Predictors of restenosis in the use of helical interwoven nitinol stents to treat femoropopliteal occlusive disease

5-Year Outcomes of Drug-Coated Balloons for Peripheral Artery In-Stent Restenosis, Long Lesions, and CTOs

BACKGROUND

Long-term data on drug-coated balloon (DCB) outcomes in complex femoropopliteal atherosclerotic lesions are limited.

OBJECTIVES

The authors sought to report 5-year safety and effectiveness outcomes of a paclitaxel DCB for the treatment of de novo in-stent restenosis (ISR), long lesions (LL), or chronic total occlusions (CTOs) in the prespecified imaging cohorts of the IN.PACT Global Study.

METHODS

The IN.PACT Global study was a prospective, international single-arm study. Assessments through 5 years included freedom from clinically driven target lesion revascularization (CD-TLR), a safety composite (freedom from device- and procedure-related death to 30 days, and freedom from major target limb amputation and freedom from clinically driven target vessel revascularization within 60 months), and major adverse events.

RESULTS

The prespecified imaging cohorts enrolled 132 de novo ISR, 158 LL, and 127 CTO participants. Kaplan-Meier estimates of freedom from CD-TLR through 5 years were 58.0% (ISR), 67.3% (LL), and 69.8% (CTO). The cumulative incidences of the composite safety endpoint were 56.0% (ISR), 65.7% (LL), and 69.8% (CTO). The 5-year freedom from all-cause mortality with vital status update were 81.4% (ISR), 75.2% (LL), and 78.2% (CTO). Within the ISR cohort, 15.9% of participants experienced 2 or more TLRs, compared with 9.5% and 5.5% in the LL and CTO groups, respectively.

CONCLUSIONS

Results demonstrate long-term safety and effectiveness of this DCB in all 3 cohorts, with low reintervention rates in the LL and CTO cohorts and no safety issues. These results support the inclusion of this DCB into the treatment algorithm for complex femoropopliteal disease.

Novel Self-Expanding Interwoven Nitinol Stent for Treating Femoropopliteal Artery Disease: 12-Month Results of Single-Center First-in-Man Study

PURPOSE

To evaluate the safety and efficacy of Innospring^® stent, a novel self-expanding interwoven nitinol stent, in treating femoropopliteal atherosclerotic lesions.

METHODS

A prospective, single-center, single-arm, first-in-human study enrolled 15 patients (mean age 73.1 years; 13 men) to evaluate the safety and efficacy of the Innospring^® stent monitored by core laboratories. The inclusion criteria were claudication or ischemic rest pain, de novo lesions or nonstented restenosis, >70% stenosis, lesion length <20 cm, and a reference vessel diameter of 4-7 mm. The primary safety endpoint was 30-day major adverse events. The primary efficacy end point was stent patency at 12 months. Follow-up evaluations were conducted at 30 days, 6 months, and 12 months.

RESULTS

The lesion length was 6.1 ± 3.5 mm. Fourteen (93.3%) patients had lesions of the superficial femoral artery and 3 (20.0%) patients had lesions of the popliteal artery. Nine (60.0%) patients had moderate-to-severe calcified lesion. Technical and procedural success was 100%. No patients experienced major adverse events in the first 30 days. The Rutherford category showed significant and sustained improvement at 6 and 12 months. The 12-month follow-up radiographs obtained in 13 patients confirmed the absence of stent fractures in 100% of examinations. The cumulative primary stent patency rate at 6 and 12 months were 93.3% and 84.6%, respectively.

CONCLUSION

Stenting of the superficial femoral and popliteal arteries using the Innospring^® stent is safe and effective. This competing interwoven nitinol stent may provide superior stent integrity and fracture-resistance as well as serve areas under extreme mechanical stress.

CLINICAL IMPACT

Endovascular recanalization is a widely accepted and recommended treatment for symptomatic peripheral artery diseases. The Innospring® stent is a novel self-expanding interwoven stent containing eight nitinol wires with additional radial force, fracture-resistance, and visibility under fluoroscopy. This first-in-human study using the Innospring® stent in patients with femoropopliteal occlusive disease reported that stenting of the superficial femoral and popliteal arteries using the Innospring® stent is safe and effective. This competing interwoven nitinol stent may provide an impressive stent integrity and fracture-resistance as well as serve areas under extreme mechanical stress.

