Diffuse In-stent Restenosis Research Articles

Predictors for Functionally Significant In-Stent Restenosis: An Integrated Analysis Using Coronary Angiography, IVUS, and Myocardial Perfusion Imaging

The aim of this study was to assess the clinical and morphological predictors for functionally significant in-stent restenosis (ISR).Although they have been studied de novo in native coronary artery lesions, the relationships between clinical and morphological characteristics and the hemodynamic significance of ISR are not well understood.In 175 patients with ISR of a single coronary artery (angiographic stenosis >50%), we compared quantitative coronary angiography and intravascular ultrasound (IVUS) with stress myocardial single-photon emission computed tomography (SPECT). A positive SPECT was a reversible perfusion defect in the territory of the ISR artery.Overall, 103 (59%) patients had a positive SPECT. In-segment IVUS minimal lumen area (MLA) was significantly smaller in lesions with positive SPECT compared with negative SPECT (1.7 ± 0.5 mm(2) vs. 2.4 ± 0.8 mm(2), p < 0.001). Stent underexpansion (minimal stent area <5.0 mm(2)) was more common in the positive SPECT group than in the negative SPECT group (52% vs. 32%, p = 0.010). A positive SPECT was seen in 54% (65 of 121) of focal ISR lesions compared with 70% (38 of 54) of multifocal or diffuse ISR lesions as assessed by IVUS (p = 0.039). Independent determinants for a positive SPECT were diabetes (odds ratio [OR]: 2.41; 95% confidence interval [CI]: 1.02 to 5.68; p = 0.046), in-segment angiographic diameter stenosis (OR: 1.06; 95% CI: 1.03 to 1.09; p < 0.001), in-segment IVUS-MLA (OR: 0.30; 95% CI: 0.14 to 0.63; p = 0.001), stent underexpansion (minimal stent area <5.0 mm(2)), (OR: 2.91; 95% CI: 1.19 to 7.07; p = 0.019), proximal location of the IVUS-MLA (OR: 4.62; 95% CI: 1.75 to 12.18; p = 0.002), and a multifocal or diffuse ISR pattern (OR: 2.50; 95% CI: 0.99 to 6.28; p = 0.050). An in-segment angiographic diameter stenosis ≥69.5% (72% sensitivity, 74% specificity, area under the curve = 0.793) and an IVUS-MLA ≤1.9 mm(2) (67% sensitivity, 75% specificity, area under the curve = 0.756) best predicted a positive SPECT; however, the overall diagnostic accuracies were only 73% and 70%, respectively.In lesions with ISR, neither angiography nor IVUS accurately predicted an abnormal SPECT.

Comparison of efficacy and safety between sirolimus, paclitaxel, everolimus-eluting stent and drug-eluting balloon on the outcome of patients with diffuse in-stent restenosis after BMS implantation

Purpose: The aim of this study is to compare the safety and efficacy of Sirolimus (SES), Paclitaxel (PES), Everolimus-eluting stent (EES) and SeQuent™ Please, a drug-eluting balloon (DEB) on the outcome of patients with diffuse in-stent restenosis (D-ISR) after bare metal stent (BMS) implantation. Methods: A prospective analysis of 1078 patients with 1251 D-ISR lesions (427 SES, 363 PES, 232 EES and 229 DEB) in six high volume Asian centers after successful stent implantation (SES: LAD 45.7%, LCX 27.9%, RCA 26.4%) (PES: LAD 46.0%, LCX 22.9%, RCA 31.1%) (EES: LAD 50.0%, LCX 21.0%, RCA 29.0%) (DEB: LAD 54.0%, LCX 23.0%, RCA 23.0%) was performed. The study endpoints were major adverse cardiac events (MACE) and target lesion revascularization (TLR) at 12 and 24 months. Results: See table for clinical results. View this table: Conclusion: (1) The use of SES, PES, EES and DEB in patients with D-ISR seems to be favorable in terms of in-hospital clinical outcome. (2) Patients treated with DEB showed higher restenosis rate and TLR compared with DES.

