经皮腔内β-射线放射疗法与切割球囊成形术联合治疗冠状动脉支架内再狭窄

目的　旨在研究经皮冠状动脉 (冠脉 )内 β 射线放射疗法 (β 放疗 ,Novoste)与切割球囊成形术 (CBA)联合治疗支架内再狭窄 (ISR)的疗效及其安全性。方法　冠脉内支架置入术后ISR >70 %的病人 2 95例 [男性 2 0 5例 ,女性 90例 ,年龄 (5 9 76± 10 83)岁 ],其中 112例均行CBA联合 β 放疗为 β 放疗组 (n =112 ) ,183例单独采用CBA(89例 )或普通球囊扩张成形术 (94例 )为对照组 (n =183)。弥漫性长病变ISR者β 放疗先照射病变远段 ,再回撤导管照射病变近段。所有病例术前、术后即刻及术后随访期行冠脉造影 ,分析病变长度、最小管腔直径 (MLD)、参照管腔直径 (RLD)和管腔直径狭窄百分比 (DS)。随访靶血管再次成形率 (TVR)和主要不良心血管事件 (MACE)发生率。结果　术前及术后即刻两组病人的冠脉造影结果差异无显著性。随访期 (6 3± 1 6月 ) β 放疗组的MLD大于对照组 ,DS小于对照组 ,P <0 0 5。β 放疗组与对照组的心绞痛、心肌梗死及死亡率相似 ,差异无显著性(心绞痛为 10 %vs17% ,心肌梗死为 1%vs 2 % ,死亡率为 0 %vs2 % ) ,但β 放疗组的TVR和MACE明显低于对照组 (TVR为 5 %vs 16 % ,MACE为 10 %vs 2 5 % ,P <0 0 5 )。β 放疗组 2 8例 (2 6 % ,2 8 10 6 )弥漫性长病变ISR ,回撤 β 放疗导管分     

切割球囊成形术与经皮腔内β-射线放射疗法联合治疗冠状动脉支架内再狭窄

目的观察切割球囊成形术(CBA)与经皮冠状动脉(冠脉)内β-射线放射疗法(β-放疗)联合治疗支架内再狭窄(ISR)的疗效及其安全性.方法冠脉内支架置入术后ISR>70%的患者295例,男性205例,女性90例,平均年龄(59.76±10.83)岁,其中112例均行CBA联合β-放疗作为β-放疗组(n=112),183例单独采用CBA(89例)或普通球囊扩张成形术(94例)为对照组(n=183).弥漫性长病变ISR者回撤β-放疗导管分段照射.所有患者术前、术后即刻及术后随访期行冠脉造影,随访靶血管血运重建(TVR)和主要不良心血管事件(MACE)发生率.结果两组患者的术前及术后即刻冠脉造影结果差异无显著性.随访期(6.3±1.6) 月β-放疗组的最小管腔直径大于对照组,管腔直径狭窄百分比小于对照组,P<0.05.β-放疗组与对照组的心绞痛、心肌梗死及病死率相似(心绞痛为10%比17%,心肌梗死为1%比2%,病死率为0%比2%), 但β-放疗组的TVR和MACE明显低于对照组(TVR为5%比16%,MACE为11%比21%,P<0.05).β-放疗组28例(25%)弥漫性长病变ISR,分段照射后随访TVR和MACE无增加.结论冠脉内β-放疗和CBA相结合治疗ISR安全、有效,TVR和MACE明显降低.采用回撤β-放疗导管技术可以有效地治疗弥漫性长病变ISR.     

