Selective stenting in subintimal angioplasty: Analysis of primary stent outcomes

Percutaneous Intentional Extraluminal Recanalization of Chronic Total Occlusions: A Review of Reentry Devices

Percutaneous intentional extraluminal recanalization (PIER) is an endovascular subintimal crossing technique used to treat chronic total occlusions (CTOs) of the peripheral arteries. Intraluminal revascularization remains the standard over PIER when technically feasible; however, when intraluminal approaches fail, PIER may be preferred prior to pursuit of surgical bypass grafting. The major cause of failure of PIER is inability to reenter the true lumen after crossing the CTO. Therefore, several reentry devices and endovascular techniques have been developed to allow for the operators to safely and quickly access the true lumen distal to the occlusion. Reentry devices currently available on the market include the Pioneer Plus catheter, Outback Elite catheter, OffRoad catheter, Enteer catheter, and GoBack catheter. These devices have unique methods of use and specific advantages with regard to their technical success along with reduced procedural and fluoroscopic time. In addition, there are other endovascular techniques available that may facilitate true lumen reentry and these will also be reviewed.

Differential efficacy between stenting and plain balloon angioplasty for femoropopliteal disease with or without total occlusion

BACKGROUND/AIMS

Whether the presence of chronic total occlusion (CTO) affects patency after stenting in femoropopliteal lesions is unknown. We determined the effects of plain balloon angioplasty (POBA) in comparison with those of stenting on patency for femoropopliteal CTO and stenosis (non-CTO).

METHODS

We analyzed data from the Korean Vascular Intervention Society Endovascular Therapy in Lower-Limb Artery Diseases Registry, a multicenter cohort of patients with lower extremity peripheral arterial disease. Data from 1,329 patients and 1558 limbs treated with endovascular intervention for at least one femoropopliteal lesion were evaluated.

RESULTS

Among the 1,558 limbs, 345, 432, 275, and 506 were in the non-CTO-POBA, non-CTO-stent, CTO-POBA, and CTO-stent groups, respectively. During follow-up, loss of clinical primary patency, a composite of freedom from restenosis or clinically driven target lesion revascularization, occurred in 65 (18.8%), 68 (15.7%), 62 (22.5%), and 113 limbs (22.3%) in the non-CTO-POBA, non-CTO-stent, CTO-POBA, and CTO-stent groups, respectively. The patients in the non-CTO-stent group showed a significantly better clinical primary patency than those in the no-CTO-POBA group, whereas those in the CTO-stent and CTO-POBA groups showed no significant differences. After inverse probability of treatment weighting to balance the differences among covariates between the non-CTO-stent and non-CTO-POBA groups, the non-CTO-stent group still showed superior clinical primary patency as compared with the non-CTO-POBA group.

CONCLUSION

In the patients with femoropopliteal stenosis without CTO, stenting resulted in better clinical outcomes than balloon angioplasty. The presence of CTO in the femoropopliteal lesion should be considered when selecting a suitable device for performing endovascular procedures.

Long-Term Clinical Outcomes of Percutaneous Transluminal Angioplasty with Optional Stenting in Patients with Superficial Femoral Artery Disease: A Retrospective, Observational Analysis

BACKGROUND AND OBJECTIVE

The recent ESC guideline advises primary stent placement in superficial femoral arterial disease (SFAD). The aim of this study was to compare clinical outcomes of SFAD patients selected for stent placement with plain percutaneous transluminal angioplasty (PTA).

MATERIALS AND METHODS

A single centre retrospective, observational analysis was performed of all consecutive patients undergoing endovascular treatment for SFAD from 2004 to 2015. Primary endpoints were primary and secondary clinical patency rates in patients with or without stent placement. Secondary endpoints were recurrence rates and number of amputations. Kaplan-Meier curves were used to compare patency rates. Multivariable Cox regression analysis was performed to adjust for confounding variables and to identify variables associated with loss of patency.

