Repeat intracoronary radiation for recurrent in-stent restenosis in patients who failed intracoronary radiation

Extreme coronary radiation doses from intravascular brachytherapy

PURPOSE

To evaluate coronary artery integrity after very high radiation doses from intravascular brachytherapy (IVBT) in the setting of source asymmetry.

METHODS

Ten patients treated for right coronary artery (RCA) in-stent restenosis (ISR) between 2017 and 2021 and for whom follow-up angiograms were available were identified from departmental records. Procedural angiograms, taken to document source position, were used to estimate vascular wall doses. The 2.5 mm proximal source marker was used to estimate the distance from source center to the media and adventitia. Distances were converted to dose (Gy) using the manufacturers' dose fall-off table, measured in water. Follow-up films were scrutinized for any sign of late vascular damage.

RESULTS

The average minimal distance from catheter center to the adjacent media and the adventitia was 0.9 mm (±0.2) mm and 1.4 mm (±0.2), respectively. The average maximum media and adventitial doses adjacent to the source were 75 Gy (±26) and 39 Gy (±14), respectively. Follow-up angiograms were available from 0.6 years to 3.9 years following IVBT (median: 1.6 years). No IVBT-treated vascular segment showed signs of degeneration, dissection or aneurysm.

CONCLUSION

IVBT vascular wall doses are frequently far higher than prescribed. The lack of complications in this unselected group of patients gives a modicum of reassurance that raising the prescription dose is unlikely to lead to a sudden appearance of complications.

The contemporary use of intracoronary brachytherapy for instent restenosis: A review

In-stent restenosis (ISR) has been a major limitation in interventional cardiology and constitutes nearly 10 % of all percutaneous coronary interventions in the United States. Drug-eluting stent (DES) restenosis proves particularly difficult to manage and poses a high risk of recurrence and repeat intervention. Intra-coronary brachytherapy (IBT) has been traditionally viewed as a potential treatment modality for ISR. However, its use was hindered by procedural complexity, cost, and the advent of newer-generation DES. Recent data suggests promising results regarding IBT for the treatment of resistant DES-ISR. This review addresses the mechanism of action of IBT, procedural details, and associated risks and complications of its use. It will also highlight the available clinical evidence supporting the use of IBT and the future directions of its utilization in the treatment of ISR.

Conundrums of coronary brachytherapy

PURPOSE

In the 1998-2005 heyday of intravascular coronary brachytherapy, a variety of delivery devices were developed and marketed. As the industry shrank, only one device, the Novoste Beta-Cath 3.5F System (Best Vascular, Norcross, GA) remained in commercial production. The 2008 instruction manual, the only official source of technical guidance, lacks recommendations for various common scenarios.

METHODS AND MATERIALS

The clinical conundrums described here were encountered during regular use of the Novoste system in 81 patients treated from January to December of 2020 in the course of using the Novoste device in accordance with the 2008 manufacturer's instruction manual. Our experience and strategies are reported and critiqued.

RESULTS

Ambiguous patient selection factors include vein grafts, multiple affected vessels, large vessels, retreatment, multiple overlapping stents and prior radiation. Procedural ambiguities include vessel size determination, proper prescription dose, very long lesions and eccentric source positioning. Potential procedural mishaps include stuck sources and the risk of contamination.

CONCLUSIONS

The Novoste intravascular coronary brachytherapy system is the only commercially available brachytherapy delivery catheter, and may remain so for some time. The issues detailed here provide insight and guidance for current users and may prompt research into areas lacking adequate information.

Is Coronary Brachytherapy Staging a Comeback for the Treatment of In-Stent Restenosis?

PURPOSE OF REVIEW

The catheter-based coronary intervention has become a well-established therapeutic modality for obstructive coronary artery disease. However, in-stent restenosis remains a significant limitation of coronary intervention despite the use of newer devices. Intravascular brachytherapy was introduced to treat recurrent in-stent restenosis but only modestly adopted. This review will discuss the mechanism of intracoronary brachytherapy, available clinical evidence of brachytherapy in recurrent in-stent restenosis treatment, and the future of coronary brachytherapy in coronary intervention.

