Drug-Eluting Versus Bare-Metal Stent Implantation With or Without Cilostazol in the Treatment of the Superficial Femoral Artery

The effect of cilostazol on late outcomes after endovascular treatment for occlusive femoropopliteal disease

OBJECTIVE

Restenosis and late occlusion remain a significant problem for endovascular treatment of peripheral artery disease. This meta-analysis aims to evaluate the effect of cilostazol on late outcomes after endovascular repair of occlusive femoropopliteal disease.

METHODS

A systematic literature review was conducted conforming to established criteria to identify articles published up to September 2023 evaluating late outcomes after endovascular treatment for atherosclerotic femoropopliteal disease. Eligible studies should compare outcomes between patients treated with cilostazol and patients not treated with cilostazol. Both prospective and retrospective studies were eligible. Late outcomes included primary patency (PP), restenosis, target lesion revascularization (TLR), and major amputation during follow-up.

RESULTS

Overall, 10 clinical studies were identified for analysis including 4721 patients (1831 with cilostazol vs 2890 without cilostazol) that were treated for 5703 lesions (2235 with cilostazol vs 3468 without cilostazol). All studies were performed in Japan. Mean follow-up was 24.1 ± 12.5 months. Cilostazol was associated with a lower risk for restenosis (pooled odds ratio [OR], 0.503; 95% confidence interval [CI], 0.383-0.660; P < .0001). However, no association was found between cilostazol and TLR (pooled OR, 0.918; 95% CI, 0.300-2.812; P = .881) as well as major amputation (pooled OR, 1.512; 95% CI, 0.734-3.116; P = .263). Regarding primary patency, cilostazol was associated with a higher 12-month PP (OR, 3.047; 95% CI, 1.168-7.946; P = .023), and a higher 36-month PP (OR, 1.616; 95% CI, 1.412-1.850; P < .0001). No association was found between cilostazol and mortality during follow-up (pooled OR, .755; 95% CI, 0.293-1.946; P = .561).

CONCLUSIONS

Cilostazol seems to have a positive effect on 1- to 3-year PP and restenosis rates among patients treated endovascularly for atherosclerotic femoropopliteal disease. A positive effect on TLR and amputation risk was not verified in this review.

A Systematic Review and Meta-Analysis of Efficacy and Safety of Cilostazol Prescription in Patients With Femoropopliteal Peripheral Artery Disease After Endovascular Therapy

PURPOSE

The purpose of this study is to assess the efficacy and safety of cilostazol prescription in patients with femoropopliteal peripheral artery disease (PAD) after endovascular therapy (EVT).

MATERIALS AND METHODS

We conducted a systematic review and meta-analysis of all studies reporting the outcomes of cilostazol after femoropopliteal EVT of PAD up to September 2022. Clinical outcomes of interest included primary patency, in-stent restenosis (ISR), vessel re-occlusion, freedom from target lesion revascularization (TLR), repeat revascularization, all-cause mortality, amputation, major adverse cardiovascular events (MACEs) and major adverse limb events (MALEs), and bleeding complication.

RESULTS

A total of 4 randomized controlled trials (RCTs) and 8 observational studies containing a total of 4898 patients met the inclusion criteria and were included in this systematic review and meta-analysis. We found that the use of cilostazol was associated with higher primary patency after femoropopliteal artery EVT (odds ratio [OR]=1.67, 95% confidence interval [CI]=1.50-1.87, p<0.001, I2=33.2%), a lower risk of ISR (OR=0.43, 95% CI=0.29-0.63, p<0.001, I2=37.6%), repeat revascularization (OR=0.43, 95% CI=0.24-0.76, p<0.005, I2=27.4%), and vessel re-occlusion (OR=0.59, 95% CI=0.38-0.93, p<0.05, I2=0%). There was an increase in freedom from TLR rate (OR=2.19, 95% CI=1.58-3.05, p<0.001, I2=0%), as well as a reduction in the occurrence of MALEs (OR=0.50, 95% CI=0.29-0.85, p<0.05, I2=0%). However, there was no significant difference in amputation, MACEs, all-cause mortality, and major bleeding complications. Subgroup analysis showed that cilostazol treatment in patients with femoropopliteal drug-eluting stents (DES) implantation remained associated with higher primary patency and a lower risk of ISR.

CONCLUSIONS

After EVT of femoropopliteal artery lesions, additional oral cilostazol enhances primary patency, reduces the occurrences of ISR and vessel re-occlusion, diminishes the risks associated with MALEs, lowers the need for repeat revascularization, and increases freedom from TLR rates. However, it does not impact amputation, MACEs, all-cause mortality, or major bleeding complications. These findings suggest cilostazol as a potentially safe and effective adjunct therapy in patients with femoropopliteal PAD after EVT.

CLINICAL IMPACT

After undergoing endovascular therapy (EVT) for femoropopliteal artery lesions, the addition of cilostazol to antiplatelet therapy can significantly improve primary patency, reducing the incidence of in-stent restenosis, repeat revascularization, vessel re-occlusion, and major adverse limb events while increasing freedom from target lesion revascularization rate. The simultaneous use of drug-eluting stents in the femoropopliteal artery lesions, combined with cilostazol, potentially results in a synergistic anti-stenotic effect. This therapeutic approach does not appear to be associated with an increased risk of major bleeding events or all-cause mortality. These findings provide additional evidence supporting the treatment of anti-stenosis in patients with femoropopliteal artery lesions after EVT.