Risk Factor Analysis and Long-Term Outcomes in Patients with Endovascular Revascularization for Intermittent Claudication or Chronic Limb-Threatening Ischemia

BACKGROUND

The aim of this study is to review long-term outcome and identify risk factors for patients with peripheral arterial disease (PAD) with percutaneous transluminal angioplasty/stent as a primary treatment strategy for intermittent claudication (IC) or chronic limb-threatening ischemia (CLTI).

METHODS

A retrospective cohort study with data collected prospectively from Clinical Data Analysis and Reporting System, departmental database, and Clinical Management System. All patients who underwent endovascular procedures for PAD between January 2011 and December 2020 were identified. The primary outcomes are overall survival and amputation-free survival. Predictive factors for OS and AFS were determined using Cox Model.

RESULTS

A total number of 640 patients with PAD (IC, n = 243; CLTI, n = 377) underwent endovascular percutaneous transluminal angioplasty/stenting for PAD from January 2011 to December 2020. Patients with CLTI had a significantly higher 30 days readmission rate (18.8% vs. 6.5%, P < 0.001), emergency reoperation within 30 days (3.4% vs. 0%, P = 0.002), and death within same admission (2.7% vs. 0%, P = 0.008) compared to IC patients. The overall survival and amputation-free survival rates were significantly lower in CLTI patients (P < 0.0001 and P < 0.0001, respectively). On Cox multivariate analysis, CLTI was strongly predictive of all-cause mortality and amputation (hazard ratio [HR] 2.33 and HR 14.92, respectively). In patients with CLTI, chronic kidney disease was an independent predictor of mortality and amputation (HR 1.66 and HR 2.36, respectively). Smoking and ischemic heart disease were also independent predictors of mortality in this subgroup (HR 2.06 and HR 2.43, respectively).

CONCLUSIONS

Although patients with IC and CLTI both manifest from atherosclerotic occlusive disease of the lower limb arteries, these patients may have different clinical outcomes with significant mortality occurred in both IC and CLTI groups. In patients with IC, the risk of amputation was less than 1% at 5 years following revascularization.

Outcome benefit of arterial duplex stent imaging after superficial femoral artery stent implantation

OBJECTIVE

In-stent stenosis is a frequent complication of superficial femoral artery (SFA) endovascular intervention and can lead to stent occlusion or symptom recurrence. Arterial duplex stent imaging (ADSI) can be used in the surveillance for recurrent stenosis; however, its uniform application is controversial. In this study, we aimed to determine, in patients undergoing SFA stent implantation, whether surveillance with ADSI yielded a better outcome than in those with only ankle-brachial index (ABI) follow-up.

METHODS

We performed a retrospective analysis of all patients undergoing SFA stent implantation for occlusive disease at a tertiary care referral center between 2009 and 2016. The patients were divided into those with ADSI and those with ABI follow-up only. Life-table analysis comparing stent patency, major adverse limb events (MALEs), limb salvage, and mortality between groups was performed.

RESULTS

There were 248 patients with SFA stent implantation included, 160 in the ADSI group and 88 in the ABI group. Groups were homogeneous in clinical indications of claudication and critical limb-threatening ischemia (for ADSI, 39% and 61%; for ABI, 38% and 62%; P = .982) and TransAtlantic Inter-Society Consensus class A, B, C, and D lesions (for ADSI, 17%, 45%, 16%, and 22%; for ABI, 21%, 43%, 16%, and 20%; P = .874). Primary patency was similar between groups at 12, 36, and 56 months (ADSI, 65%, 43%, and 32%; ABI, 69%, 34%, and 34%; P = .770), whereas ADSI patients showed an improved assisted primary patency (84%, 68%, and 54%) vs ABI patients (76%, 38%, and 38%; P = .008) and secondary patency. There was greater freedom from MALEs in the ADSI group (91%, 76%, and 64%) vs the ABI group (79%, 46%, and 46%; P < .001) at 12, 36, and 56 months of follow-up. ADSI patients were more likely to undergo an endovascular procedure as their initial post-SFA stent implantation intervention (P = .001), whereas ABI patients were more likely to undergo an amputation (P < .001).

