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Durable clinical benefit following Sr90 Beta irradiation therapy for in-stent restenosis in high-volume community practice.

Although randomized clinical trials have demonstrated efficacy of coronary irradiation versus placebo for the treatment of in-stent restenosis (ISR), durable long-term benefit in community practice is less well defined. From January 1, 2001, through June 30, 2002, consecutive percutaneous coronary intervention (n = 3,869) were analyzed at our center with a total of 330 patients undergoing coronary irradiation for ISR (53, Ir192; 12, P32; 265 Novoste Sr90). Novoste Sr90 was successfully performed in 265 of 270 (98%) of patients attempted by 10 operators. The mean patient age was 63 years (range 35 90) with 55% male (145/265) and 45% female (120/265). ISR anatomic subsets included multi-lesion (45/265; 17%), multi-vessel (27/265; 10.0%) and saphenous vein graft (16/265; 6.0%) interventions. At a mean follow-up of 10.5 2.8 (SD) months, fifty-three (20%) of the Novoste Sr90 treated patients had returned for symptoms requiring repeat angiography. Of these, 23 patients had repeat percutaneous coronary intervention (PCI) including 2 target site revascularizations (TSR), twelve non-TSR (distinct from the radiated segment of the target vessel), and 9 non-target vessel revascularizations (TVR). Coronary artery bypass surgery was performed in 11 total patients, 4 due to TSR, and 7 due to non-TVR. Clinical TSR was 2.3% (6/265) and TVR was 6.8% (18/265). In conclusion, the Novoste SR90 Beta-Cath System for the treatment of ISR is associated with a high procedural success rate and low TSR and TVR. Revascularization in follow-up is predominantly due to progressive disease outside the radiated segment and aggressive secondary prevention, especially prolonged anti-platelet therapy, appear critical to long-term procedural success.

Adult↗

Brachytherapy for refractory coronary artery restenosis.

A 76-year-old female patient complained of progressive episodes of chest and left arm pain and numbness, accompanied by a burning sensation in the left breast. The symptoms were nitroglycerine-responsive and consistent with her prior angina. Cardiac history included an initial percutaneous coronary intervention and 4 subsequent occurrences of restenosis in a stented area of the left anterior descending (LAD) coronary artery. Following a fifth restenosis of the LAD, the Novoste Beta-Cath Brachytherapy System was employed following balloon dilatation of the persistent recurrence. At 10 months post-brachytherapy, angiography revealed a patent LAD with no evidence of in-stent restenosis.

Aged↗

Intracoronary beta-irradiation with liquid rhenium-188 to prevent restenosis following pure balloon angioplasty: results from the TRIPPER-1 study.

BACKGROUND: Patients who receive percutaneous transluminal coronary angioplasty (PTCA) are often haunted by restenosis of the target vessel within 6 months. Intracoronary irradiation has been shown to alter the luminal narrowing response after balloon angioplasty. METHODS: The Taiwan Radiation in Prevention of Post-Pure Balloon Angioplasty Restenosis-I (TRIPPER-I) study evaluated the feasibility, safety, and 6-month angiographic restenosis with intracoronary irradiation after pure balloon angioplasty (POBA) of de novo and post-POBA restenotic lesions in native coronary arteries using a self-centering beta-emitter rhenium-188 (Re-188)-filled balloon. RESULTS: Forty patients received 14 Gy at a 0.5-mm tissue depth with a Re-188 solution-filled perfusion balloon catheter, and 25 control patients received 5-min inflation with a perfusion balloon catheter. There were no procedural complications or in-hospital or 30-day major adverse cardiac events. Six-month angiographic follow-up was performed on 39 Re-188 (97.5%) and 25 control patients (100%). The restenosis rate was 49% in the Re-188 and 56% in the control groups (p=0.62). The composite end-points of death, myocardial infarction, and target-vessel revascularization were 40% in the Re-188 group and 36% in the control group (p=0.80). CONCLUSIONS: Catheter-based radiotherapy after POBA of de novo and post-POBA restenotic lesions with a Re-188-filled balloon is feasible but was ineffective in reducing target lesion restenosis with a dose of 14 Gy delivered at a 0.5-mm tissue depth in this study.

Aged↗

Intracoronary beta-radiation for the treatment of patients at very high risk for recurrence of in-stent restenosis: a single center experience.

BACKGROUND: Intracoronary brachytherapy has significantly reduced the recurrence of in-stent restenosis. The aim of this study was to evaluate the feasibility, safety and efficacy of intracoronary beta-radiation in patients at very high risk for recurrence of in-stent restenosis. METHODS: We analyzed 42 patients with 50 lesions submitted to catheter-based beta-radiation (Beta-Cath System, Novoste Corporation, Norcross, GA, USA) for in-stent restenosis. Thirty-eight lesions were at the second restenosis, 8 at the third, and 4 at the fourth; a diffuse pattern was present in 78%. RESULTS: Balloon angioplasty was performed for 30 lesions (60%) and the cutting balloon technique for 20 (40%). In 12 lesions further 14 stents had to be deployed (28%). The delivery catheter was successfully positioned in 96% of the procedures. The mean dwell time was 179 +/- 50 s with a radiation dose ranging from 18.4 to 25.3 Gy, depending on the vessel size. A complete angiographic success without coronary dissection and without any additional stenting after radiation delivery was achieved in 86%. At follow-up (7.2 +/- 2.1 months), the overall restenosis rate was 30.4% (14 lesions). A recurrence was detected in 1/11 lesions with initial focal pattern and in 13/39 lesions with initial diffuse pattern. The restenosis rate was higher in patients in whom a geographic miss had occurred (p < 0.05 vs lesions without geographic miss) and in those in whom a new stent had been deployed (p < 0.05 vs lesions treated without a stent). CONCLUSIONS: Brachytherapy reduces the in-stent restenosis rate in patients who are at very high risk of recurrence. The restenosis pattern, geographic miss and new stent deployment seem to be negative prognostic factors for recurrence of restenosis.