Invited commentary

The strengths of this multicenter prospective trial comparing bare nitinol stents to polytetrafluoroethylene stent grafts for TransAtlantic Inter-Society Consensus 1 C and D superficial femoral artery lesions include an uncommon effort to standardize methodology and an uncommon glimpse at 3-year outcomes. The investigators are to be commended for attempting to drive a guidepost into the riverbed and refusing to go with the flow, simply assuming that any decent study will be outdated by intercurrent innovations such as drug-eluting stents and heparin-bonded stent grafts. The study tests the reasonable hypothesis that covered stents would eliminate in-stent restenosis, a chief cause of nitinol stent failure. Though the patency comparisons at 3 years suffer from some attrition of patients with cautionary wobble in the Kaplan-Meier curves, there was no apparent patency advantage to stent grafts. The reader remains intrigued by the lack of details regarding the ultrasound and angiographic lesions responsible for device failure, which given the surveillance protocol and high rate of reintervention, must have been available to allow distinction between intimal hyperplasia at the stent margins or within the stents and progression of disease in untreated adjacent arterial segments. Among patients followed for 36 months, the stent fracture rate was 50% for nitinol stents and only 2% for stent grafts. Acknowledging that the impact of stent fracture is controversial, if one assumes a negative impact of fracture on nitinol stent patency and a positive impact of less in-stent restenosis on stent graft patency, we might have expected an unequivocal patency advantage for stent grafts rather than the somewhat disappointing equivalency between the two groups. If indeed nitinol stents and stent grafts do have similar efficacy, device cost would assume more importance in the current penny-pinching era. Comparison of trial results with surgical bypass is invalidated by randomization of patients only after lesions had been crossed by a guidewire. Nonetheless, optimal results at 3 years were attained only after one or more reinterventions in 40% of patients, a much higher rate than might be expected in a series of superficial femoral artery bypasses. Again, costs need consideration. The study employed somewhat confusing patency definitions unfamiliar to most surgeons accustomed to tracking bypass grafts. Development of standards for reporting has been one of the signal contributions to vascular surgery over the years, and we must extend this effort to the endovascular arena, including our colleagues in related subspecialties. Only by adopting uniform research methodology can we build fruitfully on earnest efforts such as those of the VIBRANT trial team. Three-year results of the VIBRANT trial of VIABAHN endoprosthesis versus bare nitinol stent implantation for complex superficial femoral artery occlusive diseaseJournal of Vascular SurgeryVol. 58Issue 2PreviewThe predominant mode of bare nitinol stent failure is diffuse in-stent restenosis, and failure rates correlate to the length and complexity of the treated lesion. Addition of an expanded polytetrafluoroethylene lining to a nitinol stent frame, as found in the VIABAHN endoprosthesis, mitigates the ingrowth of intimal hyperplasia. We compared the long-term outcomes of complex superficial femoral artery disease intervention using the VIABAHN endoprosthesis to those obtained with bare nitinol stent implantation. Full-Text PDF Open Archive

Mid‐term outcomes following endovascular re‐intervention for iliac artery in‐stent restenosis

We sought to evaluate the procedural characteristics and clinical outcomes of endovascular repair for iliac artery (IA) in-stent restenosis (ISR). An increasing percentage of patients with complex IA occlusive disease are treated with an endovascular approach, but the outcomes of IA-ISR have not been well described. We analyzed all endovascular procedures for treatment of IA-ISR performed at our institution between July 2006-December 2010. The primary outcome was primary patency, defined as <50% stenosis as assessed by clinical examination and duplex ultrasonography (DUS). Forty-one lesions in 24 patients who underwent repeated endovascular intervention for treatment of IA-ISR. Most lesions were unilateral and involved the common IA (66%). The mean length of ISR was 30.1 ± 14.1 mm with type I (focal) and II (diffuse) ISR occurring with the greatest frequency (34% and 39%, respectively). All patients underwent balloon angioplasty; adjunctive stenting zwas performed in 27 (66%) of the lesions. Type II ISR lesions more frequently required stenting (13/16 lesions, P = 0.02 compared with other patterns of ISR). Procedural success was 100% with a mean gain of 0.13 in the ankle-brachial index (P = 0.001). The 6- and 12-month primary patency rates were 96% and 82%, respectively. The 12-month primary-assisted patency rate was 90% with clinically driven target lesion revascularization (TLR) in three patients. Endovascular treatment of IA-ISR using an approach of balloon angioplasty followed by selective stenting is associated with high-patency rates and low rates of TLR at 1 year.