Different drugs in drug-eluting stents for peripheral artery disease: a systematic evaluation and Bayesian meta-analysis

Drug-eluting stents (DESs) have become the first-line treatment for symptomatic peripheral arterial disease (PAD). Currently, there are many types of DESs on the market. The same type of DESs has different concentrations, and various drugs in them show uneven efficacy. The selection of DESs remains controversial. This study was aimed at comparing the long-term real-world outcomes of different DESs in the treatment of peripheral arterial occlusive disease (PAOD). The databases including Cochrane Library, Embase, and PubMed were searched with a time frame until March 25, 2023. The primary patency (PP) and target lesion revascularization (TLR) at 6 months were used as the primary endpoints. A total of 32 studies (5467 patients) were eligible. At the six-month follow-up, DES-Evero 1 ug/mm2 ranked first in terms of PP, with a significant difference from BMSs (RR [95% CI] = 1.6). DES-Siro 0.9 ug/mm2, DES-Siro 1.4 ug/mm2, DES-Siro 1.95 ug/mm2, DES-PTX 0.167 ug/mm2, DES-PTX 1 ug/mm2 and covered stents (CSs) showed significantly better PPs than BMSs. In terms of TLR, DES-Siro 0.9 ug/mm2 (0.31) ranked first, and DES-Evero 1 ug/mm2 ranked last. Among the treatment modalities for PAD, different DESs showed overall encouraging results in improving PP and TLR compared with BMSs. DES-Evero 1 ug/mm2 showed the best PP, but it had the highest reintervention rate at 6 months. Sirolimus-eluting stents were not always more effective with higher concentrations of sirolimus. Among various DESs, sirolimus-eluting stents and everolimus-eluting stents were superior to paclitaxel-eluting stents.

Mortality, Safety, and Effectiveness of Paclitaxel-Containing Balloons and Stents in the Femoropopliteal Artery: Systematic Review and Meta-Analysis of Randomized Controlled Trials since 2018

PURPOSE

To provide an updated systematic review and meta-analysis of safety and effectiveness outcomes with paclitaxel-containing devices.

MATERIALS AND METHODS

A systematic review and meta-analysis of randomized controlled trials (RCTs) investigating paclitaxel-containing balloons or stents in the treatment of femoropopliteal disease was performed. Pooled risk ratio (RR) was calculated using the inverse-variance, random-effects model in the assessment of primary patency, all-cause mortality, target limb major amputation, target lesion revascularization (TLR), and thrombosis.

RESULTS

In total, 19 RCTs were included comprising 4,284 participants. All-cause mortality rates did not differ significantly between the 2 arms at 12 months (RR, 1.06; 95% confidence interval [CI], 0.66-1.72; P = .80), 24 months (RR, 0.92; 95% CI, 0.56-1.50; P = .73), 36 months (RR, 1.21; 95% CI, 0.65-2.25; P = .55), or 48-60 months (RR, 0.95; 95% CI, 0.66-1.39; P = .81) after intervention. Primary patency was significantly higher at 12 months in the paclitaxel-containing arm: 80.92% (1,438/1,777) versus 57.48% (607/1,056) in the control arm (RR, 1.44; 95% CI, 1.30-1.59; P < .00001).

CONCLUSIONS

The present study demonstrates no statistically significant difference in all-cause mortality, target limb major amputation, or thrombosis with paclitaxel drug-eluting therapy to the femoropopliteal region. Additionally, improved and durable patency rates with a statistically significantly lower risk of clinically driven TLR with paclitaxel drug-eluting therapy have been demonstrated.

Randomized clinical Trial Comparing drug Eluting Stent Zilver PTX® Versus Bare Metal Stent Zilver Flex® for Treatment of Lesions in Femoral and Popliteal Arteries in Chronic Limb Threatening Ischemia

OBJECTIVE

Drug eluting stents (DES) might improve the results of stenting in the femoropopliteal (FP) segment, but randomized data between DES and BMS in the treatment of patients with chronic limb threatening ischemia (CLTI) is lacking. The aim of this study was to perform a randomized comparison, between DES and bare metal stent (BMS) implantation in a subgroup of CLTI patients with lesions in the superficial femoral artery (SFA) and the P1-P2 portion of the popliteal artery.

METHODS

Patients presenting with CLTI scheduled for endovascular treatment of FP lesions were randomly assigned by blinded envelopes 1:1 in a single blinded, parallel group design to DES or BMS after lesion crossing. Primary endpoints were target lesion revascularization (TLR) at 12 and 24 months and primary patency at 12 and 24 months. Secondary endpoints were technical success (TS), clinical success, secondary patency at 12 and 24 months, limb salvage, serious adverse events (SAE) at 24 month and survival at five years.

RESULTS

A total of 48 CLTI patients and 49 limbs, were enrolled, 22 in the BMS group and 27 in the DES group. Demographics, comorbidities, and Rutherford class were similar in both treatment arms. The overall rate of total occlusions was 96% and the corresponding overall median lesion length was 240 mm. No patients were lost to follow up. No significant differences were detected between groups regarding TLR and primary patency. The overall primary patency at 12 and 24 months was 42.9% and 36.7% respectively and the overall freedom from TLR was 67.3% and 61.2% respectively. The results in the two groups were also similar regarding secondary outcomes.

CONCLUSIONS

This single centre, randomized study could not demonstrate superiority of DES compared to BMS when treating long FP lesions in patients with CLTI but was limited by insufficient patient inclusion.

Meta-analysis of outcomes from drug-eluting stent implantation in femoropopliteal arteries

OBJECTIVE

In recent years, studies of drug-eluting stent (DES) for femoropopliteal artery diseases (FPADs) have been gradually published. To explore whether this type of stent is superior to the traditional bare metal stent (BMS), we performed this study.

