Atherectomy for infrainguinal peripheral artery disease

PERCUTANEOUS TRANSLUMINAL ROTARY ATHERECTOMY IN PATIENTS WITH ATHEROSCLEROTIC LESIONS OF BELOW THE KNEE ARTERIES

OBJECTIVE

The aim: To determine the effectiveness of the combination of the percutaneous transluminal rotational atherectomy (PTRA) techniques with plain old balloon angioplasty (POBA) and POBA monotherapy (POBA-mono) in endovascular treatment (ET) of patients with occlusive-stenotic lesions below the knee (BTK) arteries.

PATIENTS AND METHODS

Materials and methods: We studied two groups, the main included patients (n=9) aged who underwent PTRA and POBA of BTK arteries, and the comparative group (POBA-mono) of patients (n=24) who underwent POBA monotherapy of BTK arteries.

RESULTS

Results: Thrombosis of the reconstructed segments in the target arteries after 12 months was diagnosed in 95% of patients of the control and 1 - main groups (Ft, p=0.00001). Healing of trophic ulcers of the foot in the first month after ET was observed in 78% (n=7) of patients of the main group and in 13% (n=3) of the control group (χ2 (1, n=33) = 10.2961; p=0.0013), and after 3 months - in 100% (n=9) and 83% (n=20) of patients in the respective groups.

CONCLUSION

Conclusions: The combination of PTRA with POBA reduces the probability of repeated violations of the patency of the target artery. In addition, it increases the healing efficiency of trophic ulcers of the LE compared to POBA monotherapy.

Analytical Modeling of a New Compliant Microsystem for Atherectomy Operations

This work offers a new alternative tool for atherectomy operations, with the purpose of minimizing the risks for the patients and maximizing the number of clinical cases for which the system can be used, thanks to the possibility of scaling its size down to lumen reduced to a few tenths of mm. The development of this microsystem has presented a certain theoretical work during the kinematic synthesis and the design stages. In the first stage a new multi-loop mechanism with a Stephenson’s kinematic chain (KC) was found and then adopted as the so-called pseudo-rigid body mechanism (PRBM). Analytical modeling was necessary to verify the synthesis requirements. In the second stage, the joint replacement method was applied to the PRBM to obtain a corresponding and equivalent compliant mechanism with lumped compliance. The latter presents two loops and six elastic joints and so the evaluation of the microsystem mechanical advantage (MA) had to be calculated by taking into account the accumulation of elastic energy in the elastic joints. Hence, a new closed form expression of the microsystem MA was found with a method that presents some new aspects in the approach. The results obtained with Finite Element Analysis (FEA) were compared to those obtained with the analytical model. Finally, it is worth noting that a microsystem prototype can be fabricated by using MEMS Technology classical methods, while the microsystem packaging could be a further development for the present investigation.

Early outcomes of novel Temren atherectomy device combined with drug-coated balloon angioplasty for treatment of femoropopliteal lesions

OBJECTIVES

In this study, perioperative properties and early outcomes of patients who underwent combined Temren rotational atherectomy (RA) and drug-coated balloon (DCB) angioplasty treatment for complex femoropopliteal lesions in a single center were reported.

METHODS

Between June 2019 and February 2020, 40 patients who underwent combined Temren RA and DCB treatment due to critical lower limb ischemia or claudication-limiting daily living activities were retrospectively evaluated.