RESULTS

A total of 389 patients were analysed with a median follow up of 42 months. Two hundred and fifty one patients (64.5%) were stented. Primary clinical patency rates at 1, 3, and 5 years were 82.8%, 71.0%, and 65.6% after PTA and 76.3%, 65.7%, and 58.1% after stent placement (PTA-S), respectively (p = .30). Secondary patency rates were also comparable for the PTA and PTA-S group resulting in 1, 3 and 5 year clinical secondary patency of 89.1%, 81.0%, and 76.3% in the PTA group versus 87.8%, 78.5%, and 71.9% in the PTA-S group (p = .58). Multivariable analysis revealed equal primary and secondary clinical patency between the treatment groups. The absolute re-intervention rate was 29.3%. The number of re-interventions and amputation rate did not significantly differ between the two groups (p = .41 and p = .75).

CONCLUSIONS

Selective stenting in patients with SFAD shows comparable results in long-term clinical outcomes in patients who were treated with plain PTA as well as patients who are selected for stent placement. An approach of selective stenting is justified.

SFA Intervention: Intraluminal or Subintimal?

Subintimal angioplasty (SA) is an endovascular technique to recanalize an occluded arterial segment through an extraluminal channel between the intima and media. Since its introduction in 1989, the technical success rate has improved with the accumulation of procedural experience and the development of retrograde approaches and re-entry devices. To date, no randomized trial has compared SA with intraluminal angioplasty (IA) for chronic total occlusion (CTO) of the superficial femoral artery (SFA). Based on limited data from several registry studies, SA appears to achieve a higher technical success rate than IA, whereas mid-term primary patency rates are comparable for both endovascular wiring strategies for SFA CTO. Additional clinical data are needed to confirm that SA is as effective as IA. The optimal stenting strategy and role of drug-eluting technologies also need to be defined to improve SA outcomes.

Effects of tripterygium glycosides on restenosis following endovascular treatment

The mechanism and associated factors of restenosis following intravascular stent implantation remain to be elucidated. The present two‑part experimental and clinical study aimed to investigate the effects of tripterygium glycosides on in‑stent restenosis subsequent to intra‑arterial therapy. Following endovascular stent implantation in rabbit iliac arteries, post‑stent outcomes were evaluated in cyclosporine groups, low‑dose and high‑dose tripterygium glycosides groups and controls. Post‑operative angiography indicated that vessel diameters were similar between groups; however, at 28 days after receiving the therapeutic agents, vessels of the cyclosporine and tripterygium glycosides groups were significantly larger than those of the controls. Furthermore, three groups of patients had comparable baseline levels of interleukin (IL)‑10, IL‑18 and C‑reactive protein, and intima‑media thickness. However, 1 month after stent implantation, levels of IL‑10 and IL‑18 were markedly reduced in the high‑ and low‑dose tripterygium glycosides groups compared with controls. At 6 months after surgery, the stent patency rate in patients with bare stents was significantly lower than in patients receiving tripterygium glycosides (P≤0.009). In addition, the ankle‑brachial index was also higher than in those without tripterygium glycosides (P<0.001). Results of the experimental and clinical studies suggest that tripterygium glycosides may inhibit and possibly aid in the prevention of in‑stent restenosis formation following endovascular treatment of lower‑extremity artery disease.

Technical and early outcomes using ultrasound-guided reentry for chronic total occlusions

BACKGROUND

Subintimal angioplasty is a common treatment for chronic total occlusions (CTOs) in the iliac and infrainguinal arteries. Although technical success has been described using intravascular ultrasound-guided reentry devices (IVUS-RED), outcomes are still not well defined. This report describes the technical aspects and longitudinal follow-up after intravascular ultrasound-guided reentry of iliac and infrainguinal CTOs.

METHODS

A retrospective review was performed of 20 patients with lower extremity CTO treated with IVUS-RED from 2011 to 2013. A matched cohort of patients who underwent lower extremity interventions without the use of IVUS-RED was also identified. Procedural success, patency estimates, ankle-brachial indices (ABIs), complications, and limb salvage were analyzed.