METHODS

A systematic search for randomized controlled trials (RCTs) in Excerpta Medica Database (Embase), PubMed, Web of Science (WOS), and Cochrane Library was performed on November 29, 2022. We innovatively adopted the hazard ratio (HR), the most appropriate indicator, as a measure of the outcomes that fall under the category of time-to-event data. The HRs was extracted directly or indirectly. Then, the meta-analyses using random effects model were performed. The bias risks of included papers were assessed by the Cochrane Risk of Bias 2.0 tool. This study was registered on the PROSPER platform (CRD42023391944) and not funded.

RESULTS

Seven RCTs involving 1,889 participants were found. After pooled analyses, we obtained results without propensity on each of the following 3 outcomes of interest: in-stent restenosis (ISR) -free survival, primary patency (PP) survival, and target lesion revascularization (TLR) -free survival (P >0.05, respectively). Because the results of pooled analyses of the other two outcomes of interest (all-cause death free survival and clinical benefit survival) had high heterogeneity both, they were not accepted by us.

CONCLUSION

For FPADs, the DES has not yet demonstrated superiority or inferiority to BMS, in the ability to maintain PP, avoid ISR and TLR.

Long-Term Patient Outcomes After Femoropopliteal Peripheral Vascular Intervention in Patients With Intermittent Claudication

BACKGROUND

In patients with intermittent claudication (IC), short-term amputation rates from clinical trial data following lower extremity femoropopliteal (FP) peripheral vascular intervention (PVI) are <1% with unknown longer-term rates.

OBJECTIVES

The aim of this study was to identify revascularization and amputation rates following PVI in the FP segment and to assess 4-year amputation and revascularization rates after FP PVI for IC.

METHODS

From 2016 to 2020, 19,324 patients undergoing FP PVI for IC were included from the PINC AI Healthcare Database and evaluated by treatment level (superficial femoral artery [SFA], popliteal artery [POP], or both). The primary outcome was index limb amputation (ILA) assessed by Kaplan-Meier estimate. The secondary outcomes were index limb major amputation and repeat revascularization. HRs were estimated using Cox proportional hazard regression.

RESULTS

The 4-year index limb amputation rate following FP PVI was 4.3% (95% CI: 4.0-4.7), with a major amputation rate of 3.2% (95% CI: 2.9-3.5). After POP PVI, ILA was significantly higher than SFA alone (7.5% vs 3.4%) or both segment PVI (5.5%). In multivariate analysis, POP PVI was associated with higher ILA rates at 4 years compared with isolated SFA PVI (HR: 2.10; 95% CI: 1.52-2.91) and index limb major amputation (HR: 1.98; 95% CI: 1.32-2.95). Repeat FP revascularization rates were 15.2%; they were highest in patients undergoing both SFA and POP PVI (18.7%; P < 0.0001) compared with SFA (13.9%) and POP (17.1%) only.

CONCLUSIONS

IC patients undergoing FP PVI had 4-year rates of index limb repeat revascularization of 16.7% and ILA rates of 4.3%. Further risk factors for amputation requires further investigation.

Endovascular revascularization strategies for aortoiliac and femoropopliteal artery disease: a meta-analysis

AIMS

Optimal endovascular management of intermittent claudication (IC) remains disputed. This systematic review and meta-analysis compares efficacy and safety outcomes for balloon angioplasty (BA), bare-metal stents (BMS), drug-coated balloons (DCB), drug-eluting stents (DES), covered stents, and atherectomy.

METHODS AND RESULTS

Electronic databases were searched for randomized, controlled trials (RCT) from inception through November 2021. Efficacy outcomes were primary patency, target-lesion revascularization (TLR), and quality-of-life (QoL). Safety endpoints were all-cause mortality and major amputation. Outcomes were evaluated at short-term (<1 year), mid-term (1-2 years), and long-term (≥2 years) follow-up. The study was registered on PROSPERO (CRD42021292639). Fifty-one RCTs enrolling 8430 patients/lesions were included. In femoropopliteal disease of low-to-intermediate complexity, DCBs were associated with higher likelihood of primary patency [short-term: odds ratio (OR) 3.21, 95% confidence interval (CI) 2.44-4.24; long-term: OR 2.47, 95% CI 1.93-3.16], lower TLR (short-term: OR 0.33, 95% CI 0.22-0.49; long-term: OR 0.42, 95% CI 0.29-0.60) and similar all-cause mortality risk, compared with BA. Primary stenting using BMS was associated with improved short-to-mid-term patency and TLR, but similar long-term efficacy compared with provisional stenting. Mid-term patency (OR 1.64, 95% CI 0.89-3.03) and TLR (OR 0.50, 95% CI 0.22-1.11) estimates were comparable for DES vs. BMS. Atherectomy, used independently or adjunctively, was not associated with efficacy benefits compared with drug-coated and uncoated angioplasty, or stenting approaches. Paucity and heterogeneity of data precluded pooled analysis for aortoiliac disease and QoL endpoints.

CONCLUSION

Certain devices may provide benefits in femoropopliteal disease, but comparative data in aortoiliac arteries is lacking. Gaps in evidence quantity and quality impede identification of the optimal endovascular approach to IC.

Safety of paclitaxel-coated devices in the femoropopliteal arteries: A systematic review and meta-analysis

Background

Clinical benefit of paclitaxel-coated devices for patients with peripheral arterial disease has been confirmed in randomized controlled trials (RCTs). A meta-analysis published in 2018 identified late mortality risk over a long follow-up period due to use of paclitaxel-coated devices in the femoropopliteal arteries, which caused enormous controversy and debates globally. This study aims to further evaluate the safety of paclitaxel-coated devices by incorporating the most recently published data.

Methods

We searched for candidate studies in PubMed (MEDLINE), Scopus, EMBASE (Ovid) online databases, government web archives and international cardiovascular conferences. Safety endpoints of interest included all-cause mortality rates at one, two and five years and the risk ratio (RR) was used as the summary measure. The primary analysis was performed using random-effects models to account for potential clinical heterogeneity.