RESULTS

The mean age of patients was 73.2 ± 7.8 years and the majority of the patients were male (65%). Of the patients, 17 had critical limb ischemia and 23 had lifestyle-limiting claudication. Pathologies were total occlusion in 33 limbs and critical stenosis in seven limbs. Nine patients previously underwent endovascular intervention or surgery. The mean total occlusion length was 140.9 ± 100.9 (range, 20-360) mm in patients with chronic total occlusion. There was an additional iliac artery pathology in 5 and below the knee pathology in 8 patients. Rotational atherectomy was possible in all cases. Flow-limiting dissection was seen in six patients (15%). Provisional stent was performed to these patients. Following Temren RA, all patients underwent DCB. Adequate vascular lumen (less than 30% stenosis) was provided in all patients and the symptoms regressed. No distal embolization was encountered. Access site complications (17.5%) were small hematoma in four patients, ecchymosis in two patients, and pseudoaneurysm of the femoral artery in one patient. The mean follow-up was 13.55 ± 4.2 (range, 1-18) months. Re-occlusion was seen in three patients (7.5%) (n = 2 at 2 months and n = 1 at 4 months). Of these patients, two had required open revascularization via femoropopliteal bypass graft with common, superficial femoral, and popliteal artery endarterectomy and one had required femoro-posterior tibial artery bypass. Four minor toe amputations (10%) were performed to reach complete wound healing in the critical limb ischemia patients. A below-knee amputation was performed in a 94-year-old patient with long segment stenosis at the end of a 1-month follow-up period. There was no mortality after follow-ups. The Kaplan-Meier estimator estimated the rate of freedom from target lesion revascularization (TLR) which was 92.3%. The decrease in the Rutherford levels after the procedure was found to be statistically significant in 36 patients (p < 0.001). The increase in the ankle-brachial index after the procedure was found to be statistically significant in 36 patients (p < 0.001).

CONCLUSIONS

Combined use of Temren RA with adjunctive DCB is safe and effective method with high rates of primary patency and freedom from TLR and low rates of complication in the treatment of femoropopliteal lesions.

Atherectomy for peripheral arterial disease

BACKGROUND

Symptomatic peripheral arterial disease (PAD) has several treatment options, including angioplasty, stenting, exercise therapy, and bypass surgery. Atherectomy is an alternative procedure, in which atheroma is cut or ground away within the artery. This is the first update of a Cochrane Review published in 2014.

OBJECTIVES

To evaluate the effectiveness of atherectomy for peripheral arterial disease compared to other established treatments.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Allied and Complementary Medicine (AMED) databases, and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 12 August 2019.

SELECTION CRITERIA

We included all randomised controlled trials that compared atherectomy with other established treatments. All participants had symptomatic PAD with either claudication or critical limb ischaemia and evidence of lower limb arterial disease.

DATA COLLECTION AND ANALYSIS

Two review authors screened studies for inclusion, extracted data, assessed risk of bias and used GRADE criteria to assess the certainty of the evidence. We resolved any disagreements through discussion. Outcomes of interest were: primary patency (at six and 12 months), all-cause mortality, fatal and non-fatal cardiovascular events, initial technical failure rates, target vessel revascularisation rates (TVR; at six and 12 months); and complications.