RESULTS

Twenty patients (mean age, 69 ± 13 years), including 11 men and 9 women, underwent attempted IVUS-RED-guided recanalization. Median follow-up was 4.3 months (range, 0.4-24). Eleven patients presented with critical limb ischemia (CLI), and 9 presented with claudication. Technical success was achieved in 18 (90%) patients. Ten common iliac arteries, 3 external iliac arteries, and 5 superficial femoral arteries (SFA) were treated. No intraoperative complications resulted from device use. After procedure, ABIs significantly increased (0.5-0.9; P < 0.01) in the 13 patients with follow-up. Primary patency for the entire cohort was 62% at 12 months. No patient treated for claudication required reintervention, whereas 3 (27%) of those treated for CLI required repeat interventions. During follow-up, 2 patients died unrelated to the procedure, 1 patient required an amputation, and 1 patient eventually required open revascularization. When the IVUS-RED group was compared with a cohort matched on Trans-Atlantic Inter-Society Consensus and age, no difference was found in runoff scores and patency between the 2 groups during follow-up (P > 0.05).

CONCLUSIONS

Recanalization of CTO using IVUS-RED is safe and effective. Use of IVUS-RED does not adversely impact outcomes in conjunction with other endovascular techniques. Early follow-up demonstrates acceptable patency, especially in patients with claudication, and freedom from reintervention.

Optimal management of infrainguinal arterial occlusive disease

Peripheral arterial occlusive disease is becoming a major health problem in Western societies as the population continues to age. In addition to risk of limb loss, the complexity of the disease is magnified by its intimate association with medical comorbidity, especially cardiovascular and cerebrovascular disease. Risk factor modification and antiplatelet therapy are essential to improve long-term survival. Surgical intervention is indicated for intermittent claudication when a patient’s quality of life remains unacceptable after a trial of conservative therapy. Open reconstruction and endovascular revascularization are cornerstone for limb salvage in patients with critical limb ischemia. Recent advances in catheter-based technology have made endovascular intervention the preferred treatment approach for infrainguinal disease in many cases. Nevertheless, lower extremity bypass remains an important treatment strategy, especially for reasonable risk patients with a suitable bypass conduit. In this review, we present a summary of current knowledge about peripheral arterial disease followed by a review of current, evidence-based medical and surgical therapy for infrainguinal arterial occlusive disease.

Subintimal recanalization of occluded stents: the substent technique

PURPOSE

Application of metal stents is complicated by neointimal hyperplasia leading to vessel restenosis and reocclusion. Treatment options in cases presenting with complete occlusion of the stented segment and recurrent critical limb ischemia (CLI) are limited. We present the option of the subintimal/substent technique in dealing with occluded stents.

METHODS

The study included patients presenting with recurrent CLI due to impaired blood flow as a result of complete occlusion of previously inserted metal stents and unsuccessful intraluminal crossing of the lesion via either the antegrade or retrograde approach. In these cases, crossing the occlusion through the subintimal/substent plane was attempted. Primary end points included technical success, safety of the procedure, clinical improvement, and limb salvage, while secondary end points were patient survival, primary patency, and vessel restenosis rates at 1-year follow-up. Study end points were calculated by Kaplan-Meier survival analysis.

RESULTS

Between July 2006 and October 2011, a total of 14 patients (mean age 69.14 ± 12.59 years, 12 men) were treated with the substent technique and included in the analysis. Technical success rate was 85.71% (12 of 14), with a total lesion length of 193.57 ± 90.78 mm. The mean occluded stented segment length was 90.21 ± 44.34 mm. In 10 (83.33%) of 12 cases, a new stent had to be placed by the side of the old occluded one, while the remaining two cases (16.67%) were treated only with balloon angioplasty. No serious adverse events were noted during the immediate postprocedural period. All successfully treated patients improved clinically. Estimated limb salvage was 90.9%, and patient survival rate was 90.0% at 1 year's follow-up. Primary patency was 45.50% and vessel restenosis 77.30%.

CONCLUSION

Subintimal recanalization of occluded metal stents through the substent plane is a valuable alternative treatment option, especially in patients with recurrent CLI with few alternatives.

Current treatment methods for long occlusions of the femoropopliteal segment in patients with intermittent claudication: Minireview

Backround. Intermittent claudication is a classic symptom of peripheral arterial disease. It is mainly treated conservatively but if this fails, a form of revascularization is indicated. The revascularization in chronic occlusion of femoropopliteal region is currently performed by two basic methods: the standard method of surgical bypass and the newer miniinvasive alternative represented by the endovascular method. The treatment of patients with solely claudication and long occlusion of femoropopliteal region remains controversial. The aim of this minireview was to determine whether surgical bypass is still the best method of choice in a time of endovascular techniques.