Treatment of diffuse in-stent restenosis with rotational atherectomy followed by radiation therapy with a rhenium-188-mercaptoacetyltriglycine-filled balloon

OBJECTIVES: This study was done to evaluate the feasibility and efficacy of beta-radiation therapy with a rhenium-188-mercaptoacetyltriglycine ((188)Re-MAG(3))-filled balloon after rotational atherectomy for diffuse in-stent restenosis (ISR). BACKGROUND: Rotational atherectomy has been shown to be safe and efficient for the treatment of ISR, but the recurrence rate is still high. Intracoronary beta-irradiation after rotational atherectomy may be a reasonable approach to prevent recurrent ISR. METHODS: Fifty consecutive patients with diffuse ISR (length >10 mm) in native coronary arteries underwent rotational atherectomy and adjunctive balloon angioplasty, followed by beta-irradiation using a (188)Re-MAG(3)-filled balloon catheter. The radiation dose was 15 Gy at a depth of 1.0 mm into the vessel wall. RESULTS: The mean lengths of the lesion and irradiated segment were 25.6 +/- 12.7 mm and 37.6 +/- 11.2 mm, respectively. Radiation was delivered successfully to all patients, with a mean irradiation time of 201.8 +/- 61.7 s. No adverse event, including myocardial infarction, death or stent thrombosis, occurred during the follow-up period (mean 10.3 +/- 3.7 months), and nontarget vessel revascularization was needed in one patient. The six-month binary angiographic restenosis rate was 10.4%, and the loss index was 0.17 +/- 0.31. CONCLUSIONS: Beta-irradiation using a (188)Re-MAG(3)-filled balloon after rotational atherectomy is safe and feasible in patients with diffuse ISR, and it may improve their clinical and angiographic outcomes. Further prospective, randomized trials are warranted to evaluate the synergistic effect of debulking and irradiation in patients with diffuse ISR.     

Comparison of angiographic and clinical outcomes between rotational atherectomy versus balloon angioplasty followed by radiation therapy with a rhenium-188-mercaptoacetyltriglycine-filled balloon in the treatment of diffuse in-stent restenosis

BACKGROUND: The purpose of this study was to compare the efficacy of rotational atherectomy (RA) with simple balloon angioplasty, prior to beta-radiation therapy with a rhenium-188-mercaptoacetyltriglycine (188Re-MAG3)-filled balloon for diffuse in-stent restenosis (ISR). METHODS: After completing 50 cases with RA prior to beta-radiation (Group I), we performed optimal balloon angioplasty followed by beta-radiation in the next 53 consecutive patients (Group II) for the treatment of diffuse ISR. The radiation dose was 15 Gy at a depth of 1.0 mm into the vessel wall. RESULTS: The baseline clinical and angiographic characteristics were similar between the two groups. The mean length of the lesion was 25.6+/-12.7 mm in Group I and 22.9+/-8.6 mm in Group II (p=0.26). Radiation was successfully delivered to all patients, with a mean irradiation time of 179+/-55 s. The 6-month angiographic restenosis rate was 10% (5/50) in Group I versus 33% (17/51) in Group II (p=0.007). No adverse event including myocardial infarction, death, or stent thrombosis occurred during the 1-year follow-up period. The risk of a target lesion revascularization or a major adverse cardiac event was significantly lower in Group I than in Group II (two patients in Group I vs. nine patients in Group II; OR, 0.20; 95% CI, 0.04-0.96; p=0.04). CONCLUSION: Concomitant treatment with rotational atherectomy and beta-irradiation using a 188Re-MAG3-filled balloon for diffuse ISR has a synergistic effect, in terms of 6-month angiographic restenosis and 1-year cardiac event-free survival.     

Two-year clinical follow-up results of intracoronary radiation therapy with rhenium-188-diethylene triamine penta-acetic acid-filled balloon.