MAIN RESULTS

We included seven studies, with a total of 527 participants and 581 treated lesions. We found two comparisons: atherectomy versus balloon angioplasty (BA) and atherectomy versus BA with primary stenting. No studies compared atherectomy with bypass surgery. Overall, the evidence from this review was of very low certainty, due to a high risk of bias, imprecision and inconsistency. Six studies (372 participants, 427 treated lesions) compared atherectomy versus BA. We found no clear difference between atherectomy and BA for the primary outcomes: six-month primary patency rates (risk ratio (RR) 1.06, 95% confidence interval (CI) 0.94 to 1.20; 3 studies, 186 participants; very low-certainty evidence); 12-month primary patency rates (RR 1.20, 95% CI 0.78 to 1.84; 2 studies, 149 participants; very low-certainty evidence) or mortality rates (RR 0.50, 95% CI 0.10 to 2.66, 3 studies, 210 participants, very low-certainty evidence). One study reported cardiac failure and acute coronary syndrome as causes of death at 24 months but it was unclear which arm the participants belonged to, and one study reported no cardiovascular events. There was no clear difference when examining: initial technical failure rates (RR 0.48, 95% CI 0.22 to 1.08; 6 studies, 425 treated vessels; very low-certainty evidence), six-month TVR (RR 0.51, 95% CI 0.06 to 4.42; 2 studies, 136 treated vessels; very low-certainty evidence) or 12-month TVR (RR 0.59, 95% CI 0.25 to 1.42; 3 studies, 176 treated vessels; very low-certainty evidence). All six studies reported complication rates (RR 0.69, 95% CI 0.28 to 1.68; 6 studies, 387 participants; very low-certainty evidence) and embolisation events (RR 2.51, 95% CI 0.64 to 9.80; 6 studies, 387 participants; very low-certainty evidence). Atherectomy may be less likely to cause dissection (RR 0.28, 95% CI 0.14 to 0.54; 4 studies, 290 participants; very low-certainty evidence) and may be associated with a reduction in bailout stenting (RR 0.26, 95% CI 0.09 to 0.74; 4 studies, 315 treated vessels; very low-certainty evidence). Four studies reported amputation rates, with only one amputation event recorded in a BA participant. We used subgroup analysis to compare the effect of plain balloons/stents and drug-eluting balloons/stents, but did not detect any differences between the subgroups. One study (155 participants, 155 treated lesions) compared atherectomy versus BA and primary stenting, so comparison was extremely limited and subject to imprecision. This study did not report primary patency. The study reported one death (RR 0.38, 95% CI 0.04 to 3.23; 155 participants; very low-certainty evidence) and three complication events (RR 7.04, 95% CI 0.80 to 62.23; 155 participants; very low-certainty evidence) in a very small data set, making conclusions unreliable. We found no clear difference between the treatment arms in cardiovascular events (RR 0.38, 95% CI 0.04 to 3.23; 155 participants; very low-certainty evidence). This study found no initial technical failure events, and TVR rates at six and 24 months showed little difference between treatment arms (RR 2.27, 95% CI 0.95 to 5.46; 155 participants; very low-certainty evidence and RR 2.05, 95% CI 0.96 to 4.37; 155 participants; very low-certainty evidence, respectively).

AUTHORS' CONCLUSIONS

This review update shows that the evidence is very uncertain about the effect of atherectomy on patency, mortality and cardiovascular event rates compared to plain balloon angioplasty, with or without stenting. We detected no clear differences in initial technical failure rates or TVR, but there may be reduced dissection and bailout stenting after atherectomy although this is uncertain. Included studies were small, heterogenous and at high risk of bias. Larger studies powered to detect clinically meaningful, patient-centred outcomes are required.

Successful Use of Adjunctive Orbital Atherectomy for Extensively Calcified Carotid Artery Lesions Using Flow Reversal Neuroprotection Technique

The use of transcarotid artery revascularization (TCAR) technique for carotid atherosclerotic disease has become increasingly popular as the endovascular alternative to traditional carotid endarterectomy. TCAR does offer a minimally invasive approach to carotid lesions, however, several technical and anatomic considerations, such as extensive calcification, limit its widespread applicability. Both orbital and rotational atherectomy are commonly used for extensively calcified lesions in the peripheral vasculature with satisfactory results for luminal gain. Herein, we describe the use of orbital atherectomy of a severely calcified ostial carotid lesion using reverse flow technique for neuroprotection during TCAR in a patient considered high risk for carotid endarterectomy.

When Are Endovascular and Open Bypass Treatments Preferred for Femoropopliteal Occlusive Disease?

Several meta-analyses and multicenter trials have shown that chronic limb ischemia did not occur for up to 5 years in 50%–70% of patients who underwent saphenous vein grafts, with limb salvage and perioperative mortality rates of >80% and 3%, respectively. However, open surgical bypass can have limitations, including postoperative morbidity/wound complications of 10%–20% and prolonged length of hospital stay and outpatient care. Several studies have analyzed clinical outcomes for patients with critical limb ischemia treated with endovascular therapies, but they have been mainly retrospective with significant heterogeneity or were single center. Only few randomized trials have compared surgical vs. endovascular therapy. These included the Bypass vs. Angioplasty in Severe Ischemia of the Leg (BASIL) trial, with no differences found in amputation-free or overall survival rates at 1 year; however, late outcomes favored the surgical group. The Bypass or Angioplasty in Severe Intermittent Claudication (BASIC) trial concluded that the 1-year patency rates were 82% and 43% for bypass and angioplasty, respectively. The BEST Endovascular vs. Best Surgical Therapy in Patients with Critical Limb Ischemia (BEST-CLI) trial is currently enrolling patients. This review analyzed studies comparing open vs. endovascular therapy in patients with femoropopliteal disease. (This is a review article based on the invited lecture of the 45th Annual Meeting of Japanese Society for Vascular Surgery.)