METHODS

A MEDLINE search for original and review articles using key terms, intermittent claudication and long femoropopliteal oclusion.

RESULTS AND CONCLUSION

No ideal treatment for long occlusions of the femoropopliteal segment has been established to date. It is clear that the role of endovascular techniques in the treatment of SFA occlusions is increasing. It remains that, lower risk patients with claudication should be examined to assess the quality of veins suitable for revascularization and bypass should be selected as the first method of choice.

Subintimal angioplasty of long chronic total femoropopliteal occlusions: long-term outcomes, predictors of angiographic restenosis, and role of stenting

PURPOSE

The purpose of this article is to report the results of a prospective single-center study analyzing the long-term clinical and angiographic outcomes of subintimal angioplasty (SIA) for the treatment of chronic total occlusions (CTOs) of the femoropopliteal artery.

MATERIALS AND METHODS

Patients with severe intermittent claudication or critical limb ischemia (CLI) were enrolled in the study. All lesions were treated with SIA and provisional stenting. Primary end points were technical success, patient survival, limb salvage, lesion primary patency, angiographic binary restenosis (>50%), and target lesion revascularization (TLR). Regular clinical and angiographic follow-up was set at 6 and 12 months and yearly thereafter. Study end points were calculated with life-table survival analysis. Proportional-hazards regression analysis with a Cox-model was applied to adjust for confounding factors of heterogeneity.

RESULTS

Between May 2004 and July 2009, 98 patients (105 limbs, patient age 69.3±9.9 years) were included in the study. Technical success rate was 91.4% with a lesion length of 121±77 mm. Limb-salvage and survival rates were 88.7% and 84.1% at 3 years, respectively. After 12, 24, and 36 months, primary patency was 80.1%, 42.3%, and 29.0%, angiographic binary restenosis was 37.2%, 68.6%, and 80.0%, and TLR was 84.8%, 73.0%, and 64.5%, respectively. CLI was the only adverse predictor for decreased primary patency (hazard ratio [HR] 0.36; 95% confidence interval [CI] 0.16-0.80, p=0.012), whereas significantly less restenosis was detected after spot stenting of the entry and/or re-entry site (HR 0.31; 95% CI 0.10-0.89, p=0.01 and HR 0.20; 95% CI 0.07-0.56, p=0.002, respectively).

CONCLUSIONS

Subintimal angioplasty is a safe and effective revascularization technique for the treatment of CTOs of the femoropopliteal artery. Provisional stenting may have a role at the subintimal entry or true lumen re-entry site.

Efficacy of endoluminal interventional therapy in diabetic peripheral arterial occlusive disease: a retrospective trial

Background

The purpose of this study was to assess the efficacy of interventional therapy for peripheral arterial occlusive disease and the difference between diabetic patients and non-diabetic patients.

Methods

139 consecutive patients between September 2006 and September 2010 who underwent percutaneous lower extremity revascularization for arterial lesions were divided into diabetes group (n = 62) and non-diabetes group (n = 77). Before intervention, rest ankle brachial indexes and three dimensional computed tomography angiography from abdominal aorta to tiptoe were performed. The interventional treatments included angioplasty with or without stenting. The clinical outcomes included rest ankle-brachial indexes, primary patency rates, secondary patency rates and limb-salvage rates for 6-month, 12-month, 24-month and 36-month after treatment. The primary and secondary patency rates of all interventions and the limb-salvage rates of the patients are illustrated by Kaplan-Meier curves and compared by log-rank analysis.