Findings

Thirty-nine RCTs including 9164 patients were identified. At one year, the random-effects model yielded a pooled RR of 1.06 (95% CI [0.87, 1.29]) indicating no difference in short-term all-cause deaths between the paclitaxel and control groups (crude mortality, 4.3%, 214/5025 versus 4.5%, 177/3965). Two-year mortality was reported in 26 RCTs with 382 deaths out of 3788 patients (10.1%) in the paclitaxel arm and 299 out of 2955 patients (10.1%) in the control arm and no association was found between increased risk of death and usage of paclitaxel-coated devices (RR 1.08, 95% CI [0.93, 1.25]). Eight RCTs recorded all-cause deaths up to five years and a pooled RR of 1.18 (95% CI [0.92, 1.51]) demonstrated no late mortality risk due to use of paclitaxel-coated devices (crude mortality, paclitaxel 18.2%, 247/1360 versus control 15.2%, 122/805).

Conclusions

We found no significant difference in either short- or long-term all-cause mortalities between patients receiving paclitaxel-coated and uncoated devices. Further research on the longer-term safety of paclitaxel usage (e.g., 8- or 10-year) is warranted.

Registration

PROSPERO, CRD42021246291.

Cilostazol effectiveness in reducing drug-coated stent restenosis in the superficial femoral artery: The ZERO study

Purpose

Drug-eluting stents (DESs) play an important role in endovascular therapy (EVT) for femoropopliteal (FP) lesions. Cilostazol improves patency after bare-metal nitinol stent (BNS) implantation for femoropopliteal lesions. This study aimed to establish whether cilostazol is effective in improving the patency of DESs and determine whether BNS or DESs with or without cilostazol are more effective in improving the 12-month patency after EVT for FP lesions.

Materials and methods

In this prospective, open-label, multicenter study, 85 patients with symptomatic peripheral artery disease due to de novo FP lesions were enrolled and treated with DESs with cilostazol from eight cardiovascular centers between April 2018 and May 2019. They were compared with 255 patients from the DEBATE SFA study, in which patients were randomly assigned to the BNS, BNS with cilostazol, or DES groups. The primary endpoint was the 12-month patency rate using duplex ultrasound (peak systolic velocity ratio < 2.5). This study was approved by the ethics committee of each hospital.

Results

The 12-month patency rates for the BNS, BNS with cilostazol, DES, and DES with cilostazol groups were 77.6%, 93.1%, 82.8%, and 94.2%, respectively (p = 0.007). The 12-month patency rate was higher in the DES with cilostazol group than in the DES group (p = 0.044). In small vessels, the DES with cilostazol group had a higher patency rate than the DES group (100.0% vs. 83.4%, p = 0.023).

Conclusions

DES with cilostazol showed better patency than DES alone. Cilostazol improved patency after EVT with DES in FP lesions and small vessels.

Clinical trial registration

University Hospital Medical Information Network Clinical Trials Registry (no. UMIN 000032473).

Network Analysis of Endovascular Treatment Strategies for Femoropopliteal Arterial Occlusive Disease

PURPOSE

Endovascular treatment of femoropopliteal arterial diseases remains controversial. We conducted a Bayesian network meta-analysis of randomized controlled trials aiming to investigate the efficacy differences between paclitaxel- or sirolimus-eluting stents, covered stents, drug-coated balloons, bare metal stents, and percutaneous transluminal angioplasty.

METHOD

MEDLINE, Embase, Ovid, and other relevant online material were searched up to October 21, 2020. Primary endpoints were primary patency and target lesion revascularization at 6, 12, and more than 24 months.

RESULTS

Thirty-eight eligible trials included 6026 patients. In terms of primary patency, drug eluting stents were ranked as the most effective treatment based on the surface under the cumulative ranking curve values at 6 (80.6), 12 (78.4), and more than 24 months (96.5) of follow-ups. In terms of target lesion revascularization, drug eluting stents were ranked as the most effective treatment based on the surface under the cumulative ranking curve values at 6 (90.3), 12 (71.3), and more than 24 months (82.1) of follow-ups. Covered stents and bare metal stents had higher ranks in target lesion revascularization than those in primary patency. Sirolimus stents had a higher rank than paclitaxel stents.

CONCLUSION

Drug eluting stents showed encouraging results in primary patency rates and freedom from target lesion revascularization at all phases of follow-up for femoropopliteal arterial diseases. Sirolimus stents appear to be more effective in femoropopliteal segment than paclitaxel stent.

Principal predictors of major adverse limb events in diabetic peripheral artery disease: A narrative review

Background and aims

The increasing prevalence of diabetes mellitus is causing a massive growth of peripheral artery disease incidences, a disabling complication of diabetic atherosclerosis, which leads often to the amputation of the affected limb. Critical limb ischemia is the terminal disease stage, which requires a prompt intervention to relieve pain and save limbs. However, patients undergoing revascularization often suffer from cardiovascular, cerebrovascular and major adverse limb events with poor outcomes. Furthermore, the same procedure performed in apparently similar patients has various outcomes and lack of an outcome predictive support causes a high lower limb arterial revascularization rate with disastrous effects for patients. We collected the main risk factors of major adverse limb events in a more readable and immediate format of the topic, to propose an overview of parameters to manage effectively peripheral artery disease patients and to propose basics of a new predictive tool to prevent from disabling vascular complications of the disease.

Methods

Most recent and updated literature about the prevalence of major adverse limb events in peripheral artery disease was reviewed to identify possible main predictors.