Three-year results of the VIBRANT trial of VIABAHN endoprosthesis versus bare nitinol stent implantation for complex superficial femoral artery occlusive disease

The predominant mode of bare nitinol stent failure is diffuse in-stent restenosis, and failure rates correlate to the length and complexity of the treated lesion. Addition of an expanded polytetrafluoroethylene lining to a nitinol stent frame, as found in the VIABAHN endoprosthesis, mitigates the ingrowth of intimal hyperplasia. We compared the long-term outcomes of complex superficial femoral artery disease intervention using the VIABAHN endoprosthesis to those obtained with bare nitinol stent implantation. One hundred forty-eight patients with symptomatic complex superficial femoral artery disease (TransAtlantic Inter-Society Consensus I class C and D lesions, accompanied by intermittent claudication or ischemic rest pain) were randomized to endovascular intervention using either bare nitinol stent implantation (76 patients) or nonheparin-bonded VIABAHN endoprosthesis deployment (72 patients). Patency, limb hemodynamics, and quality of life were evaluated at 1, 6, 12, 24, and 36 months following intervention. The average treated lesion measured 18 ± 8 cm in length, and 58.8% of lesions displayed segmental or complete occlusion. At 3 years, primary patency rates (defined by peak systolic velocity ratio ≤ 2.0 and no target lesion revascularization) did not significantly differ between patients treated with the VIABAHN stent graft and those who received a bare nitinol stent (24.2% vs 25.9%; P = .392). Stent fractures were significantly more common in bare nitinol stents (50.0%) than in the VIABAHN endoprostheses (2.6%). Primary-assisted patency rates were higher in those receiving bare nitinol stents than the VIABAHN stent graft (88.8% vs 69.8%; P = .04), although secondary patency rates did not differ between bare nitinol stent and stent graft recipients (89.3% vs 79.5%; P = .304). There were no instances of procedure-related mortality or amputation. The hemodynamic improvement and quality measures improved equally in both groups. The long-term outcomes of complex superficial femoral artery disease intervention using the VIABAHN endograft and bare nitinol stents are similar. Although primary patency rates are low in both study arms, excellent primary-assisted and secondary patency rates were achieved, with sustained augmentation of limb perfusion and quality-of-life measures. Patency rates diminish most rapidly in the first year after device implantation.

Secondary revascularization — repeated percutaneous coronary intervention or coronary artery bypass graft?

67-year old female patient with previous history of hypertension, hyperlipoproteinemia and coronary artery disease was admitted to our hospital for recoronarography. 6 months ago she had a PCI procedure on the right coronary artery (RCA) and the ACx. PCI on the RCA was performed successfully with two BM stent. During the procedure on the LCA the guiding catheter made a dissection of the LMCA and the ascending aorta producing a crescent-shaped shadow. The dissection was successfully solved percutaneously, with implantation of multiple BM stents in LAD, avoiding the surgical intervention at that moment. The crescent-shaped shadow in ascending aorta disappeared as well. Systolic function was preserved. She is presenting now with dyspnea and stable angina, and the angio is to be done for reevaluation of the disease. On the recoronarography, the finding was the diffuse in-stent restenosis in LAD with good collaterals from the RCA. The stents implanted in the RCA were good, and the ACx was patent, with a stenosis. An ischemic cardiomiopathy has developed, with EF of 30%. Clinical question was whether there was a viable myocardium in LAD perfusion territory demanding secondary revascularization. In order to find viable myocardium, its amount and localization, the stress MRI was performed. Viability study showed that the biggest amount of viable myocardium was in LAD perfusion territory, making reasonable the secondary revascularization. Two possibilities were confronting — bypass grafting or reintervention with DE stents. The decision was made and successful reintervention with DE stents was performed during hospitalization. Before discharge, stress test was negative (96%), and on the control, three months later, echo showed improved EF LV of 45%, and stress test was negative as well (110%). The necessity for secondary revascularization is our every day problem. There are many issues that have to be taken in consideration when deciding of secondary revascularization. This case showed the proposed strategy for solving some dilemmas and finding the best solution.