RECENT FINDINGS

Drug-eluting stents have an inherent limitation as they leave a permanent metal layer inside an artery when deployed. Recently, drug-coated balloon technology has emerged to treat coronary artery disease as a combination of balloon angioplasty and local drug delivery without leaving a metal layer behind. Recent European guidelines recommended using drug-coated balloons when treating in-stent restenosis treatment, while the US guidelines have not yet addressed the use of drug-coated balloons in such cases. Coronary brachytherapy is a valuable addition to treat these challenging diseases despite several logistic issues. If there are newer technologies with easier setup, such as drug-coated balloons, coronary brachytherapy resurgence is improbable in the contemporary era, although it may not become obsolete.

Intravascular coronary brachytherapy combined with a drug-coated balloon

BACKGROUND

Coronary artery disease leads to stenosis of the major cardiac vessels, resulting in ischemia and infarction. Percutaneous intervention (PCI) with balloon angioplasty can re-open stenosed vessels. Drug eluting stents (DES) and intravascular brachytherapy (IVBT) and drug-coated balloons (DCBs) are proven to decrease the likelihood of another restenosis after PCI, but neither is completely effective. Due to the limited long-term effectiveness of IVBT or DCB used separately for salvage PCI, we combined the two in some poor prognosis patients.

METHODS

Combined IVBT+DCB was intended for a total of 36 patients from 2015-2020. PCI with some combination of ballooning, laser and directional/rotational atherectomy was used to maximally open the stenotic region prior to IVBT+DCB. Beta-radiation brachytherapy for all patients was done with a Novoste Beta-Cath. Lutonix 4.0 x 40 mm paclitaxel-coated balloons (Bard, Murray Hill, NJ) were employed.

RESULTS

Overall survival at two years was 88%. Nine patients had follow-up angiograms, all for cardiac symptoms. Time from IVBT+DCB to follow-up angiography ranged from 4 to 33 months. The average months PCI-free interval before brachy therapy was 11.1 mos (95% CI 1.03-23.25) versus 23.3 mos after VBT (23.3 95% CI 12.3-32.3). The mean difference was 11.2 mos (95% CI 1.06-21.4, p < 0.031). None of the follow-up angiographic procedures displayed evidence of what could be interpreted as radiation damage.

CONCLUSIONS

In this uncontrolled series, IVBT plus DCB appeared to lengthen the ISR-free interval relative to what had been achieved prior to the combined intervention. We view these results as mildly encouraging, worthy of further study.

Treatment of Patients With Recurrent Coronary In-stent Restenosis With Failed Intravascular Brachytherapy

Intravascular brachytherapy (VBT) is an effective and safe treatment option for recurrent drug-eluting stent (DES) in-stent restenosis (ISR). However, the optimal therapy for patients with failed VBT is not well-defined. In this study, we sought to evaluate the optimal treatment strategy for patients after a failed VBT. Patients with recurrent ISR after an initial unsuccessful VBT were identified from our percutaneous coronary intervention database. Patients were divided into 2 cohorts (standard treatment with DES or balloon angioplasty versus repeat VBT). Baseline characteristics and clinical outcomes during follow-up were extracted. A total of 279 patients underwent PCI after an initial unsuccessful VBT at our institution. Of those, 215 (77%) patients underwent standard treatment with balloon angioplasty with or without DES, and 64 (33%) underwent balloon angioplasty followed by repeat VBT. The mean age of the cohort was 64±11 years. Overall, 71% were men, 47% had diabetes, and 22% had heart failure. The majority (64%) presented with unstable angina. The groups had similar baseline characteristics. The rate of major adverse cardiovascular events (defined as all-cause mortality, myocardial infarction, or target vessel revascularization) was significantly lower in the repeat VBT group at 1 year (31% vs 14%, p = 0.03), 2 years (51% vs 31%, p = 0.03), and 3 years (57% vs 41%, p = 0.08). Target lesion revascularization and target vessel revascularization were consistently lower in the repeat VBT group at all follow-up intervals than in the standard treatment group. Treatment of recalcitrant ISR following an initial failed VBT is associated with a high MACE rate at 3-year follow-up. Repeat VBT is safe and effective and should be considered as the preferred strategy.