CONCLUSIONS

In SFA stent implantation, patients with ADSI follow-up demonstrate an advantage in assisted primary patency and secondary patency and are more likely to undergo an endovascular reintervention. These factors are likely to have effected a decrease in MALEs, indicating the benefit of a more universal adoption of post-SFA stent implantation follow-up ADSI.

Drug-Coated Balloon Treatment of Femoropopliteal Lesions for Patients With Intermittent Claudication and Ischemic Rest Pain: 2-Year Results From the IN.PACT Global Study

OBJECTIVES

The IN.PACT Global Study is the largest prospective, multicenter, independently adjudicated trial to evaluate a paclitaxel drug-coated balloon in patients with lifestyle-limiting claudication and/or ischemic rest pain due to atherosclerotic disease of the femoropopliteal artery and includes complex lesions beyond what are typically included in randomized controlled trials.

BACKGROUND

Randomized controlled trials have demonstrated the safety and efficacy of drug-coated balloons for the treatment of Trans-Atlantic Inter-Society Consensus Document II A and B lesions, but there is a need for large-scale prospective studies to evaluate a broader range of lesions.

METHODS

The IN.PACT Global Study enrolled 1,535 subjects, and 1,406 (1,773 lesions) were included in the pre-defined clinical cohort analysis. Freedom from clinically driven target lesion revascularization was evaluated at 24 months. The safety composite endpoint was freedom from device- and procedure-related death through 30 days and freedom from target limb major amputation and clinically driven target vessel revascularization within 24 months.

RESULTS

Mean lesion length was 12.1 cm, 35.5% were total occlusions, and 18.0% had in-stent restenosis. Freedom from clinically driven target lesion revascularization at 24 months was 83.3%, the composite safety endpoint was met in 81.7%, the 2-year all-cause mortality rate was 7.0%, and the major target limb amputation rate was 0.7%. Increased lesion length and the presence of de novo in-stent restenosis or coronary artery disease were associated with increased risk for clinically driven target lesion revascularization by 24 months.

CONCLUSIONS

This real-world study of femoropopliteal artery disease treatment with drug-coated balloons confirmed positive findings reported from more strictly designed randomized controlled trials and showed that outcomes are durable in this population up to 2 years after treatment. (IN.PACT Global Clinical Study; NCT01609296).

Drug-Coated Balloon Treatment for Femoropopliteal Artery Disease

Background The IN.PACT Global Study was an international prospective single-arm clinical trial to evaluate the safety and effectiveness of a drug-coated balloon in the treatment of atherosclerotic disease of the superficial femoral and/or popliteal arteries (P1-P3) in subjects with intermittent claudication and/or rest pain. Prespecified subjects were selected for core-laboratory-adjudicated duplex ultrasound imaging, including a subcohort with long lesions (≥15 cm). Methods and Results Subjects were followed for 12 months. The primary safety end point was a composite of freedom from device- and procedure-related mortality through 30 days and freedom from major target limb amputation and clinically-driven target vessel revascularization through 12 months. An independent Clinical Events Committee adjudicated all adverse events. The primary effectiveness end point was primary patency at 12 months (by duplex ultrasound). The long lesion imaging cohort had 157 subjects (164 lesions). Mean lesion length was 26.40±8.61 cm. Provisional stents were implanted in 39.4% (63/160) of lesions. Primary patency by Kaplan-Meier estimate was 91.1%, and freedom from clinically-driven target lesion revascularization was 94.2% at 12 months. The primary safety composite end point was achieved by 94.0% (126/134) of subjects. There were no device- or procedure-related deaths or major target limb amputations. Conclusions The IN.PACT Admiral drug-coated balloon was safe and highly effective at 12 months after treatment in a rigorous independently adjudicated analysis of real-world subjects with lesions ≥15 cm in the superficial femoral and/or popliteal arteries (P1-P3). CLINICAL TRIAL REGISTRATION URL: https://www.clinicaltrials.gov . Unique identifier: NCT01609296.