Results

In this article, we summarized major risk factors of limb revascularization failure and disabling vascular complications collecting those parameters principally responsible for major adverse limb events, which provides physio-pathological explanation of their role in peripheral artery disease.

Conclusion

We evaluated and listed a panel of possible predictors of MALE (Major Adverse Limb Event) in order to contribute to the development of a predictive score, based on a summary of the main risk factors reported in scientific articles, which could improve the management of peripheral artery disease by preventing vascular accidents.

Highly Selective PPARα (Peroxisome Proliferator-Activated Receptor α) Agonist Pemafibrate Inhibits Stent Inflammation and Restenosis Assessed by Multimodality Molecular-Microstructural Imaging

BACKGROUND

New pharmacological approaches are needed to prevent stent restenosis. This study tested the hypothesis that pemafibrate, a novel clinical selective PPARα (peroxisome proliferator‐activated receptor α) agonist, suppresses coronary stent‐induced arterial inflammation and neointimal hyperplasia.

METHODS AND RESULTS

Yorkshire pigs randomly received either oral pemafibrate (30 mg/day; n=6) or control vehicle (n=7) for 7 days, followed by coronary arterial implantation of 3.5 × 12 mm bare metal stents (2–4 per animal; 44 stents total). On day 7, intracoronary molecular‐structural near‐infrared fluorescence and optical coherence tomography imaging was performed to assess the arterial inflammatory response, demonstrating that pemafibrate reduced stent‐induced inflammatory protease activity (near‐infrared fluorescence target‐to‐background ratio: pemafibrate, median [25th‐75th percentile]: 2.8 [2.5–3.3] versus control, 4.1 [3.3–4.3], P=0.02). At day 28, animals underwent repeat near‐infrared fluorescence–optical coherence tomography imaging and were euthanized, and coronary stent tissue molecular and histological analyses. Day 28 optical coherence tomography imaging showed that pemafibrate significantly reduced stent neointima volume (pemafibrate, 43.1 [33.7–54.1] mm³ versus control, 54.2 [41.2–81.1] mm³; P=0.03). In addition, pemafibrate suppressed day 28 stent‐induced cellular inflammation and neointima expression of the inflammatory mediators TNF‐α (tumor necrosis factor‐α) and MMP‐9 (matrix metalloproteinase 9) and enhanced the smooth muscle differentiation markers calponin and smoothelin. In vitro assays indicated that the STAT3 (signal transducer and activator of transcription 3)–myocardin axes mediated the inhibitory effects of pemafibrate on smooth muscle cell proliferation.

CONCLUSIONS

Pemafibrate reduces preclinical coronary stent inflammation and neointimal hyperplasia following bare metal stent deployment. These results motivate further trials evaluating pemafibrate as a new strategy to prevent clinical stent restenosis.

Mortality Rates After Paclitaxel-Coated Device Use in Patients With Occlusive Femoropopliteal Disease: An Updated Systematic Review and Meta-Analysis of Randomized Controlled Trials

PURPOSE

A late increased mortality risk has been reported in a summary level meta-analysis of patients with femoropopliteal artery occlusive disease treated with paclitaxel-coated angioplasty balloons and stents. However, at the longer follow up timepoints that analysis was limited by small trial numbers and few participants. The aim of this study was to report an updated summary level risk of all-cause mortality after treatment with paclitaxel-coated devices in that same patient group.

MATERIALS AND METHODS

We performed a systematic review and meta-analysis of randomized controlled trials to investigate the mortality outcomes associated with paclitaxel-coated devices used to treat patients with occlusive disease of femoropopliteal arteries (last search date December 10, 2020). The single primary endpoint was all-cause mortality.

RESULTS

We identified 34 randomized controlled trials (7654 patients; 84% intermittent claudication). There were 622 deaths among 4147 (15.0%) subjects in the paclitaxel device group and 475 deaths among 3507 (13.5%) subjects in the noncoated control group [relative risk ratio (RR) 1.07, 95% confidence interval (CI) 0.96 to 1.20, p=0.20, I²=0%). All-cause mortality was similar between groups at 12 months (34 studies, 7654 patients; RR 0.99, 95% CI 0.81 to 1.22, p=0.94, I²=0%), 24 months (20 studies, 3799 patients; RR 1.16, 95% CI 0.87 to 1.55, p=0.31, I²=0%), and 60 months (9 studies, 2288 patients; RR 1.19, 95% CI 0.98 to 1.45, p=0.08, I²=0%).

CONCLUSION

This updated meta-analysis with included additional trials and larger patient numbers shows no evidence of increased risk of all-cause mortality in patients treated with paclitaxel-coated devices, compared with uncoated devices for femoropopliteal disease at all time points to 60 months. There is therefore no justification to limit their use, or alter regulatory body follow-up recommendations in this patient population.

SYSTEMATIC REVIEW REGISTRATION

CRD42020216140.

Cilostazol: a Review of Basic Mechanisms and Clinical Uses

Primarily used in the treatment of intermittent claudication, cilostazol is a 2-oxyquinolone derivative that works through the inhibition of phosphodiesterase III and related increases in cyclic adenosine monophosphate (cAMP) levels. However, cilostazol has been implicated in a number of other basic pathways including the inhibition of adenosine reuptake, the inhibition of multidrug resistance protein 4, among others. It has been observed to exhibit antiplatelet, antiproliferative, vasodilatory, and ischemic-reperfusion protective properties. As such, cilostazol has been investigated for clinical use in a variety of settings including intermittent claudication, as an adjunctive for reduction of restenosis after coronary and peripheral endovascular interventions, and in the prevention of secondary stroke, although its widespread implementation for indications other than intermittent claudication has been limited by relatively modest effect sizes and lack of studies in western populations. In this review, we highlight the pleiotropic effects of cilostazol and the evidence for its clinical use.