Aged↗

[Beta-radiation exposure at the finger tips during the radionuclide synovectomy].

AIM: The radiation synovectomy is a widespread therapeutic option in rheumatoid arthritis. However, data for the beta-radiation exposure are rare. The aim of this study was to determine the personal dose equivalent H(P) (0.07) of the skin of the hands. METHODS: Thermo-luminescence detectors (TLDs) were attached at all fingertips of the therapist, the radiochemist and the nurse. In summary, the measurement of beta-exposure occurred in 155 joints at 6 days with different radio-nuclides ((169)Er, (186)Re, (90)Y). RESULTS: The greatest beta exposure were show at the forefinger (L-Ff) and thumb (L-Th) of the left hand, with which the therapist (right hander) fixed the injection needle. In 52 treated finger-joints (1204 MBq (169)Er), 29 treated large joints (2405 MBq (186)Re) and 15 treated knees (3100 MBq (90)Y) we found a cumulative beta exposure over all radionuclides of 190 mSv at L-Ff and 48 mSv at L-Th. The specific beta exposure for the individual radio-nuclides showed beta exposures of 0.56 mu Sv/MBq for (169)Er and 1.52 mu Sv/MBq for (186)Re-186 at the L-Ff. With using a manipulator the beta-exposure ((90)Y) could reduced from 22,09 to 0.42 mu Sv/MBq at the L-Ff. The greatest beta exposures for the radiochemist was 119 mSv at the L-Ff for all radionuclides. CONCLUSION: In usual techniques of radiation synovectomy the (90)Y produced the greatest part of radiation exposure. Especially at the L-Ff it might exceed the German limit for the official dosimetry service at the skin ( section sign 55 Strl-SchV). Using a holding forceps we can keep the legal rules and can reduce considerably the beta exposure.

Arthritis, Rheumatoid↗

Treatment of bifurcation in-stent restenotic lesions with beta radiation using strontium 90 and sequential positioning pullback technique: procedural details and clinical outcomes.

BACKGROUND: In-stent restenotic lesions have been problematic for many patients with the need for multiple repeat percutaneous coronary interventions (PCI). The need for repeat PCI has been significantly reduced in patients since the advent of vascular brachytherapy. In-stent restenosis resulting in bifurcation presents even more of a challenge. The use of radiation therapy for the treatment of this kind of lesion has not yet been reported. The purpose of this paper is to present five cases of radiation therapy in bifurcation in-stent restenotic lesions using the intraluminal beta radiation catheter delivery system (Beta-Cath System, Novoste Corporation, Norcross, Georgia). METHODS: We reviewed the database of patients enrolled in our Compassionate Use Registry between August 1999 and April 2002. The data is reported for 5 patients who received radiation in both branches of bifurcation lesions with the Beta-Cath catheter system. RESULTS: The mean diameter of the vessels was 3.1 mm 0.5 mm. The dose administered was from 18.3 to 23 Gy, with an overlap of 3.3 to 10.3 mm; the hinge angle between the branches went from 43.3 to 65.4 . Angiographic follow-up was obtained at 6 months in 4 patients, with a single patient showing a focal (< 5 mm) edge lesion treated by balloon angioplasty (TVR no TLR). No aneurysms or zones of ectasia were noted. CONCLUSION: Beta radiation with the Beta-Cath catheter system appears to be safe, secure and clinically useful in in-stent restenotic bifurcation lesions.

Angioplasty, Balloon↗

The state of the microcirculatory bed after total ischaemia of the brain. An experimental ultrastructural study.

The study was focused on the changes in morphological structure of cerebral microcirculation after two stages of 7 min dog's total brain ischaemia followed by 24 recirculation. In the first experimental group (brain blood pressure 2.5-3.0 kPa), there was observed ultrastructural picture of damaged microvessels, including dilated and irregularly shaped lumens, thick finger-like endothelial processes, dark osmiophilic cytoplasm of the endothelial cells with light spaces, clusters of ribosomal structures, impairment of endoplasmic reticulum and mitochondria, dilated tight junctions, irregular and thickened basement membranes. The alteration of astrocytes consisted of accumulation of beta-glycogen particles and lipofuscin and altered lysosomal structures. On the other hand, in the second experimental group (brain blood pressure 1.0-1.5 kPa) the signs of impaired microcirculation were found. Type A pattern of vessel damage was delineated by dilated capillary lumen, despite the presence of marked perivascular oedema. Type B represented the no-reflow phenomenon. Type C was defined by a conspicuous lobular nucleus of endothelial cells obstructing the lumen of the capillary. Type D was characterized by ischemically damaged erythrocytes, despite the adequate perfusion fixation. Finally, type E included necrotic endothelial cells and endothelial blebs.

Animals↗