TCT-70 Comparison of Efficacy and Safety between Sirolimus, Paclitaxel, Everolimus-Eluting Stent and SeQuent™ Please, a Drug-Eluting Balloon on the Outcome of Patients with Diffuse In-Stent Restenosis after Bare Metal Stent Implantation

Purpose: The aim of this study is to compare the safety and efficacy of Sirolimus (SES), Paclitaxel (PES), Everolimus-eluting stent (EES) and SeQuent™ Please, a drug-eluting balloon (DEB) on the outcome of patients with diffuse in-stent restenosis (D-ISR) after bare metal stent (BMS) implantation. Methods: A prospective analysis of 1078 patients with 1251 D-ISR lesions (427 SES, 363 PES, 232 EES and 229 DEB) in six high volume Asian centers after successful stent implantation (SES: LAD 45.7%, LCX 27.9%, RCA 26.4%) (PES: LAD 46.0%, LCX 22.9%, RCA 31.1%) (EES: LAD 50.0%, LCX 21.0%, RCA 29.0%) (DEB: LAD 54.0%, LCX 23.0%, RCA 23.0%) was performed. The study endpoints were major adverse cardiac events (MACE) and target lesion revascularization (TLR) at 12 and 24 months. Results: See table for clinical results. Conclusion: (1) The use of SES, PES, EES and DEB in patients with D-ISR seems to be favorable in terms of in-hospital clinical outcome. (2) Patients treated with DEB showed higher restenosis rate and TLR compared with DES.

Coronary stent fracture resulting in pseudoaneurysm

A 72-year-old male with past history of type 2 diabetes mellitus and coronary artery bypass grafting presented with progressive angina 6 months following a percutaneous coronary intervention (PCI) for diffuse in-stent restenosis (ISR) of a drug eluting stent (Taxus Liberte) implanted in tortuous left circumflex artery (LCx). The ISR was treated using a paclitaxel-eluting balloon. The CT angiography revealed a fracture of the stent with complete separation of the 2 segments with malalignment and a gap of 5 mm (Fig. 1, panel A, B arrow head). The proximal segment was communicating with a large pseudoaneurysm (Fig. 1, panel A, B arrow). The LCx was totally occluded distal to the communication. Fig. 1 CT coronary angiography: Complete stent fracture with malalignment of two segments and a gap of 5mm, the proximal segment communicating with a large pseudoaneurysm. Panel A: Axial cut. Panel B: 3D reconstructed image. Fracture of the stent was possibly because of shear force on the curve of the LCx artery resulting from cardiac contractions. The paclitaxel induced inflammatory changes in the vessel wall could have contributed in the weakening of the arterial wall resulting in the pseudoaneurysm. The pseudoaneurysm was successfully closed with 3 stainless steel coils (Cook Inc., Bloomington, IN, USA) (MWCE-18-3-3).

Randomized Trial of Optimal Treatment Strategies for In-Stent Restenosis After Drug-Eluting Stent Implantation