Safety and effectiveness of the Phoenix Atherectomy System in lower extremity arteries: Early and midterm outcomes from the prospective multicenter EASE study

Objectives

To evaluate the novel Phoenix Atherectomy System as percutaneous treatment of de novo and restenotic infrainguinal arterial lesions.

Methods

This prospective, multicenter, nonrandomized investigational device exemption trial was conducted across 16 US and German centers between August 2010 and April 2013. Intention-to-treat enrollment was 128 patients (mean age: 71.8 years, 59% male) with 149 lesions (mean length: 34 mm, mean diameter stenosis: 89.5%), and the primary analysis per-protocol population consisted of 105 patients with 123 lesions. The primary efficacy endpoint, technical success, was the achievement of acute debulking with a post-atherectomy residual diameter stenosis ≤50% (before adjunctive therapy). The primary safety endpoint was the major adverse event (MAE) rate through 30 days.

Results

For the primary analysis per-protocol population, the rate of lesion technical success was 95.1% (117/123), with the lower limit of the 95% CI 90.6%, meeting the prospectively established target performance goal of ≥86%. After post-atherectomy adjunctive therapy, residual stenosis was ≤30% for 99.2% (122/123) of lesions (mean final diameter stenosis 10.5%). Improvement of ≥1 Rutherford class occurred for 74.5% of patients through 30 days and for 80% through six months. MAEs were experienced by 5.7% (6/105) of patients through 30 days (with the upper limit of the 95% CI 11.0%, meeting the target performance goal of <20%), and 16.8% through six months. Six-month freedom from TLR and TVR was 88.0% and 86.1%, respectively.

Conclusions

Based on the high rate of technical success and the low rates of MAEs through six months, the Phoenix Atherectomy System is safe and effective for the debulking of lower-extremity arterial lesions.

ClinicalTrials.gov identifier NCT01541774

Successful Use of Orbital Atherectomy as an Adjunct in Treating Extensively Calcified Mesenteric Artery Lesions

BACKGROUND

To describe the use of orbital technique of atherectomy as an adjunct to successful angioplasty and stent placement of the superior mesenteric artery (SMA).

CASE REPORT

The technique is demonstrated in a 68-year-old man with critical SMA stenosis. The SMA was cannulated with 0.014-in wire, but the lesion was highly stenotic and densely calcified and prevented the passage of even the smallest 1.5-mm balloon. Orbital atherectomy was thus performed with a 1.25-mm CSI crown. Balloon angioplasty was then possible with a 4 mm × 2 cm balloon followed by placement of a 7 mm × 22 mm balloon-mounted stent.

CONCLUSIONS

The use of atherectomy as an adjunct to angioplasty and stenting in extensive, calcified SMA lesions supports the value of this technique to avoid a much larger and morbid open procedure.

Drug-coated balloon versus standard percutaneous transluminal angioplasty for the treatment of superficial femoral and popliteal peripheral artery disease: 12-month results from the IN.PACT SFA randomized trial

Supplemental Digital Content is available in the text.

Background—

Drug-coated balloons (DCBs) have shown promise in improving the outcomes for patients with peripheral artery disease. We compared a paclitaxel-coated balloon with percutaneous transluminal angioplasty (PTA) for the treatment of symptomatic superficial femoral and popliteal artery disease.

