta-brachytherapy in totally occlusive in-stent restenosis (ISR). Patients with occlusive ISR were generally excluded from the randomized clinical trials on intracoronary brachytherapy (utilizing either gamma- or beta-sources) that have shown reductions in restenosis rate and need for revascularization procedures. We analyzed short- and long-term effects of (32)P beta-brachytherapy (20 Gy) in 27 patients (28 lesions) with occlusive ISR and 84 (99 lesions) patients with nonocclusive high-risk ISR. The primary outcome measure was frequency of in-lesion angiographic binary restenosis at 7 months. Secondary endpoints were rates of major adverse cardiac events (MACE), target vessel revascularization (TVR), clinically driven TVR, and target lesion revascularization (TLR). (32)P beta-brachytherapy was feasible and safe and provided similar postprocedural angiographic results in the two clinically comparable groups. However, the 7-month binary restenosis rate was higher in the occlusive group, as were the MACE and late total occlusion rates. Multivariate logistic analysis of the overall population indicated occlusive pattern to be the only independent predictor of angiographic restenosis. In both groups, recurrent lesions most often showed a focal pattern with significant reduction of length. Although safe and effective in high-risk ISR, (32)P brachytherapy at 20 Gy does not appear to be sufficient to avoid long-term restenosis in patients with occlusive lesions. Further studies should determine the most suitable source and dosage of brachytherapy for patients with occlusive ISR.
Subject(s)
Brachytherapy , Coronary Angiography , Coronary Restenosis/diagnostic imaging , Coronary Restenosis/radiotherapy , Phosphorus Radioisotopes/therapeutic use , Radiopharmaceuticals/therapeutic use , Stents , Aged , Beta Particles/therapeutic use , Blood Vessel Prosthesis Implantation , Brachytherapy/methods , Female , Follow-Up Studies , Humans , Male , Middle Aged , Multivariate Analysis , Prospective Studies , Time Factors , Treatment OutcomeABSTRACT
BACKGROUND: The effectiveness of coronary radiation therapy for the treatment of in-stent restenosis (ISR) has been established in several randomized clinical trials. The efficacy of this treatment in the general population is less well established. METHODS AND MATERIALS: We report our experience in 118 consecutive patients with nonselected high-risk ISR who had undergone successful percutaneous coronary intervention and brachytherapy with (32)P beta-irradiation and who were prospectively enrolled in a quantitative angiographic and clinical follow-up protocol at 7 months after the index procedure. The aim of this study was to investigate the independent predictor of angiographic restenosis after (32)P brachytherapy treatment. RESULTS: Of the patients, 28.8% were diabetics. The mean lesion and mean radiated lengths were, respectively, 30.1 +/- 17.2 and 43.8 +/- 16.9 mm. The ISR pattern was diffuse in 96% of the treated lesions; in particular, 22.1% presented an occlusive pattern and 37.1% a proliferative pattern. At follow-up angiographic, restenosis and major adverse cardiac events (MACE) rates were, respectively, 20.8% and 29.6%. The univariate predictors of angiographic restenosis were procedural geographic miss, pattern IV ISR, manual pullback maneuver of the radiation source, preprocedural lesion percentage stenosis and preprocedural lesion MLD. At logistic regression analysis, only geographic miss and pattern IV ISR were independent predictors of post intracoronary radiation therapy (IRT) angiographic restenosis. CONCLUSION: These data indicate that 7-month angiographic restenosis after (32)P IRT in complex patients with ISR is not a frequent event and is predicted mainly by an occlusive lesion at baseline and by procedural geographical miss.
Subject(s)
Brachytherapy/adverse effects , Brachytherapy/methods , Coronary Restenosis/radiotherapy , Phosphorus Radioisotopes/therapeutic use , Stents , Aged , Coronary Angiography/methods , Coronary Restenosis/diagnostic imaging , Coronary Restenosis/mortality , Female , Follow-Up Studies , Humans , Male , Myocardial Infarction/etiology , Myocardial Revascularization/methods , Predictive Value of Tests , Prospective Studies , Risk Factors , Survival Analysis , Treatment Failure , Treatment OutcomeABSTRACT
BACKGROUND: The aim of the study was to evaluate, on single center prospective data, long-term angiographic and clinical results of intracoronary beta (32P) brachytherapy in "real world" patients with high-risk in-stent restenosis lesions. METHODS: Sixty-nine consecutive patients (77 lesions) with high-risk in-stent restenosis (mean lesion length 30.3 +/- 16.1 mm, pattern III-IV 57.2%, diabetes 33.3%) treated with percutaneous dilation procedures and beta-radiation therapy, underwent 7-month clinical and angiographic follow-up. RESULTS: One patient (1.4%) presented with procedural non-Q wave myocardial infarction. At a mean follow-up of 7 +/- 1.5 months, death was observed in 1 patient (1.4%) and non-Q wave myocardial infarction in 3 (4.3%) (in 2 patients, who prematurely discontinued antiplatelet therapy, caused by late coronary thrombosis). Seven-month binary angiographic restenosis occurred in 20 lesions (25.9%) (in-stent restenosis 11.6%). Target lesion and target vessel revascularization occurred in 20 (28.9%) and 21 (30.4%) patients. At follow-up only 12 (17.3%) patients presented with CCS class III-IV angina. After intracoronary beta brachytherapy angiographic restenosis occurred regardless of the vessel size, lesion length and ostial location. On the contrary a high restenosis rate was documented in obstructive lesions. CONCLUSIONS: As applied in routine clinical practice, radiation therapy is safe and effective in the treatment of high-risk in-stent restenosis. In spite of all that, total occlusion at baseline predicts late angiographic restenosis.
Subject(s)
Brachytherapy/methods , Coronary Restenosis/radiotherapy , Stents , Aged , Angioplasty, Balloon, Coronary/methods , Beta Particles/therapeutic use , Female , Follow-Up Studies , Humans , Male , Middle Aged , Phosphorus Radioisotopes , Prospective Studies , Retrospective StudiesABSTRACT
We report a case of obstructive in-stent restenosis in a diffusely diseased saphenous vein graft complicated by a non-ST-elevation myocardial infarction. With tirofiban infusion, the extensively occluded saphenous bypass was reperfused, establishing a TIMI flow 3, and then entirely irradiated with a beta source (32P) without any complication. At 7 months the patient was asymptomatic and the control angiogram did not reveal any restenosis. In conclusion, 32P beta brachytherapy may be extremely effective not only in case of native vessel in-stent restenosis but also in cases of high-risk vein graft in-stent restenosis.