We investigated the 2-year clinical follow-up results as well as 6-month angiographic and clinical follow-up results of intracoronary radiation therapy using a rhenium-188-diethylene triamine penta-acetic acid ((188)Re-DTPA)-filled balloon system. The study comprised of 161 patients with significant de novo (83%) or in-stent restenosis (17%) lesions. Irradiation to deliver 17.6 Gy at a depth of 1.0 mm into the vessel wall was carried out after successful intervention. At 6-month follow-up, binary restenosis developed with significantly lower frequency in the radiation group than in the control group (24.3% vs. 46.3%; P = 0.009), although target lesion revascularization rate did not show significant benefit. At 2-year follow-up, cumulative target lesion revascularization rate was not significantly different between radiation group (n = 86) and control group (n = 75; 20.0% vs. 26.0%; P = 0.368). The rate of major adverse cardiac events including death, myocardial infarction, and target lesion revascularization did not show significant difference between two groups either (22.3% vs. 30.1%; P = 0.266). In conclusion, although significant reduction in restenosis rate was noted at 6-month angiographic follow-up, intracoronary radiation therapy mostly in patients with de novo lesion did not show significant clinical benefit in 6-month and 2-year follow-up results. The benefit was noted only in a small subgroup of patients with in-stent restenosis.     

Percutaneous transluminal coronary angioplasty restenosis: potential prevention with laser balloon angioplasty

Restenosis after percutaneous transluminal coronary angioplasty may result primarily from the combination of a thrombogenic surface and local flow separation produced by disruption of the arterial wall and lumen. Elastic recoil and, perhaps, cellular proliferation further contribute to luminal compromise after percutaneous transluminal coronary angioplasty. Laser balloon angioplasty, performed during the final inflation of an otherwise conventional balloon angioplasty procedure, uses the coagulative properties of Nd:YAG laser radiation to weld together disrupted tissue elements thermally, to reduce elastic recoil and to destroy viable arterial tissue. Studies in human postmortem atheromatous arteries and in animal models in vivo indicate that laser balloon angioplasty, by creating a lumen that approximates the size and smooth cylindrical shape of the balloon, should be effective in the treatment of important causes of restenosis.     

Intravascular ultrasound analysis of nonstented adjacent segments in diffuse in-stent restenosis treated with radiation therapy with a rhenium-188-filled balloon.

The effects of beta-radiation therapy on nonstented adjacent segments in in-stent restenosis have not been sufficiently evaluated. beta-radiation therapy for in-stent restenosis was performed with a (188)Re-MAG(3)-filled balloon. We evaluated the effects of beta-radiation therapy on nonstented adjacent segments in in-stent restenosis by intravascular ultrasound (IVUS) analysis in 50 patients who received radiation therapy vs. 9 control patients. The changes (Delta = follow-up - postintervention) of the external elastic membrane (EEM), the lumen, and other IVUS variables were compared between the segments that received radiation therapy and the control segments. The significant differences between the two groups were as follows: Delta EEM area was 0.3 mm(2) in the radiation vs. -1.0 mm(2) in the control (P = 0.005) and Delta lumen area was 0.2 mm(2) vs. -1.3 mm(2), respectively (P < 0.001). In conclusion, compared with the changes of vessel shrinkage in the control group, significant vessel enlargement occurred in the nonstented adjacent segments that received radiation therapy.     

Three-year clinical follow-up results of intracoronary radiation therapy using a rhenium-188-diethylene-triamine-penta-acetic-acid-filled balloon system.

BACKGROUND: Intracoronary radiation therapy (IRT) prevents recurrent in-stent restenosis, but its long-term safety and efficacy remain uncertain. In the present study, the long-term clinical outcome of IRT using the rhenium-188 ((188)Re)-filled balloon system was evaluated. METHODS AND RESULTS: After successful catheter-based treatment of either a de novo or restenotic lesion, 187 patients were randomly assigned to either the radiation (N=104) or the control (N=83) group. The (188)Re-filled balloon system was designed to deliver 17.6 Gy to 1.0-mm tissue depth. Angiographic restenosis was significantly reduced with IRT at 9 months (18.9% vs 45.9%, p<0.001), but the incidence of major adverse cardiac events (MACE) including death, myocardial infarction, and target-vessel revascularization (TVR) by 3 years showed no difference. Lack of clinical benefit might be related to TVR caused by geographic miss (6/22, 28.6%), balloon-induced unhealed dissection (3/22, 13.6%) and late thrombosis (2/22, 9.1%). In the restenotic subgroup (N=39), the MACE rate within 3 years was significantly reduced with IRT (14.3% vs 54.5%, p=0.01). CONCLUSIONS: IRT using the (188)Re -filled balloon system is safe and technically feasible. Although IRT failed to show favorable outcomes for de novo lesion, the clinical benefits for restenotic lesions seem durable for 3 years. Furthermore, preventing geographic miss and dissection might improve long-term outcomes.     