Methods and Results—

The IN.PACT SFA Trial is a prospective, multicenter, single-blinded, randomized trial in which 331 patients with intermittent claudication or ischemic rest pain attributable to superficial femoral and popliteal peripheral artery disease were randomly assigned in a 2:1 ratio to treatment with DCB or PTA. The primary efficacy end point was primary patency, defined as freedom from restenosis or clinically driven target lesion revascularization at 12 months. Baseline characteristics were similar between the 2 groups. Mean lesion length and the percentage of total occlusions for the DCB and PTA arms were 8.94±4.89 and 8.81±5.12 cm (P=0.82) and 25.8% and 19.5% (P=0.22), respectively. DCB resulted in higher primary patency versus PTA (82.2% versus 52.4%; P<0.001). The rate of clinically driven target lesion revascularization was 2.4% in the DCB arm in comparison with 20.6% in the PTA arm (P<0.001). There was a low rate of vessel thrombosis in both arms (1.4% after DCB and 3.7% after PTA [P=0.10]). There were no device- or procedure-related deaths and no major amputations.

Conclusions—

In this prospective, multicenter, randomized trial, DCB was superior to PTA and had a favorable safety profile for the treatment of patients with symptomatic femoropopliteal peripheral artery disease.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov. Unique Identifiers: NCT01175850 and NCT01566461.

The role of atherectomy in the treatment of lower extremity peripheral artery disease

Background

The incidence of lower extremity peripheral artery disease (LE-PAD) continues to increase and associated morbidity remains high. Despite the significant development of percutaneous revascularization strategies, over the past decade, LE-PAD still represents a unique challenge for interventional cardiologists and vascular surgeons.

Method

Typical features of atherosclerosis that affects peripheral vascular bed (diffuse nature, poor distal runoff, critical limb ischemia, chronic total occlusion) contribute to the disappointing results of traditional percutaneous transluminal angioplasty (PTA). New technologies have been developed in attempt to improve the safety and effectiveness of percutaneous revascularization. Among these, atherectomy, debulking and removing atherosclerotic plaque, offers the potential advantage of eliminating stretch on arterial walls and reducing rates of restenosis.

Conclusions

This review summarizes the features and the current applications of new debulking devices.

Mechanical recanalization of subacute vessel occlusion in peripheral arterial disease with a directional atherectomy catheter

PURPOSE

To retrospectively examine the technical feasibility and safety of directional atherectomy for treatment of subacute infrainguinal arterial vessel occlusions.

METHODS

Five patients (one woman, four men, age range 51-81 years) with peripheral arterial disease who experienced sudden worsening of their peripheral arterial disease-related symptoms during the last 2-6 weeks underwent digital subtraction angiography, which revealed vessel occlusion in native popliteal artery (n = 4) and in-stent occlusion of the superficial femoral artery (n = 1). Subsequently, all patients were treated by atherectomy with the SilverHawk (ev3 Endovascular, USA) device.

RESULTS

The mean diameter of treated vessels was 5.1 ± 1.0 mm. The length of the occlusion ranged 2-14 cm. The primary technical success rate was 100%. One patient experienced a reocclusion during hospitalization due to heparin-induced thrombocytopenia. There were no further periprocedural complications, in particular no peripheral embolizations, until hospital discharge or during the follow-up period of 1 year.

CONCLUSION

The recanalization of infrainguinal arterial vessel occlusions by atherectomy with the SilverHawk device is technically feasible and safe. In our limited retrospective study, it was associated with a high technical success rate and a low procedure-related complication rate.

Peripheral arterial disease: a literature review

INTRODUCTION

Peripheral arterial disease (PAD) is a common vascular condition that affects both quality of life and life expectancy with an increased risk of cardiovascular events.

SOURCES OF DATA

A literature search was carried out of Pub-Med, MEDLINE, the Cochrane Library and Google Scholar from the establishment of these databases up to February 2012. The search was performed by using the keywords 'peripheral arterial disease' and one of the following words: 'management', 'investigations', 'risk factors', 'epidemiology', 'revascularization', 'cryoplasty', 'atherectomy' and 'gene therapy'. Studies were limited to those published in English language.