The purpose of this study is to compare the efficacy of the treatment strategies for in-stent restenosis (ISR) of drug-eluting stents (DES) according to the morphologic pattern of restenosis. Optimal treatment strategies for ISR within DES have not been adequately addressed yet. Patients with ISR of DES were randomized according to the lesion length to compare outcomes of sirolimus-eluting stent (SES) versus cutting balloon angioplasty for focal type (≤10 mm) and SES versus everolimus-eluting stent (EES) for diffuse type (>10 mm). The primary endpoint was in-segment late loss at 9 months. Overall 162 patients, 96 with focal ISR and 66 with diffuse ISR, were enrolled. In focal lesions, in-segment late loss was significantly higher in the cutting balloon group (n = 48) than in the SES group (n = 48; 0.25 mm, interquartile range [IQR]: -0.01 to 0.68 mm vs. 0.06 mm, IQR: -0.08 to 0.17 mm; p = 0.04). Consequently, in-segment restenosis rate tended to be higher in the cutting balloon group than in the SES group (20.7% vs. 3.1%, p = 0.06) with comparable incidences of the composite of death, myocardial infarction, or target vessel revascularization at 12 months of clinical follow up (6.3% vs. 6.3%, p > 0.99). In 66 cases of diffuse ISR, in-segment late loss (0.11 mm, IQR: -0.02 to 0.30 mm; vs. 0.00 mm, IQR: -0.08 to 0.25 mm; p = 0.64), in-segment restenosis rate (5.0% vs. 14.3%, p = 0.32), and the composite incidence of death, myocardial infarction, or target lesion revascularization (9.6% vs. 8.8%, p > 0.99) did not differ between SES group (n = 32) and EES group (n = 34). For lesions of focal DES restenosis, repeat implantation of SES is more effective in reducing late luminal loss and subsequent restenosis rate than cutting balloon angioplasty. For diffuse DES restenosis, implantation of SES or EES is comparably effective in terms of angiographic and clinical outcomes.

Efficacy of Drug-Eluting Stents for Treating In-Stent Restenosis of Drug-Eluting Stents (from the Korean DES ISR Multicenter Registry Study [KISS

There is currently no established standard treatment for in-stent restenosis (ISR) after the implantation of a drug-eluting stent (DES). The aim of this study was to investigate the efficacy of DES versus balloon angioplasty (BA) for the treatment of DES ISR in a multicenter registry cohort. After matching propensity scores of 805 patients with DES ISR treated with either DES (n = 422) or BA (n = 383), 268 matched pairs were selected and analyzed for major adverse cardiac events, a composite of death, myocardial infarction, and target-vessel revascularization, as the primary end point. Baseline clinical and lesion characteristics of the matched pairs were similar. Survival free of major adverse cardiac events at 2 years was higher with DES compared to BA (88.9% vs 78.7%, p <0.001), mainly because of higher TVR-free survival (92.4% vs 81.0%, p <0.001). Among various baseline variables, BA (hazard ratio 2.546, 95% confidence interval 1.412 to 4.593, p = 0.002) was the most important independent risk factor for recurrent target vessel revascularization, followed by acute coronary syndromes as the clinical presentation of DES ISR, and previous implantation of a sirolimus-eluting stent. Survival free of death, myocardial infarction, or stent thrombosis did not differ between the 2 groups. Whereas there was no significant difference in survival free of target vessel revascularization between DES and BA for focal ISR lesions, DES was superior to BA in diffuse ISR lesions (94.3% vs 75.2% at 2 years, p <0.001). In conclusion, compared to BA, the implantation of DES was safe and more effective in the treatment of DES ISR.

Effectiveness and Safety of the Genous Endothelial Progenitor Cell-Capture Stent in Acute ST-Elevation Myocardial Infarction

The endothelial progenitor cell (EPC)-capture stent promotes endothelialization and preliminary studies have suggested its safety and feasibility in ST-elevation myocardial infarction (STEMI). Detailed late clinical follow-up and angiographic analyses are, however, limited. We sought to determine late angiographic and clinical outcomes of the Genous EPC-capture stent in primary angioplasty. EPC-capture stents were implanted during primary angioplasty in 489 consecutive patients presenting with STEMI from 2004 through 2008. The first 100 consenting patients undergoing successful stent implantation scheduled to undergo relook coronary angiography at 6 to 12 months were enrolled. Ninety-five patients with 96 lesions were analyzed independently. Mean duration of follow-up coronary angiography was 245 days. In-stent late luminal loss measured 0.87 ± 0.67 mm. Binary restenosis (defined as >50% diameter stenosis) was 28%, with diffuse in-stent restenosis (Mehran class II) as the predominant pattern. Of 27 patients with binary restenosis, 14 (52%) were symptomatic, with 10 patients undergoing target lesion revascularization. Asymptomatic patients had significantly larger reference vessel and in-stent minimal luminal diameters (2.77 ± 0.39 vs 2.54 ± 0.44 mm, p = 0.040; 2.74 ± 0.34 vs 2.31 ± 0.72 mm, p = 0.004, respectively). Follow-up late loss and diameter stenoses were also in favor of the asymptomatic group. Major adverse cardiac event rate was 16% at a mean follow-up of 34 months. There were no cases of Academic Research Consortium-defined stent thrombosis. In conclusion, implantation of the EPC-capture stent during primary angioplasty is associated with a favorable late clinical outcome but with higher than anticipated angiographic late loss.