Coronary stenting with the sirolimus-eluting stent in patients with restenosis after intracoronary brachytherapy: results from the prospective multicentre German Cypher Stent Registry

BACKGROUND

Treatment of restenosis following intracoronary brachytherapy (ICB) is still a challenging problem. Implantation of sirolimus-eluting stents (SES) in this setting may be an option to be evaluated.

METHODS AND RESULTS

We analysed the prospective multicentre SES registry, the German Cypher Stent Registry. 7,445 patients treated with an SES during percutaneous coronary intervention (PCI) were registered. Out of these patients, 61 (0.8%) were treated for restenosis after ICB: 56 patients with completed follow-up could be evaluated. Median age was 65 years, with 80% male patients. 48% of patients had a prior myocardial infarction and 25% had already coronary bypass surgery (CABG). Type B2 lesion was present in 40% and type C lesion in 22.4%. Event rates from SES implantation until 6.6 months follow-up were death 0%, myocardial infarction 3.6%, stroke 2.1%. Target vessel revascularization rate (TVR) was 16.4%, and major adverse cardiovascular or cerebral events (MACCE) or TVR occurred in 17.9% of patients. This TVR rate was higher compared with that of other patients treated with an SES: 8.4% (P = 0.04). During 65 months follow-up MACCE or TVR occurred in 44.6% of patients.

CONCLUSIONS

The treatment of lesions after ICB occurred in 0.8% out of all patients treated with an SES. Clinical event rates during early follow-up were low. However, the TVR rate was 16.4%, which was significantly higher when compared with other SES-treated patients (8.4%, P = 0.04). The treatment of restenosis after ICB with SES seems to be safe and reasonably effective; however, there might be a late catch-up phenomenon.

Intracoronary β‐irradiation enhances balloon‐injury‐induced tissue factor expression in the porcine injury model

Intracoronary brachytherapy (ICBT) effectively reduces restenosis but is associated with late thrombosis. Since tissue factor (TF) is an important mediator of arterial thrombosis, we tested the hypothesis that ICBT results in persistently augmented TF expression. Coronary arteries from 12 pigs were randomized to: control (C; no injury), oversized balloon injury (BI), or BI followed by ICBT. Animals were sacrificed at 1, 7, 14, or 60 days postprocedure, and coronary arteries collected for expression analyses and immunostaining. ICBT-treated arteries had higher TF antigen and activity at all time-points compared to BI arteries (Western blot: 16 571 +/- 2090 vs 10 135 +/- 2939 densitometric units, p = 0.001; ELISA: 0.42 +/- 0.13 nM vs 0.25 +/- 0.14 nM, p = 0.001; TF activity assay: 0.303 +/- 0.11 nM vs 0.18 +/- 0.07 nM, p = 0.01; immunohistochemical staining: 30.6 +/- 6.6% vs 11.5% +/- 3.2%, p = 0.01). TF expression increased following BI, increased further following ICBT, and persisted for the duration of the study. We conclude that TF expression increases after BI, but is further increased and persists for a longer duration following ICBT, suggesting that a TF-mediated mechanism may play a role in late thrombosis following ICBT.

Feasibility and safety of intra-coronary Beta irradiation with 144Ce/Pr for prevention of restenosis after percutaneous transluminal coronary angioplasty of in-stent restenotic lesions

BACKGROUND

Endovascular brachytherapy is a proven and efficacious treatment of coronary in-stent restenosis with established long-term benefit. Owing to its complexity and logistic inconveniences, brachytherapy did not find wide acceptance, especially in the current drug-eluting stents era. We conducted a single center, non-randomized pilot trial with 144Ce/Pr, utilizing a new high-energy Beta emitting source, for prevention of restenosis after percutaneous treatment of in-stent restenotic lesions.