Results

The interventional operation success rates were 98.4% (61/62) in diabetes group and 100% (77/77) in non-diabetes group. The re-interventional operation success rates were 85.7% (18/21) in diabetes group and 76.9% (20/26) in non-diabetes group. The mean value of ankle brachial indexes was significantly increased after intervention (0.397 ± 0.125 versus 0.779 ± 0.137, t = -25.780, P < 0.001) in diabetes group and (0.406 ± 0.101 versus 0.786 ± 0.121, t = -37.221, P < 0.001) in non-diabetes group. Perioperative 30-day mortality was 0%. Major complications included groin hematoma in 7.2%, and pseudoaneurysm formation 2.2%. In diabetes group, 6, 12, 24, and 36-month primary patency rates were 88.7% ± 4.0%, 62.3% ± 6.6%, 55.3% ± 7.0%, and 46.5% ± 7.5%; secondary patency rates were 93.5% ± 3.1%, 82.3% ± 5.1%, 70.8% ± 6.5%, and 65.7% ± 7%; limb-salvage rates were 95.2% ± 2.7%, 87.7% ± 4.4%, 85.5% ± 4.8%, and 81.9% ± 5.8%. In non-diabetes group, 6, 12, 24, and 36-month primary patency rates were 90.9% ± 3.3%, 71.8% ± 5.4%, 71.8% ± 5.4%, and 60.9% ± 6.2%; secondary patency rates were 96.1% ± 2.2%, 91.6% ± 3.3%, 82.7% ± 4.8%, and 71.8% ± 6.2%; limb-salvage rates were 97.4% ± 1.8%, 94.4% ± 2.7%, 90.6% ± 3.7%, and 83.1% ± 5.4%. The differences between two groups were not significant (P > 0.05).

Conclusion

With a low risk of morbidity and mortality, the percutaneous revascularization accepted by patients does not affect ultimate necessary surgical revascularization and consequently should be considered as the preferred therapy for chronic lower extremity ischemia. The efficacy and prognosis of interventional therapy in diabetic patients is similar that in non-diabetic patients.

Results With Viabahn-Assisted Subintimal Recanalization for TASC C and TASC D Superficial Femoral Artery Occlusive Disease

Objectives: Many investigators including TransAtlantic Inter-Society Consensus (TASC) recommend against primary endovascular treatment for severe (TASC C and D) superficial femoral artery (SFA) disease. Vein bypass is preferable but may not be appropriate due to comorbidities or lack of suitable vein. This study reviews our results with Viabahn stent graft-assisted subintimal recanalization (VASIR) for TASC C and D SFA atherosclerosis. Methods: In all, 13 males and 14 females, mean age 72 ± 11 years underwent 28 VASIR for severe (TASC C 8 of 28, TASC D 20 of 28, and 5 of 28 no continuous infrapopliteal runoff artery) SFA disease. Indications were claudication (14 of 28 limbs), ischemic rest pain (6 of 28), and tissue loss (8 of 28). Viabahn stent graft-assisted subintimal recanalization was chosen instead of bypass due to comorbidities or lack of vein. Patients received aspirin and, if not already taking warfarin, they also received clopidogrel. Patients were examined with Ankle-brachial Index (ABI) and duplex scan at 1 month, then every 3 months after VASIR. Results Viabahn stent graft-assisted subintimal recanalization was technically successful in all. Ankle-brachial Index averaged 0.47 ± 0.17 preprocedure, 0.89 ± 0.20 postprocedure, and increased by 0.15 or more in every case. Median follow-up is 20 months. There were 3 perioperative (<30 days) and 7 later failures including revision prior to any thrombosis. One patient required amputation. Four have died, 2 with patent grafts, none from causes related to VASIR, all more than 30 days post-VASIR. Estimated 1-year primary and secondary patency were 70% ± 11% and 73% ± 10%. Failure was not significantly associated with indications, comorbidities, or runoff status. There was a clear distinction between patients with early failure and the rest of the patients. None of the 8 patients with failure in the first 8 months after surgery has a patent graft. However, of 17 grafts primarily patent at 8 months, only 2 have failed (1 thrombosed and 1 required preemptive balloon angioplasty). There was a strong trend toward better patency with 6 and 7 mm diameter compared to 5 mm diameter stent grafts. Furthermore, although warfarin was not prescribed as part of the protocol, no patient taking warfarin before and who resumed warfarin after VASIR (n = 4) suffered failure. Conclusions: Despite significant early failures, we found VASIR to be durable in those who did not have early failure. Viabahn stent graft-assisted subintimal recanalization is an acceptable alternative to vein bypass in selected patients with severe SFA disease. Smaller arterial or stent graft diameter may be associated with poorer results. Warfarin may be valuable to reduce the risk of failure after VASIR.