Diffuse in-stent restenosis of CYPHER® stent due to hypersensitivity reaction confirmed by pathohistological findings

The use of drug-eluting stents (DES) reduces the risk of repeat revascularization without increase of death and myocardial infarction compared to standard bare metal stents. However, in-stent restenosis (ISR) after DES implantation still occurs. Here, we report a rare case with a diffuse ISR after CYPHER® stent implantation because of chronic inflammation and hypersensitivity reactions, confirmed by pathohistological findings.

Six-Year Clinical Follow-up After Treatment of Diffuse In-Stent Restenosis With Cutting Balloon Angioplasty Followed by Intracoronary Brachytherapy With Liquid Rhenium-188-Filled Balloon via Transradial Approach

Long-term follow-up studies revealed a significant decline in the benefits of intracoronary radiation for in-stent restenosis. A total of 25 study and 25 contemporaneous control patients with diffuse in-stent restenosis who underwent cutting balloon angioplasty (CBA) transradially, followed by subsequent intracoronary irradiation with a liquid β-emitter Rhenium-188 (¹⁸⁸Re)-filled balloon were enrolled in the study. The mean clinical follow-up durations were 64.9 ± 13.0 and 66.3 ± 13.8 months for the irradiated and control patients, respectively. Six-month angiographic restenosis was observed in 16% (4 of 25) of the patients in the irradiated group and 48% (12 of 25) of the patients in the control groups (P = 0.03). The 6-month major adverse cardiac events (MACE) rate was 12% and 44%, respectively (P = 0.025). The 3-year follow-up angiography was performed in 16 of 21 (76%) irradiated patients and in 4 of 13 (31%) control patients who had no significant restenosis at the 6-month angiographic follow-up. Restenosis occurred in 1 of 16 (7%) irradiated patients and 2 of 4 (50%) control patients. Late target lesion revascularization was performed in 1 irradiated and 2 control patients. The MACE rate within 6 years was significantly reduced in the irradiated group (20% vs. 56%, P = 0.019). Brachytherapy using ¹⁸⁸Re-filled balloon following CBA for diffuse in-stent restenotic native coronary arteries is effective in reducing target lesion restenosis and improving long-term outcomes.

Angiographic patterns of restenosis after percutaneous intervention of chronic total occlusive lesions with drug-eluting stents

BackgroundAlthough the success rate of percutaneous coronary intervention (PCI) of chronic total occlusive (CTO) lesions is rising recently, the nature and behavior of these revascularized lesions in the real-world practice are unknown. MethodsData was collected from a prospective cohort of patients with successfully revascularized CTO lesions using drug-eluting stent (DES). Among these, patients with angiographical in-stent restenosis (ISR) were analyzed. Results58% (n=149) of the total patients (n=255) with successful PCI of CTO received 6–9months' angiographical follow-up. Angiographic ISR was identified in 36 lesions from 36 patients. There was a strong tendency towards diffuse ISR (61% of total ISR lesions) in these lesions, as compared with ISR after implantation of DES for non-CTO lesion in previous literatures. Multivariate analysis showed that post-procedural minimal lumen diameter (MLD) and total stent length were the only reliable predictors of diffuse ISR (HR 0.527 per 0.5mm increment of MLD, HR 1.262 per 10mm increment of stent length). Compared with the group with larger post-procedural MLD (>1.9mm) and shorter stent length (≤55mm), the group with smaller post-procedural MLD (≤1.9mm) and longer stent length (>55mm) carried a 9-fold higher risk of diffuse restenosis. In addition, diffuse ISR was more frequently associated with symptoms or signs of myocardial ischemia. ConclusionRevascularized CTO lesions using DES may carry a high risk of diffuse ISR, which is associated with more frequent myocardial ischemia compared with focal ISR. Post-procedural MLD and total stent length are significant predictors of these types of ISR after successful CTO intervention.