METHODS AND RESULTS

Thirty consecutive patients presenting in-stent restenosis were enrolled in the study. After conventional balloon angioplasty, 144Ce/Pr was applied to the dilated coronary segment at a dose of 21Gy. Technical feasibility, safety and efficacy of 144Ce/Pr at 9 months clinical and angiographic follow-up were tested. Thirty-seven arterial segments were irradiated with 100% technical success and no in-hospital major adverse cardiac events (MACE). Five MACE were observed (13.5% of the treated segments) during 9 months follow-up, including four target lesion revascularizations and one episode of acute coronary syndrome secondary to sudden late thrombotic occlusion of the irradiated segment.

CONCLUSIONS

The study confirmed the safety and the feasibility of the intra-coronary Beta irradiation utilizing the 144Ce/Pr source. It also shows some practical advantages compared to traditional Gamma or other Beta sources. Considering the high-risk restenosis profile of the selected patients (i.e. diffuse in-stent restenosis, bifurcation lesions, small vessels) these results are encouraging in terms of restenosis prevention. Late acute thrombosis remains a problem requiring further improvement.

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.

IVUS-based dosimetry on patients with repeat-radiated coronary arteries to the same site

BACKGROUND AND PURPOSE

Intracoronary radiation reduces recurrent in-stent restenosis (ISR). Repeat radiation may become necessary due to recurrent ISR. This study reports outcome-related dose calculations for twice-radiated coronary artery segments.

MATERIALS AND METHODS

A total of 22 patients with angiographic evidence of ISR in a previously treated native coronary artery were assigned for repeat percutaneous coronary intervention and intravascular brachytherapy (IVBT). Intravascular brachytherapy was performed either with a 192Ir- or a 90Sr/Y-source (prescription dose: 14-18 and 23 Gy each at 2 mm from the center of the source), or a 32P-source (20 Gy 1-mm deep to the vessel wall). The mean time interval between the two IVBT treatments was 394+/-306 days. For each patient, angiograms and intravascular ultrasound cross sections were reviewed, on the basis of anatomical landmarks, matched, and the twice-radiated vessel segment identified.

RESULTS

Clinical follow-up at 379+/-146 days revealed a target vessel revascularization rate of 18.2% and a target lesion revascularization rate of 13.6%. One death was reported. Maximal dose and average dose at the endothelium were 261 and 124+/-72.3 Gy, and maximal dose and average dose at the adventitia-media border were 159 and 50.3+/-29.3 Gy. Fourteen patients had 1.71 times longer recurrence-free interval compared to the interval between both IVBT treatments.

CONCLUSIONS

Repeat IVBT to the same ISR site is safe without any adverse clinical events at an average 12 months' follow-up. A second IVBT treatment led to a prolonged ISR-free survival for the majority of patients. The choice of isotope did not influence outcome.

Three-year follow-up after intracoronary beta-radiation therapy for in-stent restenosis

BACKGROUND

Most studies that proved intracoronary radiation therapy (IRT) to be highly effective to reduce recurrent restenosis after treatment of in-stent restenosis (ISR) have looked at time periods up to 12 months. Whether the beneficial effect from radiation is sustained during long-term follow-up remains a concern. This study sought to evaluate the effectiveness of IRT using a beta-emitter during a 3-year follow-up period.

METHODS

One hundred twenty-eight consecutive symptomatic patients (mean age, 63 +/- 11 years) with 134 in-stent restenotic lesions were treated for ISR with IRT (noncentred beta-emitter, Novoste; radiation dosis 21.1 +/- 3.1 Gy). Six-month angiographic follow-up was obtained in 104 patients (81%) with 105 lesions (78%). All patients underwent 36-month clinical follow-up.

RESULTS

Six-month angiographic restenosis rate was 22% in stent (29% in lesion) with an in-stent late loss of 0.49 +/- 0.62 mm. Target lesion resvascularization (TLR) at 6-month follow-up was performed in 23 cases (18%). MACE (death, myocardial infarction, and target vessel revascularisation) was observed in 24 patients (19%). At 36-month follow-up, TLR increased to 36 cases (28%) and MACE was observed in 47 patients (37%). In a multivariate analysis, minimal lumen diameter before treatment of ISR using IRT was the only predictor of recurrent TLR at 36 months (OR = 0.131; 95% CI, 0.068-0.254; p = 0.002). In a subgroup of patients (N = 15) without restenosis at 6-month angiography but with clinically driven recurrent late angiography (mean, 18 +/- 7 months); in-lesion late loss increased from 0.47 +/- 0.54 mm at 6 months to 1.27 +/- 0.76 mm at repeated angiography (p = 0.005).