Intracoronary irradiation markedly reduces restenosis after balloon angioplasty in a porcine model

Objectives. This study examined the effects of intracoronary Irradiation on neointimal proliferation after overstretch balloon angioplasty in a normolipemic swine model of restenosis.Background. Restenosis after percutaneous transluminal coronary angioplasty represents, in part, a proliferative response of vascular smooth muscle at the site of injury. We have previously shown that ionizing radiation, delivered by means of an intracoronary source, causes focal medial fibrosis. We therefore hypothesized that ntracoronary irradiation delivered at the time of balloon angtoplasty might impair the restenosis process.Methods. Nineteen juvenile swine underwent coronary angiography; a segment of the coronary artery was chosen as a target for balloon injury. In 10 swine, a ribbon of iridiun-192 was positioned at the target segment, and 2,000 cGy was delivered at the vessel wall. Subsequently, overdilation balloon angioplasty was perfromed at the irradiated segment. In nine control swine, overdilation balloon angioplasty was performed without previous irradiation. Eighteen animals survived and were killed at 30 days. Histopathologic analysis was performed by a pathologist in blinded manner. The area of maximal lumen compromise within the target segment was analyzed by computer-assisted planimetry.Results. In the control group, mean (± SD) neointimal area was 0.84 ± 0.60 mm²compared with that in the irradiated group, 0.24 ± 0.13 mm²(p = 0.01). In the control group, mean percent area stenosis was 47.6 ± 20.7%, whereas that in the irradiated group was 17.6 ± 10.5% (p = 0.001). This represents a 71.4% reduction in neointimal area and a 63.0% reduction in percent area stenosis in the irradiated group. Adjacent coronary segments and surrounding myocardium were unaffected.Conclusions. Intracoronary irradiation (2,000 cGy) delivered to a target porcine coronary segment before balloon overdilation markedly reduces neointima formation at 30 days and thus significantly impairs the restenosis process.     

Repeat intracoronary beta-brachytherapy using a rhenium-188-filled balloon catheter for recurrent restenosis in patients who failed intracoronary radiation therapy.

BACKGROUND: Conventional percutaneous coronary intervention (PCI) in restenotic lesions after brachytherapy failure is associated with a high recurrence rate of restenoses and revascularizations. Intracoronary brachytherapy using a liquid rhenium-188-filled balloon in de novo or restenotic lesions safely and effectively reduced restenosis rates. We report clinical and angiographic data regarding the safety and efficacy of rhenium-188 brachytherapy in restenoses after brachytherapy failure. METHODS: Fourteen patients with restenosis after brachytherapy failure received rhenium-188 beta-brachytherapy. Follow-up was performed angiographically after 6 months and clinically after 12 months. Primary clinical endpoint was the incidence of major adverse cardiac events (MACE) defined as any death, myocardial infarction or repeat revascularization in the target vessel within 12 months. Secondary angiographic endpoints were the binary restenosis rate and late loss in the total segment including edge effects at 6 months. RESULTS: The prescribed dose of 22.5 Gy (n=12) or 30 Gy (n=2) was successfully delivered in all patients. In two lesions, a bare-metal stent was implanted. The mean length of the irradiated segment was 40.0+/-15.7 mm. The mean diameter of the irradiation balloon was 2.96+/-0.37 mm. Angiographic follow-up was done in 13 of 14 patients. There was no edge stenosis or coronary aneurysm. Within the total segment, late loss was 0.39+/-0.64 mm and late loss index was 0.18+/-0.40 with a binary restenosis rate of 23%. Twelve months' clinical follow-up was available in all patients, which showed a MACE rate of 7% due to one target lesion revascularization (TLR). CONCLUSIONS: Intracoronary beta-brachytherapy with a liquid rhenium-188-filled balloon in restenoses after intracoronary radiation therapy failure including 12 months combined antiplatelet therapy is safe with respect to vessel thrombosis, late coronary occlusion or aneurysm formation. With limited use of stenting, angiographic and clinical follow-up for repeat brachytherapy were favorable and it is associated with low restenosis and target vessel revascularization rate.     