Real-World Results of Supera Stent Implantation for Popliteal Artery Atherosclerotic Lesions: 3-Year Outcome

BACKGROUND

Reports our experience for the first 50 cases of use of Supera stent for popliteal atherosclerotic lesions treatment.

METHODS

This prospective single-arm trial enrolled the first 50 limbs (46 patients) treated in our center with a Supera stent for symptomatic atherosclerotic disease of the popliteal artery. Also, a follow-up of 36 months is reported.

RESULTS

The mean preoperative ankle-brachial index increased from 0.38 ± 0.37 before intervention to 0.63 ± 0.46 postoperatively at 12 months (P = 0.014), 0.66 ± 0.39 at 24 months (P = 0.023), and 0.74 ± 0.46 at 36 months (P = 0.029). Primary patency at 12, 24, and 36 months were 89.6%, 72.3%, and 70.2%, and primary assisted patency was 93.8%, 87.2%, and 85.1%, respectively, by Kaplan-Meier estimates. After 3 years of follow-up, age <75 years (P = 0.034) and Trans-Atlantic Inter-Society Consensus (TASC)-II D lesions (P = 0.041) constituted risk factors for stent occlusion. During the follow-up of the patients, none of them developed stent fracture as evidenced on plain radiographs during follow-up. Implantation defects did not constitute a risk factor for stent restenosis.

CONCLUSIONS

Based on the results of this study, Supera stent has shown an excellent 3-year patency in this difficult-to-treat anatomic segment. In our experience, younger patients and complex lesions (TASC-II type D) were positive significant predictors for restenosis. In our cohort, post deployment stent conformation did not influence patency. Nevertheless, further investigations, including randomized studies comparing the Supera stent with other stent platforms, drug eluting angioplasty, or atherectomy devices, are mandatory.

The presence of long and heavily calcified lesions predisposes for fracture in patients undergoing stenting of the first part of the subclavian artery

OBJECTIVE

To determine the prevalence and risk factors of subclavian artery stent fractures and to investigate their impact on in-stent restenosis development.

METHODS

One hundred eight patients (65 females; median age, 58.3 years [interquartile range, 53.4-65.5 years]) with steno-occlusive disease of the first part of the subclavian artery who underwent stenting (N = 108 stents; balloon-expandable, 83.3%; self-expandable, 16.7%) between 2005 and 2015 and returned for a fluoroscopic examination of the implanted stents in 2017 were included in our study. Fractures were type I (single strut fracture), type II (multiple strut fractures without deformation), type III (multiple strut fractures with deformation), type IV (multiple strut fractures with acquired transection but without gap), or type V (multiple strut fractures with acquired transection with gap in the stent body). Stent patency was monitored by duplex ultrasound imaging. The Mann-Whitney U and Fisher's exact tests; Kaplan-Meier, receiver operating characteristic, and logistic regression analyses; as well as a log-rank test were used as statistical methods.

RESULTS

The median follow-up was 73.8 months (interquartile range, 35.6-104.2 months). Thirty-eight fractures (35.2%) were detected; fractures were type I in 13, type II in 12, type III in 6, type IV in 4, and type V in 3 cases. Multivariable logistic regression analysis revealed the presence of long (≥20 mm) lesions (odds ratio, 3.3; 95% confidence interval, 1.3-8.4; P = .012) and heavy calcification (odds ratio, 4.7; 95% confidence interval, 1.7-12.7; P = .002) to be significant independent predictors of stent fracture. The primary patency rates were significantly worse (P = .035) in patients with stent fracture compared with those without stent fracture.

CONCLUSIONS

Stent fractures frequently occur. Patients with long and/or heavily calcified lesions require closer follow-up.

Preprocedural Mean Platelet Volume Level Is a Predictor of In-Stent Restenosis of the Superficial Femoral Artery Stents in Follow-Up

Background

The mean platelet volume (MPV), the most commonly used measure of the platelet size, is a cheap and easy-to-use marker of the platelet activation. We aimed to evaluate the relationship between preprocedural MPV and other hematologic blood count parameters and in-stent restenosis in patients with superficial femoral artery (SFA) stenting.