Vascular responses to the multiple overlapped paclitaxel-eluting stents for the treatment of bare-metal in-stent restenotic lesions: angiographic and intravascular ultrasound analysis from the TAXUS-V ISR Trial

Although effective coverage of coronary diffuse in-stent restenosis (ISR) lesions has warranted the use of multiple drug-eluting stents, the vessel response to paclitaxel-eluting stent (PES) overlap is not fully understood. In the TAXUS-V ISR, i.e., comparing PES versus brachytherapy for the treatment of bare-metal ISR, angiographic analyses at 9-month follow-up were available in 184 ISR lesions treated with PES. In-stent late loss in entire stented segment of multiple PES (n=50) was 0.45+/-0.48 mm, whereas that of single PES (n=134) was 0.3+/-0.47 mm, P=.06. No aneurysm was observed at overlapping PES segments at 9 months. Stent thrombosis up to 9 months was observed in one in each group (single PES, 0.7% vs. multiple PES, 1.8%; P=.47). In a subset of 30 patients, volumetric intravascular ultrasound analysis demonstrated that in-stent net volume obstruction was 12.3+/-12.4 in single PES (n=20) and 14.9+/-9.8 in multiple PES (n=10), P=.60. The changes of vessel and lumen at the overlapping PES segment were similar to those of the adjacent 5-mm segments (Deltaminimum lumen area, mm(2): -1.2+/-1.0, -1.1+/-1.1, -0.8+/-0.9, P=.48; Deltavessel volume, mm(3)/mm: -0.2+/-1.4, 0.1+/-1.7, 0.3+/-1.3, P=.37; proximal, overlap, distal segment, respectively). There was no late incomplete stent apposition at overlapping PES segments. No in vivo evidence of adverse local vessel response at the site of overlapping PES for the treatment of bare-metal ISR has been demonstrated.

Predictor of subsequent target lesion revascularization in patients with drug-eluting stent restenosis undergoing percutaneous coronary intervention

The best way to treat in-stent restenosis (ISR) after drug-eluting stent (DES) implantation remains unclear. The aim of this study was to evaluate angiographic restenosis and target lesion revascularization (TLR) at 8 months after intervention in patients with DES-ISR, and to identify predictive factors of subsequent TLR after treatment of DES-ISR. A total of 100 patients with 105 lesions underwent subsequent intervention for DES-ISR between April 2004 and January 2009. At baseline, focal and diffuse ISR were observed in 76.2% and 23.8%. DES-ISR was treated by five modalities: sirolimus-eluting stent (n=42); paclitaxel-eluting stent (n=24); balloon angioplasty (n=23); cutting balloon angioplasty (n=14); and bare-metal stent (n=2). Angiographic follow-up data were available for 95 lesions (91%). The rates of angiographic restenosis and TLR were 37.9% and 33.3%. Late loss of sirolimus-eluting stent, paclitaxel-eluting stent, cutting balloon, and balloon angioplasty were 0.50 mm, 0.49 mm, 0.93 mm, and 1.10 mm. By multivariate analysis, totally occluded ISR (OR 15.43, p=0.0005), diabetes mellitus (OR 3.45, p=0.02), and re-stenting with DES (OR 0.14, p=0.0002) were identified as independent predictors of TLR. The restenosis rate was significant in this cohort of patients with DES-ISR. Angiographic pattern of DES-ISR and diabetes mellitus are the most important predictors of TLR, whereas re-stenting with DES is protective.

Drug eluting balloons for the treatment of coronary artery disease: What can we expect?