CONCLUSION

There is a considerable number of delayed recurrent restenosis post IRT for ISR. This is due to ongoing late loss more than 6-month post IRT. The minimal lumen diameter before IRT predicts the need for recurrent TLR at 36 months.

Brachytherapy for restenosis after stenting for coronary artery disease: its role in the drug-eluting stent era

PURPOSE OF REVIEW

Recent years have brought remarkable changes to the field of interventional cardiology. The need for repeat intervention due to restenosis, the most vexing long-term failure of percutaneous coronary intervention, has been significantly reduced owing to the introduction of two major advances, the vascular brachytherapy (VBT) and the drug-eluting stents (DES).

RECENT FINDINGS

Vascular brachytherapy has demonstrated its efficacy in limiting recurrence of existing in-stent restenosis. The past 2 years have sealed its reputation, with a variety of studies demonstrating its superiority over conventional therapy in challenging patient subsets with high risk for restenosis recurrence. Moreover, the long-term follow-up confirmed durability of this therapy, and the failures of VBT were characterized as easy to treat. Conversely, DES have shown spectacular efficacy at primarily preventing the first restenosis episode following the initial stent placement. Consequently, the role of VBT may be minimized, as the overall need for repeat revascularization is diminished as a result of the wide acceptance of DES. Furthermore, if the capacity of DES to treat in-stent restenosis is confirmed in randomized trials, they may eventually supersede VBT as the therapy of choice for in-stent restenosis.

SUMMARY

At present, VBT is the proven and durable therapeutic choice for patients with complex, diffuse in-stent restenosis who would otherwise have a very poor prognosis for long-term event-free survival. DES have emerged as remarkably effective in minimizing the first restenosis occurrence; they also represent a promising and competitive alternative to VBT for the treatment of in-stent restenosis.

Intracoronary Brachytherapy for Treatment of In-Stent Restenosis

Randomized, double-blind, placebo-controlled trials have demonstrated that intracoronary brachytherapy is more efficacious than placebo in reducing death, myocardial infarction, and target vessel revascularization at long-term follow up of patients with in-stent restenosis. Intracoronary brachytherapy is efficacious in treating totally occluded in-stent restenotic lesions, in treating de novo and in-stent restenotic lesions in saphenous vein grafts, in treating diffuse in-stent restenosis, in treating native coronary ostial in-stent restenotic lesions, in treating patients with diabetes with in-stent restenosis, in treating patients at high-risk for recurrence of restenosis, in treating elderly patients, and in treating patients who failed intracoronary radiation. Beta and gamma intracoronary brachytherapy are equally effective in treating in-stent restenosis. Long-term aspirin and clopidogrel should be administered for at least 1 year to reduce late vessel thrombosis. Inadequate radiation may cause edge stenosis.

Superiority of sirolimus eluting stent compared with intracoronary beta radiation for treatment of in-stent restenosis: a matched comparison

OBJECTIVE

To compare acute and follow up clinical and angiographic results after treatment of in-stent restenosis (ISR) by sirolimus eluting stents (SES) with results obtained after intracoronary radiation therapy (IRT).

DESIGN

Matched pair analysis.

METHODS

62 consecutive ISR lesions (< 30 mm lesion length, reference diameter < 3.5 mm) in 62 patients were treated with SES. From a database of 174 lesions (n = 141 patients) treated for ISR by intracoronary beta radiation, 62 lesions (62 patients) were pair matched with the SES group for diabetes mellitus, lesion length, vessel size, and pattern of ISR. Six month angiographic and 12 month clinical follow up results were obtained.