Methods and Results

The consecutive 118 patients who successfully underwent endovascular stenting of the SFA were enrolled retrospectively in the study. The mean follow-up was 23 ± 12 months. The in-stent restenosis was observed in 42 patients (35.6%). There were no statistically significant differences between the restenosis group and no-restenosis group in terms of age, gender, and smoking (p=0.116, p=0.924, and p=0.428, resp.). In the restenosis group, the MPV level was markedly higher than that in the no-restenosis group, and it was statistically significant (p < 0.001). According to the ROC curve analysis, the optimal cutoff value of the MPV to determine the restenosis was >8.7 fL, and the level of the MPV >8.7 fL was a strong predictor of the restenosis (p < 0.001) in logistic regression analysis.

Conclusions

The measurement of the preprocedural MPV levels may help to identify high-risk patients for development of the in-stent restenosis. These patients may benefit from an aggresive antiplatelet therapy and close follow-up.

Endovascular Treatment of Severely Calcified Femoropopliteal Lesions Using the “Pave-and-Crack” Technique: Technical Description and 12-Month Results

Purpose: To report midterm results of the “pave-and-crack” technique to facilitate safe and effective scaffolding of heavily calcified femoropopliteal lesions in preparation for delivery of a Supera interwoven stent. Methods: Data were collected retrospectively on 67 consecutive patients (mean age 71±8 years; 54 men) treated with this technique between November 2011 and February 2017 at a single center. A third (22/64, 34%) of the patients had critical limb ischemia (CLI). Most lesions were TASC D (52/67, 78%), and the majority were occlusions (61/66, 92%). The mean lesion length was 26.9±11.2 cm. Nearly two-thirds (40/64, 62%) had grade 4 calcification (Peripheral Arterial Calcium Scoring System). To prepare for Supera stenting, the most heavily calcified segments of the lesion were predilated aggressively to obliterate recoil. A Viabahn stent-graft was then implanted to “pave” the lesion and protect from vessel rupture as aggressive predilation continued until the calcified plaque was “cracked” before lining the entire lesion with a Supera stent. Patency and target lesion revascularization (TLR) rates were estimated using the Kaplan-Meier method. Results: Procedural success was achieved in 100% and technical success (residual stenosis <30%) in 98% (66/67). The mean cumulative stent lengths were 16±9 cm for the Viabahn and 23±12 cm for the Supera. Only 2 complications occurred (distal embolization and access-site pseudoaneurysm). Two CLI patients died within 30 days, and 3 patients (all claudicants) underwent a TLR. Patients were followed for a mean 19±18 months, during which another 2 CLI patients died and 1 patient had a major amputation. One-year primary and secondary patency estimates were 79% and 91%, respectively; freedom from TLR was 85%. Conclusion: Despite severe lesion calcification, patients experienced high technical success and a safe and durable therapy at midterm follow-up with the femoropopliteal “pave-and-crack” technique.

Percutaneous Therapies for Peripheral Artery Disease

Percutaneous therapies for peripheral artery disease continue to evolve with new techniques and devices. Although guidelines-recommended therapies have impacted cardiovascular morbidity and mortality, endovascular interventions have been shown to reduce limb pain, improve quality of life, and prolong walking distance for those with claudication and to reduce amputation rates among those with critical limb ischemia. Novel devices such as drug-eluting stents and drug-coated balloons have improved patency for moderate-length lesions, whereas others allow treatment of heavily calcified and tortuous segments. New adjunctive devices to cross lesions and reduce or modify associated plaque have also been developed, although level 1 data regarding their efficacy are sparse. There has also been a better mechanistic understanding of lower extremity endovascular treatment using tools such as intravascular ultrasound. This information has highlighted the need for better stent size selection for the femoropopliteal arterial segments and larger balloon diameters for the tibial arteries. Moreover, a wound perfusion approach with direct in-line flow, the so-called angiosome approach, and reconstruction of the pedal loop have been advocated for improved wound healing. Technical advances such as the tibiopedal access and reentry methods have allowed crossing of lesions that were considered no option for the endovascular approach in the past. Collectively, there has been increased awareness, interest, and commitment by various specialty societies and organizations to advance the treatment of peripheral artery disease and critical limb ischemia. This is also evident by the recent coalition of 7 professional societies and organizations that represented >150 000 allied health professionals and millions of patients with peripheral artery disease at the 2015 Centers for Medicaid and Medicare Services Medicare Evidence Development and Coverage Analysis Committee meeting. The percutaneous therapies for peripheral artery disease continue to evolve with longer follow-up with randomized data and larger prospective registries. In the future, it is hopeful that we will treat the lower extremity arteries according to segments, taking into account plaque morphology, luminal versus subintimal crossing, location, and stenotic versus occlusive disease. Until then, we must identify the most cost-effective, efficacious, and safe treatment for each patient. The goal of this article is to aid the practicing vascular specialist consider the optimal choices for the management of patients with vascular disease.