Role of superficial femoral artery stents in the management of arterial occlusive disease: review of current evidence

The objectives of this study were to compare the 1-year patency of superficial femoral artery (SFA) stent placement with percutaneous transluminal angioplasty (PTA) alone and to attempt to define the role of stents in arterial occlusive disease. Literature searches of the Embase, Medline, and Cochrane databases identified relevant articles, which were split into two subgroups: those containing case-controlled matches for stenting and PTA and those considering only stent placement. The review conformed to the QUORUM statement. One-year patency rates were 219 of 383 (57%) in the stented group and 319 of 607 (53%) in the PTA group for matched cases (odds ratio 1.206 [95% CI 0.932-1.559; p = .115]). The patency of stents deployed secondarily was 554 of 909 (61%). The combined 1-year patency of primary and secondary SFA stents for matched and unmatched case series was 816 of 1,282 (64%). One-year patency rates following stent placement or PTA alone in well-matched patient groups demonstrated no significant difference. This would suggest that the routine use of primary SFA stenting should be undertaken only in selected cases and should mainly be used in "bailout" situations or for complex lesions where surgery is precluded. However, the studies used displayed a high degree of heterogeneity, and some used stent technology that is now considered obsolete. Ongoing randomized controlled trials will provide a more definitive answer to this important problem.

Subintimal angioplasty with the aid of a re-entry device for TASC C and D lesions of the SFA

AIM

The aim of this prospective study was to assess the clinical effectiveness and related midterm patency of subintimal angioplasty (SAP) in patients suffering from critical limb ischaemia (CLI) in a single tertiary care university centre. The secondary aim was to evaluate the safety and clinical effectiveness of using a re-entry device when re-canalisation by SAP was unsuccessful.

METHODS

From January 2005 to December 2007, consecutive patients suffering from CLI (Rutherford clinical categories: 4-6) were treated with SAP. All patients included in the study had occluded SFA (TASC C and D) and underwent clinical and ultrasound follow-up examinations at day 30 and at 3, 6, 9 and 12 months, and then yearly. A re-entry device (Outback, Cordis Corporation, Miami Lakes, Florida, USA in all cases) was only used when re-canalisation by simple SAP was unsuccessful, and stenting was used when residual stenosis was >30% or there was a flow-limiting dissection. Factors that could modify the outcome were analysed.

RESULTS

In this study, 145 patients were treated, with a technical success rate of 83.5% (121 of 145) for simple SAP. Stenting was performed in 43% (n=62) of successful SAP procedures. No death occurred in the perioperative period, while the 30-day mortality was 4.8% (7 of 145). The re-entry device (Outback) was used in 24 cases (16.5%). The technical success of the re-entry device was 79% (19 of 24), with a 90% success rate of stent placement at the site of re-entry. Complications occurred in 6.2% of all procedures (n=9) (three arterial perforations (2.1%), three distal embolisations (2.1%), two femoral artery pseudo-aneurysms (1.4%) and one arterio-venous fistula (0.7%)). Factors capable of independently affecting the patency were renal insufficiency (p=0.03), current smoking (p=0.01) and diabetes (p=0.04). The primary patency at 1 and 3 years was 70% and 34% and the secondary patency at 1 and 3 years was 77% and 43%, respectively. At the same time intervals, the limb-salvage rate was 88% and 49%.

CONCLUSIONS

SAP with the aid of a re-entry device for TASC C and D lesions of the SFA seems to be safe and clinically effective in patients suffering from CLI, according to the experience at our centre. Further follow-up and more data are necessary to confirm these findings.

Current literature for evidence-based infrainguinal endovascular treatment

With the proliferation of devices and techniques for lower extremity endovascular revascularization, treatment decisions become increasingly difficult as only limited experience with these new technologies is available for review. This monograph attempts to define the current state of the literature available to guide endovascular treatment of superficial artery disease, and to provide a baseline for future studies.