RESULTS

Baseline clinical and angiographic characteristics were similar between the groups (not significant). SES implantation resulted in significantly lower postprocedural in-lesion diameter stenosis than did IRT (mean (SD) 14.2 (9.5)% v 21.1 (10.6)%, p = 0.001), significantly higher minimum lumen diameter at follow up (1.91 (0.58) v 1.55 (0.72) mm, p = 0.005), and a higher net gain (1.16 (0.55) v 0.77 (0.70) mm, p = 0.002). Angiographic binary in-lesion restenosis rate at six months was 11% in the SES group and 29% in the IRT group (p = 0.046). In 16 ISR lesions SES were used after failed IRT and in 46 lesions for first time ISR. In-lesion late loss was higher after use of SES for failed IRT than after use of SES for first time ISR (0.61 (0.67) mm v 0.24 (0.41) mm, p = 0.018). In a multivariate analysis prior failed IRT was the only independent predictor for recurrent restenosis after SES for ISR (p = 0.052, odds ratio 5.8). Six patients (10%) in the SES group and 17 patients (27%) in the IRT group underwent target lesion revascularisation during the 12 months of follow up (p = 0.022).

CONCLUSIONS

In this non-randomised matched cohort SES achieved acute and follow up results superior to IRT for treatment of ISR even if cases of failed IRT are included. Failed IRT is a predictor of impaired SES effectiveness.

Drug-eluting stents for the treatment of in-stent restenosis

Treatment of in-stent restenosis (ISR) remains problematic despite the widespread application of drug-eluting stents (DES). Challenging lesion cohorts such as diffuse ISR and restenosis after failed intracoronary radiation therapy (IRT) maybe best treated with DES. The overall benefit of DES appears inferior to their utility in treating de novo coronary lesions. Randomised trials comparing DES and IRT will soon be available to determine the optimal therapy for ISR. The challenge to treat ISR in the DES era is the next frontier of interventional cardiology.

Angiographic and clinical outcomes of late total occlusion versus treatment failure without late total occlusion in patients after intracoronary radiation therapy for in-stent restenosis

This study aimed to compare the outcomes of patients with late total occlusion (LTO) versus patients with recurrence in the absence of LTO after intracoronary radiation therapy for in-stent restenosis. LTO, especially in the context of acute myocardial infarction, after intracoronary radiation therapy for in-stent restenosis, is associated with negative clinical outcomes after 6 and 12 months compared with in-stent restenosis without LTO.

Two-year outcomes of repeated brachytherapy in patients with restenosis after intracoronary radiation therapy

This study compared the 2-year outcomes of repeat brachytherapy (n = 10) and conventional percutaneous intervention (n = 14) in patients with restenosis after intracoronary brachytherapy with a rhenium-188-filled balloon system. The short-term target lesion revascularization rate was significantly lower in the repeat brachytherapy group (0% vs 36%, p = 0.038), and additional target lesion revascularization was required in 2 patients with repeat brachytherapy during 2-year follow-up. There were no vascular complications related to repeat brachytherapy.

Comparison of acute and long-term results and underlying mechanisms from sirolimus-eluting stent implantation for the treatment of in-stent restenosis and recurrent in-stent restenosis in patients in whom intracoronary radiation failed as assessed by intravascular ultrasound

In-stent restenosis (ISR), especially after vascular brachytherapy, is a therapeutic challenge. Sirolimus-eluting stent implantation is a promising new option for the treatment of patients with ISR. The efficacy of sirolimus-eluting stent implantation for the treatment of patients with their first episodes of ISR and with recurrent ISR due to the failure of vascular brachytherapy was compared using intravascular ultrasound imaging.

Effectiveness of sirolimus-eluting stent implantation for treatment of in-stent restenosis after brachytherapy failure

The impact of the use of sirolimus-eluting stents (SESs) in the treatment of in-stent restenosis in previously irradiated sites has not been adequately evaluated. Fifteen consecutive patients who underwent percutaneous coronary interventions using SESs in lesion sites previously intervened with intracoronary radiation therapy were identified. All stents were implanted successfully, and there were no major in-hospital complications. At 30-day follow-up, there was 1 case of subacute thrombosis that led to target lesion revascularization (TLR). At 6 months, 2 patients underwent TLR because of recurrent angina with angiographic restenosis, and 1 patient underwent target vessel revascularization distally to the SES site; no other major adverse cardiac events occurred at long-term follow-up (mean 17 +/- 8 months).