Evolution of patency rates of self-expandable bare metal stents for endovascular treatment of femoro-popliteal arterial occlusive disease: Does stent design matter?

OBJECTIVE

To analyse the patency rates of femoro-popliteal stenting with different self-expandable Nitinol stent-designs.

METHODS

Two hundred and twenty-two patients (142 (64%) male; age 72.4 ± 11.6 years) with symptomatic femoro-popliteal peripheral arterial occlusive disease (PAOD) underwent percutaneous transluminal angioplasty (PTA) and stenting with three different Nitinol stents (interwoven IW: n = 70; closed-cell CC: n = 85; open-cell OC: n = 67). One-year post-procedural target lesion revascularization (TLR_12M) rates were investigated with regard to co-morbidities: diabetes (DBM), hyperlipidaemia (HLP), hypertension (RR), coronary artery disease (CAD) and degree of calcification.

RESULTS

Twelve-month follow-up data were available for 60, 69 and 50 patients in the IW, OC and CC groups (179 patients in total). The cumulative patency (IW: 52 (86.7%); OC: 50 (72.5%); CC: 23 (46.0%); P < 0.001) and the TLR_12M rates (IW: 8 (13.3%); OC: 19 (27.5%); CC: 27 (54.0%); P < 0.001) differed significantly, as did the subgroup analyses (DBM: P = 0.05; RR: P = 0.003; HLP: P = 0.005; CAD: P = 0.02; localization: P < 0.001; calcification: P < 0.001), with the best patency for the IW stent and the highest TLR_12M for the CC stent.

CONCLUSION

The interwoven stent-design was superior to the standard open- and closed-cell stent-designs in endovascular treatment of femoro-popliteal PAOD in a follow-up period of 12 months.

KEY POINTS

• Results of femoro-popliteal stenting are still unsatisfactory. • Comparative studies for currently available different Nitinol stent-designs are lacking. • This is a first comparative study on long-term patency of different Nitinol stent-designs. • Interwoven stent-design leads to improved long-term patency. • Interwoven stent-design leads to lower TLR than other stent-designs.

[Stent-assisted recanalization of femoropopliteal arterial occlusive disease. Influence of stent design on patency rates]

BACKGROUND

Despite enormous technical progress the results of endovascular treatment of the femoropopliteal vasculature are unsatisfactory and its role is still controversially discussed. In the past decade numerous new stent designs have come onto the market but it is unclear whether they have benefits with respect to patency rates.

OBJECTIVES

Comparison of published data on patency rates and target lesion revascularization rates after use of different stent designs in the femoropopliteal vasculature.

MATERIAL AND METHODS

Analysis of 25 published studies and registries from 2006 to 2015 for classical open-cell stents, interwoven stents and partially or fully covered stents.

RESULTS AND CONCLUSION

The published data are heterogeneous and comparative studies for different stent designs are completely missing. Over the past decade the patency rates after femoropopliteal stenting could be improved. According to available data stenting of short lesions < 5 cm does not show any benefit compared to isolated balloon angioplasty. Primary stenting is now recommended for intermediate and longer lesions > 6.4 cm. Due to the heterogeneity of published data a clear benefit for a specific stent design is not obvious; however, data for interwoven stents are promising and show a tendency towards improved patency, at least for certain lesions. Randomized controlled comparative trials are needed to confirm this result.