Cutting balloon angioplasty for the prevention of restenosis: results of the Cutting Balloon Global Randomized Trial

The cutting balloon (CB) is a specialized device designed to create discrete longitudinal incisions in the atherosclerotic target coronary segment during balloon inflation. Such controlled dilatation theoretically reduces the force needed to dilate an obstructive lesion compared with standard percutaneous transluminal coronary angioplasty (PTCA). We report a multicenter, randomized trial comparing the incidence of restenosis after CB angioplasty versus conventional balloon angioplasty in 1,238 patients. Six hundred seventeen patients were randomized to CB treatment, and 621 to PTCA. The mean reference vessel diameter was 2.86 +/- 0.49 mm, mean lesion length 8.9 +/- 4.3 mm, and prevalence of diabetes mellitus in patients was 13%. The primary end point, the 6-month binary angiographic restenosis rate, was 31.4% for CB and 30.4% for PTCA (p = 0.75). Acute procedural success, defined as the attainment of <50% diameter stenosis without in-hospital major adverse cardiac events, was 92.9% for CB and 94.7% for PTCA (p = 0.24). Freedom from target vessel revascularization was slightly higher in the CB arm (88.5% vs 84.6%, log-rank p = 0.04). Five coronary perforations occurred in the CB arm only (0.8% vs 0%, p = 0.03). At 270 days, rates of myocardial infarction, death, and total major adverse cardiac events for CB and PTCA were 4.7% versus 2.4% (p = 0.03), 1.3% versus 0.3% (p = 0.06), and 13.6% versus 15.1% (p = 0.34), respectively. In summary, the proposed mechanism of controlled dilatation did not reduce the rate of angiographic restenosis for the CB compared with conventional balloon angioplasty. CB angioplasty should be reserved for difficult lesions in which controlled dilatation is believed to provide a better acute result compared with balloon angioplasty alone.     

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.     

N-acetyl-cysteine in the prevention of vascular restenosis after percutaneous balloon angioplasty

BACKGROUND: Vascular inflammation generating oxidized metabolites at the site of balloon angioplasty is believed to play a major role in the process of vessel restenosis. Glutathione, the most potent endogenous antioxidant, may have protective effects after angioplasty by suppressing local inflammatory response. The aim of the study was to test the hypothesis that oral administration of N-acetyl-cysteine (NAC, a precursor of glutathione) reduces restenosis in an animal model of vascular injury. METHODS: In New Zealand white rabbits, an atherosclerotic lesion was introduced to both iliac arteries by air denudation of the endothelium while feeding the animals a high-cholesterol diet. After 4 weeks, all animals underwent balloon angioplasty of the endothelial injury site and half of the group was started on 150 mg/kg NAC per day. Quantitative angiography was performed prior to the angioplasty and at the final procedure 3 weeks later. Glutathione levels were determined in all animals at the beginning and the end of the study. RESULTS: Although not statistically significant, plasma glutathione level increased in the NAC group from 32.4+/-4.4 to 39.7+/-11.6 micromol/l, while it decreased from 30.6+/-13.4 to 28.3+/-11.5 micromol/l in the control group. During the study period, 6 vessels occluded leaving 14 vessels for analysis. Quantitative angiographic analyses prior to angioplasty and at follow-up showed no significant difference with respect to stenosis progression between the groups. Measurement of neointima formation by histology showed also no significant difference between the groups (0.175+/-0.040 mm(2) vs. 0.123+/-0.075 mm(2)), neither did intimal macrophage count as a marker for local inflammatory response. CONCLUSIONS: Despite an increase in plasma glutathione level in the NAC-treated group, there was no reduction in lesion progression after balloon angioplasty. Therefore, NAC does not seem to prevent restenosis after vascular intervention in this animal model.     