Meta-Analysis Comparing Endovascular Treatment Modalities for Femoropopliteal Peripheral Artery Disease

Endovascular interventions are commonly utilized for treatment of femoropopliteal peripheral artery disease. The relative efficacy of these interventions remains unclear. A Bayesian network meta-analysis was performed comparing 5 endovascular treatment modalities: balloon angioplasty (BA), bare metal stent (BMS), covered stent (CS), drug-coated balloon (DCB), drug-eluting stent (DES) for femoropopliteal peripheral artery disease. The primary efficacy end points were freedom from target lesion revascularization (TLR) and primary patency at 12 months. BA was the reference treatment. Twenty-two trials including 4,381 participants provided data on TLR. Sixteen trials including 3,691 participants provided data on primary patency. Point estimates for DCB suggested that it was the most efficacious treatment for freedom from TLR (odds ratio [OR] 4.23; 95% credible intervals [CrI] 2.43 to 7.66) followed by CS (OR 3.65; 95% CrI 1.11 to 12.55), DES (OR 2.64; 95% CrI 0.72 to 9.77), and BMS (OR 2.3; 95% CrI 1.11 to 4.76). Similarly, point estimates for primary patency were highest with DES (OR 8.93; 95% CrI 3.04, 27.14) followed by CS (OR 3.91; 95% CrI 1.18, 13.84), DCB (OR 3.32; 95% CrI 1.8, 6.25), and BMS (OR 3.5; 95% CrI 1.58, 7.99). In conclusion, DCB has the lowest need for TLR whereas DES has the highest primary patency rate. DCB, CS, and BMS were associated with significant reductions in TLR compared with BA, whereas DCB, DES, CS, and BMS were associated with significantly improved primary patency compared with BA.

Mortality in patients undergoing revascularization with paclitaxel eluting devices for infrainguinal peripheral artery disease: Insights from a network meta-analysis of randomized trials

OBJECTIVES

We aimed to evaluate whether paclitaxel eluting devices increased the risk of death in patients undergoing revascularization for infrainguinal peripheral artery disease using network meta-analyses.

METHODS

PUBMED and EMBASE were searched through April 2020 for randomized trials in patients with infrainguinal peripheral artery disease who underwent revascularization with or without a paclitaxel eluting device (balloon/stent). Short-term mortality defined as death at 6-12 months, and long-term mortality defined as death at >12 months after revascularization.

RESULTS

Our search identified 57 eligible randomized controlled studies enrolling a total of 9,362 patients comparing seven revascularization strategies (balloon angioplasty vs. bare metal stent vs. covered stent vs. paclitaxel eluting stent vs. other drug eluting stent vs. paclitaxel-coated balloon vs. bypass surgery). Overall, paclitaxel eluting stent and paclitaxel-coated balloons did not increase short-term mortality (eg, vs. balloon angioplasty: paclitaxel-coated balloon OR [95% CI] 1.21 [0.88-1.66], p = .24; paclitaxel eluting stent OR [95%CI] 1.01 [0.63-1.63], p = .97, respectively). In addition, paclitaxel eluting stent did not show significant increase in long-term mortality (eg, vs. balloon angioplasty: OR [95%CI] 1.06 [0.70-1.59], p = .79). However, paclitaxel-coated balloon showed significant increase in long-term mortality compared to balloon angioplasty and bypass (vs. balloon angioplasty: OR [95% CI] 1.48 [1.06-2.07], p = .021; vs. bypass: OR [95%CI] 1.73 [1.05-2.84], p = .031, respectively).

CONCLUSIONS

In this meta-analysis of randomized trials, there was no significant increase in mortality with paclitaxel eluting stent, but there was increased risk of long-term mortality in paclitaxel-coated balloon for the treatment of infrainguinal peripheral artery disease.

Antiplatelet and Anticoagulant Use in Randomised Trials of Patients Undergoing Endovascular Intervention for Peripheral Arterial Disease: Systematic Review and Narrative Synthesis

OBJECTIVE

Randomised trials of new devices for peripheral arterial endovascular intervention are published regularly. The evidence for which antiplatelet and/or anticoagulant (antithrombotic) therapy to use after an intervention is lacking. The aim of this systematic review was to examine the antithrombotic regimens in randomised trials for peripheral arterial endovascular intervention to understand choices made and trends with time or type of device.

METHODS

Data sources were the Medline, Embase, and Cochrane Library databases. Randomised trials including participants with peripheral arterial disease undergoing any endovascular arterial intervention were included. Trial methods were assessed to determine whether an antithrombotic protocol had been specified, its completeness, and the agent(s) prescribed. Antithrombotic therapy protocols were classed as peri-procedural (preceding and during intervention), immediate post-procedural (up to 30 days following intervention), and maintenance post-procedural (therapy continuing beyond 30 days).

RESULTS

Ninety-four trials were included in narrative synthesis. Study quality was low. None of the trials justified their antithrombotic therapy protocol. Only 29% of trials had complete peri-procedural antithrombotic protocols, and 34% had complete post-procedural protocols. In total, 64 different peri-procedural protocols, and 51 separate post-procedural protocols were specified. Antiplatelet monotherapy and unfractionated heparin were the most common regimen choices in the peri-procedural setting, and dual antiplatelet therapy (55%) was most commonly utilised post procedure. Over time there has been an increasing tendency to use dual therapy (p < .001). This corresponds with the introduction of newer technologies and trials focussed on below knee intervention.

CONCLUSION

Randomised trials comparing different types of peripheral endovascular arterial intervention have a high level of heterogeneity in their antithrombotic regimens. Antiplatelet therapy needs to be standardised in trials comparing endovascular technologies to reduce potential confounding. To do this, an independent randomised trial specifically examining antiplatelet therapy following peripheral arterial endovascular intervention is needed.