Drug-eluting balloons (DEBs) represent an enhancement of the therapeutic repertoire for the interventional cardiologist. The therapeutic concept of DEBs is promising, notably on the basis of initial studies in patients with diffuse in-stent restenosis (ISR). At present, however, a number of questions regarding long-term efficacy and safety remain, specifically in indications other than diffuse ISR. The results of the evaluation of different substances, balloon systems and clinical indications will determine the long-term success of DEBs.

Comparison of Plain Balloon and Cutting Balloon Angioplasty for the Treatment of Restenosis With Drug-Eluting Stents vs Bare Metal Stents

The efficacy of cutting or plain balloon angioplasty (CBA or PBA) has not been analyzed for the treatment of drug-eluting stent (DES) restenosis vs bare metal stent (BMS) restenosis. The 252 in-stent restenosis (ISR) lesions in 224 consecutive patients treated by CBA (n=167) or PBA (n=85) between July 2002 and December 2007 were analyzed. At 6-month angiographic and 12-month clinical follow-up, CBA and PBA showed similar efficacies: repeat-ISR (37.0% vs 37.8%, P=0.90), late loss (0.62+/-0.60 vs 0.61+/-0.47 mm, P=0.92), and target lesion revascularization (18.3% vs 22.4%, P=0.50). This comparable efficacy was maintained for treatment in the DES-ISR and BMS-ISR subgroups. However, target lesion-related myocardial infarction (n=9) occurred more frequently in the CBA than in the PBA arm (6.2% vs 0%, P=0.03), most of which developed early after ISR treatment (n=7; 54+/-26 days). Independent predictors of repeat-ISR were diffuse ISR and smaller pretreatment minimal lumen diameter, both of which might imply heavier plaque burden in the ISR group. Plain or cutting balloon angioplasty for ISR seems to be comparable, as the angiographic or clinical endpoints were not affected by initial stent type but by parameters related to the plaque burden of the ISR lesion. However, CBA might be associated with higher risk of myocardial infarction than PBA, suggesting more attention to dual-antiplatelet therapy after its use for ISR.

Transradial approach to treat superficial femoral artery in‐stent restenosis

Transradial access reduces the incidence of access site complications of percutaneous revascularization procedures. However, in patients with peripheral vascular disease, the adoption of transradial approach for superficial femoral artery (SFA) angioplasty is usually prevented by the distance between the vascular access and the target lesions; thus, SFA angioplasty is commonly performed by transfemoral approach. Recently, low-profile balloons with extended shaft length became available, allowing to potentially address SFA lesions by transradial approach. As plain balloon angioplasty represents a valuable option for SFA in-stent restenosis treatment, we evaluated the feasibility of transradial approach in this clinical setting. Transradial balloon angioplasty of SFA diffuse in-stent restenosis was attempted in 12 patients aged 69.4 +/- 5.1 years. Six-French 125 cm long MP guiding catheters, 300 cm long 0.018'' guidewire, and low-profile 4 Fr compatible 180 cm long shaft balloons (5 and 6 mm in diameter and 80-150 mm in length) were used. The procedural success was 100%, and no complications occurred during the hospital stay. Compared with a matched group of patients in whom angioplasty was performed by trans-femoral approach, main procedural key data resulted similar except for the amount of administered contrast dye, which was slightly but significantly lower in transradial group (170 +/- 59 ml vs. 241 +/- 103, P = 0.03). In conclusion, with the currently available equipment, the transradial approach is feasible and represents a valuable alternative for treatment of patients with SFA in-stent restenosis.

Short- and long-term outcomes after treatment of diffuse in-stent restenosis with cutting balloon angioplasty followed by intracoronary β-irradiation with liquid rhenium-188-filled balloon via transradial approach

A one-step radiolabeling procedure of highly magnetic particles with the therapeutic β-emitter rhenium-188 (188Re) has been developed. Magnetic targeted carriers (MTCs) are composites of metallic iron and activated carbon that can be labeled in the presence of the reducing agent SnCl2. As MTCs are effectively targeted to solid tumors, the 188Re-MTC complex has the potential to deliver therapeutically relevant doses of radiation to tumors while minimizing radiation exposure to surrounding tissues or organs.