Cutting balloon versus conventional balloon angioplasty for the treatment of in-stent restenosis: results of the restenosis cutting balloon evaluation trial (RESCUT)

OBJECTIVES: The aim of this trial was to compare cutting balloon angioplasty (CBA) with conventional balloon angioplasty (i.e., percutaneous transluminal coronary angioplasty [PTCA]) for the treatment of patients with coronary in-stent restenosis (ISR). BACKGROUND: Retrospective studies suggest CBA might be superior to conventional PTCA in the treatment of ISR. METHODS: The Restenosis Cutting Balloon Evaluation Trial (RESCUT) is a multicenter, randomized, prospective European trial including 428 patients with all types of ISR (e.g., focal, multifocal, diffuse, proliferative). RESULTS: In both groups, the majority of ISR lesions were shorter than 20 mm. The length of restenotic stents was similar (CBA: 18.6 +/- 9.7 mm; PTCA: 18.3 +/- 8.7 mm). The number of balloons used to treat ISR was lower in the CBA group: only one balloon was used in 82.3% of CBA cases, compared with 75% of PTCA procedures (p = 0.03). Balloon slippage was less frequent in the CBA group (CBA 6.5%, PTCA 25%; p < 0.01). There was a trend toward a lower need for additional stenting in the CBA group (CBA 3.9%, PTCA 8.0%; p = 0.07). At seven-month angiographic follow-up, the binary restenosis rate was not different between the groups (CBA 29.8%, PTCA 31.4%; p = 0.82), with a similar pattern of recurrent restenosis. Clinical events at seven months were also similar. CONCLUSIONS: Cutting balloon angioplasty did not reduce recurrent ISR and major adverse cardiac events, as compared with conventional PTCA. However, CBA was associated with some procedural advantages, such as use of fewer balloons, less requirement for additional stenting, and a lower incidence of balloon slippage.     

经皮腔内β-射线放射疗法联合切割球囊成形术治疗冠状动脉支架内再狭窄

目的旨在研究经皮冠状动脉(冠脉)内β-射线放射疗法(β-放疗,Novoste)与切割球囊成形术(CBA)联合治疗支架内再狭窄(ISR)的疗效及其安全性.方法冠脉内支架植入术后ISR＞70%的病人295例(男性188例,女性90例,年龄59.76±10.83岁),其中112例均行CBA联合β-放疗为β-放疗组(n=112),183例单独采用CBA(89例)或普通球囊扩张成形术(94例)为对照组(n=183).弥漫性长病变ISR者β-放疗先照射病变远段,再回撤导管照射病变近段.所有病例术前、术后即刻及术后随访期行定量冠脉造影(QCA),分析病变长度,最小管腔直径(MLD),参照管腔直径(RLD)和管腔直径狭窄百分比(DS).防访靶血管再次成形率(TVR)和主要不良心血管事件(MACE)发生率.结果术前及术后即刻两组病人的QCA结果无显著性差异,P＜0.05.随访期(6.3±1.6月)β-放疗组的MLD大于对照组,Ds小于对照组,P＜0.015.β-放疗组与对照组的心绞痛、心肌梗死及死亡率相似(心绞痛为10%对17%,心肌梗死为1%对2%,死亡率为0%对2%,P=NS),但β-放疗组的TVR和MACE明显低于对照组(TVR为5%对16%,MACE为10%对25%,P＜0.05).β-放疗组28例(26%)弥漫性长病变ISR,回撤β-放疗导管分段照射后,随访TVR和MACE无增加.结论冠脉内β-放疗和CBA相结合治疗ISR安全、有效,TVR和MACE明显降低.采用回撤β-放疗导管技术可以有效地治疗弥漫性长病变ISR.