Angioplasty or bare metal stent versus drug-eluting endovascular treatment in femoropopliteal artery disease: a systematic review and meta-analysis

INTRODUCTION

Endovascular treatment represents nowadays the preferred therapeutic approach for disabling femoro-popliteal arterial occlusive disease in fit patients. In the latest years, in order to improve short- and long-term outcomes, drug eluting devices have been developed. Drug coated balloons (DCB) and drug eluting stents (DES) are today employed in clinical practice, and several studies has been completed to assess their performance in different clinical scenarios. Objective of the present review and meta-analysis is to compare clinical results of different endovascular treatment modalities in the published literature in the last 10 years.

EVIDENCE ACQUISITION

A systematic review and meta-analysis following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement on the literature regarding direct comparisons between DCB, DES, bare metal stents (BMS) and Plain Old Balloon Angioplasty (POBA) has been conducted. Primary outcomes were considered Primary Patency and Target Lesion Revascularization (TLR) at 12 months. Analysis of late survival in different treatment groups was outside the scope of the present study and was therefore not included as main end point.

EVIDENCE SYNTHESIS

Meta analysis results confirm that DCB outperforms POBA in both primary patency (estimate OR=3.17, 95% CI: 2.10-4.76) and TLR (POBA estimate OR=3.59, 95% CI= 2.31-5.56). No clear evidences emerged comparing DES and BMS; however, DES were shown to fare better than BMS in terms of TLR when analyzing lesions <15 cm (OR 0.36, 95% CI: 0.35-0.36). Comparison of DCB and DES revealed higher rates of TLR for DES (OR 1.26 95% CI: 1.07-1.49), however no significant differences have been found regarding primary patency analyzing such long lesions (range 14-19.4 cm) as those included in the studies.

CONCLUSIONS

While confirming that DCB outperforms POBA in terms of primary patency and TLR at 12 months, only TLR benefits are noted for DES vs. BMS and DCB vs. DES in limited clinical settings. Further RCTs are needed to strongly assess the compared performance of drug eluting devices in relation to lesion length and controlling possible confounders.

Cilostazol inhibits hyperglucose-induced vascular smooth muscle cell dysfunction by modulating the RAGE/ERK/NF-κB signaling pathways

Background

Increasing evidence suggests that high glucose (HG) causes abnormalities in endothelial and vascular smooth muscle cell function (VSMC) and contributes to atherosclerosis. Receptor for advanced glycation end-products (RAGE) has been linked to the pathogenesis of both the macrovascular and microvascular complications of diabetes. Cilostazol is used to treat diabetic vasculopathy by ameliorating HG-induced vascular dysfunction.

Objectives

In this study, we investigated whether the cilostazol suppression of HG-induced VSMC dysfunction is through RAGE signaling and its possible regulation mechanism.

Method

We investigated the effect of HG and cilostazol on RAGE signaling in A7r5 rat VSMCs. Aortic tissues of streptozotocin (STZ) diabetic mice were also collected.

Results

Aortic tissue samples from the diabetic mice exhibited a significantly decreased RAGE expression after cilostazol treatment. HG increased RAGE, focal adhesion kinase (FAK), matrix metalloproteinase-2 (MMP-2), intercellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expressions, and was accompanied with increased reactive oxygen species (ROS), cell proliferation, adhesion and migration. Cilostazol significantly reversed HG-induced RAGE, ROS, downstream gene expressions and cell functions. RAGE knockdown significantly reversed the expressions of HG-induced vasculopathy related gene expressions and cell functions. Cilostazol with RAGE knockdown had additive effects on downstream ERK/NF-κB signaling pathways, gene expressions and cell functions of A7r5 rat VSMCs in HG culture.

Conclusions

Both in vitro and in vivo experimental diabetes models showed novel signal transduction of cilostazol-mediated protection against HG-related VSMC dysfunction, and highlighted the involvement of RAGE signaling and downstream pathways.

Vessel Calcification as a Risk Factor for In-Stent Restenosis in Complex Femoropopliteal Lesions After Zilver PTX Paclitaxel-Coated Stent Placement

Purpose: To evaluate the effect of vessel calcification on in-stent restenosis (ISR) after drug-coated stent (DCS) placement in the femoropopliteal segment. Materials and Methods: A retrospective multicenter study was undertaken involving 220 consecutive symptomatic patients (mean age 73.1±8.3 years; 175 men) with femoropopliteal lesions in 230 limbs treated with the Zilver PTX DCS and having duplex surveillance after the endovascular procedures. Mean lesion length was 16.4±9.8 cm (range 2–40); there were 104 (45.2%) total occlusions and 68 (29.6%) in-stent restenoses (ISR). Twenty (8.7%) vessels had no runoff. The majority of lesions (148, 64.3%) were calcified according to the peripheral arterial calcium scoring system (PACSS). Primary patency was evaluated by duplex. Lesions were classified as either PACSS 0–2 (none or unilateral wall calcification) or PACSS 3 and 4 (bilateral wall calcification). Multivariate analysis was performed to identify variables associated with ISR; the results are given as the hazard ratio (HR) and 95% confidence interval (CI). Results: The 1-, 2-, and 5-year primary patency and freedom from clinically-driven target lesion revascularization estimates were 75.9%, 63.6%, and 45.0%, and 84.7%, 73.7%, and 54.2%, respectively. Major amputations were performed on 4 limbs during follow-up. In multivariate analysis, vessel calcification (adjusted HR 1.718, 95% CI 1.035 to 2.851, p=0.036) was significantly correlated with the occurrence of ISR, along with lesion length (adjusted HR 1.041, 95% CI 1.013 to 1.070, p=0.003), and cilostazol administration (adjusted HR 0.476, 95% CI 0.259 to 0.876, p=0.017). Conclusion: This study suggested that bilateral vessel wall calcification was an independent risk factor for ISR in complex femoropopliteal lesions after Zilver PTX DCS placement, along with lesion length; cilostazol administration had a protective effect.

Restenosis Prevention With Drug Eluting or Covered Stents in Femoropopliteal Arterial Occlusive Disease: Evidence From a Comprehensive Network Meta-analysis

BACKGROUND/OBJECTIVE

Endovascular interventions for femoropopliteal (FP) arterial diseases are limited by the development of restenosis. Current drug coated devices are capable of preventing restenosis by releasing antiproliferative agents to the vessel wall. However, default strategies for the treatment of FP diseases remain controversial. The aim of this study was to investigate the efficacy differences between drug eluting stents (DES), covered stents (CS), and other commonly used endovascular treatments in FP lesions, including drug coated balloons (DCBs), bare metal stents (BMS), and percutaneous transluminal angioplasty (PTA).

METHODS

A comprehensive network meta-analysis was conducted using data from relevant randomised control trials published up to 16 December 2018. Primary patency and target lesion revascularisation (TLR) at 12 months were set as the primary and secondary end points, respectively.

RESULTS

Twenty-eight eligible trials including 4728 patients were selected. DES was ranked as the most effective treatment in the multidimensional analysis of primary patency; however, there was no significant difference in the efficacy of DES and that of CS, DCB, and BMS. However, in short lesions (<10 cm), DES was significantly more effective than DCB (odds ratio 0.35; 95% confidence interval 0.15-0.83). Primary patency at 12 months was significantly lower with PTA. In terms of preventing TLR, DCB was ranked first, followed by DES, CS, BMS, and PTA. TLR was significantly higher with PTA than with other treatment strategies.

CONCLUSION

The findings of this network meta-analysis suggest that this is not the appropriate time to identify the best endovascular treatment strategy for the FP segment. DES is effective in maintaining mid-term patency, especially in short lesions, whereas DCB seems more suitable for clinical use.

Outcomes with cilostazol after endovascular therapy of peripheral artery disease

The role of cilostazol after endovascular therapy (EVT) of peripheral artery disease (PAD) remains unclear. We conducted a meta-analysis for all studies reporting the outcomes of cilostazol after EVT of PAD from January 2000 through November 2018 with the outcomes of interest including primary patency, major adverse limb events (MALE), target lesion revascularization (TLR), and major amputation. We included eight studies (three randomized controlled trials (RCTs) and five observational studies) with a total of 3846 patients (4713 lesions). During a mean follow-up duration of 12.5 ± 5 months, the use of cilostazol was associated with higher primary patency (OR 2.28, 95% CI (1.77, 2.94), p < 0.001, I² = 24%), lower risk of TLR (OR 0.37, 95% CI (0.26, 0.52), p < 0.001, I² = 0%), and lower risk of major amputation (OR 0.15, 95% CI (0.04, 0.62), p = 0.008, I² = 0%). The use of cilostazol in RCTs was associated with significantly higher odds of primary patency compared with observational studies (OR 3.37 vs 2.28, p-interaction = 0.03). After further subgroup analysis, cilostazol remained associated with higher primary patency regardless of the use of anticoagulants (warfarin) (p-interaction = 0.49). We conclude that the use of cilostazol after EVT of femoropopliteal and iliac lesions is associated with improved primary patency and lower risk of major amputation and TLR. The favorable impact of cilostazol is independent of the use of warfarin. PROSPERO identifier: CRD42018092715.

Risk of Death Following Application of Paclitaxel-Coated Balloons and Stents in the Femoropopliteal Artery of the Leg: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background Several randomized controlled trials ( RCT s) have already shown that paclitaxel-coated balloons and stents significantly reduce the rates of vessel restenosis and target lesion revascularization after lower extremity interventions. Methods and Results A systematic review and meta-analysis of RCT s investigating paclitaxel-coated devices in the femoral and/or popliteal arteries was performed. The primary safety measure was all-cause patient death. Risk ratios and risk differences were pooled with a random effects model. In all, 28 RCT s with 4663 patients (89% intermittent claudication) were analyzed. All-cause patient death at 1 year (28 RCT s with 4432 cases) was similar between paclitaxel-coated devices and control arms (2.3% versus 2.3% crude risk of death; risk ratio, 1.08; 95% CI, 0.72-1.61). All-cause death at 2 years (12 RCT s with 2316 cases) was significantly increased in the case of paclitaxel versus control (7.2% versus 3.8% crude risk of death; risk ratio, 1.68; 95% CI, 1.15-2.47; -number-needed-to-harm, 29 patients [95% CI , 19-59]). All-cause death up to 5 years (3 RCT s with 863 cases) increased further in the case of paclitaxel (14.7% versus 8.1% crude risk of death; risk ratio, 1.93; 95% CI , 1.27-2.93; -number-needed-to-harm, 14 patients [95% CI , 9-32]). Meta-regression showed a significant relationship between exposure to paclitaxel (dose-time product) and absolute risk of death (0.4±0.1% excess risk of death per paclitaxel mg-year; P<0.001). Trial sequential analysis excluded false-positive findings with 99% certainty (2-sided α, 1.0%). Conclusions There is increased risk of death following application of paclitaxel-coated balloons and stents in the femoropopliteal artery of the lower limbs. Further investigations are urgently warranted. Clinical Trial Registration URL : www.crd.york.ac.uk/PROSPERO . Unique identifier: CRD 42018099447.