AREAS OF AGREEMENT

Aggressive risk factors modification is needed to reduce cardiovascular-related mortality in PAD patients.

AREAS OF CONTROVERSY

Choice of endovascular or surgical intervention remains controversial in an ever-evolving field.

GROWING POINTS

There is a rapid expansion of endovascular technologies aiming to improve the effectiveness of this modality.

AREAS TIMELY FOR DEVELOPING RESEARCH

The advances in the fields of gene therapy and therapeutic angiogenesis mean these are potential future treatments. Tissue engineering is a developing area and aims to produce grafts with similar patency and infection profiles to those of autologous material. Further elucidation of the pathophysiology of atherosclerosis is required to provide new targets for pharmacotherapy.

Catheter-based therapy of common femoral artery atherosclerotic disease

The objective of this paper is to describe outcomes of endovascular therapy in patients with symptomatic common femoral artery (CFA) lesions. Symptomatic atherosclerotic disease of the common femoral artery is an uncommon clinical entity, and there is no consensus regarding the suitability of catheter-based therapy. We reviewed the records of 26 consecutive patients treated with catheter-based therapy for symptomatic CFA lesions between 1994 and 2009. Angiographic success and procedure success were obtained in all vessels and in all patients. At 1 year, 100% (16/16) of the claudication patients and 70% (7/10) of the critical limb ischemia (CLI) patients maintained clinical success. The ankle— brachial index (ABI) significantly improved from a baseline of 0.47 ± 0.18 to 0.77 ± 0.18 ( p < 0.001) after the procedure. At their most recent clinic visit (31 months ± 14 months), clinical success was maintained in 100% of the claudication patients and in 70% (7/10) of the CLI patients. During the follow-up period, femoral vascular access for an unrelated procedure was obtained through the CFA stent. In conclusion, patients with symptomatic CFA atherosclerotic disease obtained excellent clinical outcomes with angioplasty with stenting. We found that angioplasty with stenting of the CFA did not preclude future CFA vascular access. Our data suggest that catheter-based therapies should be considered as an option to open surgery in selected patients with symptomatic CFA disease.

Primary nitinol stenting for femoropopliteal disease

The 1- to 2-year primary patency rates associated with self-expanding nitinol stents for the treatment of symptomatic femoropopliteal disease are superior to those for percutaneous transluminal angioplasty (PTA) and the first-generation stainless steel balloon-expandable stents. The advantages of nitinol stents include improved radial strength and flexibility, the ability to recover from being crushed, reduced foreshortening, and (importantly) deployability without balloon dilation of the stent edge (which may decrease the incidence of the edge stenosis, or "candy-wrap" effect, often observed with balloon-expandable stents). The technical success rate associated with primary deployment of nitinol stents is very high, and acute to 6-month patency results are predictably excellent. Prior to the introduction of nitinol stents, the original guidelines (2000) of the multidisciplinary TransAtlantic Inter-Society Consensus (TASC I) recommended only an adjunctive role for femoropopliteal stents following suboptimal PTA. The abbreviated 2007 TASC II report essentially extended this recommendation to nitinol stents. Here, current trials of nitinol stenting in the femoropopliteal segment are discussed, with emphasis on the advantages of primary (and often direct) deployment in selected circumstances dependent on factors including lesion length, lesion location, indication for treatment (critical limb ischemia or claudication, in-stent restenosis, stent-graft restenosis), and the relative appropriateness of other modalities (e.g., covered stents). Technical considerations in primary nitinol stenting are briefly reviewed. Open questions regarding the factors involved in nitinol stent fracture and the possible association of fracture and restenosis are examined in the context of current clinical trials. A new generation of femoropopliteal nitinol stents combining superior durability and flexibility is expected soon. Development and implementation of uniform reporting and surveillance standards is important for optimizing current and future research.

Medical and endovascular management of critical limb ischemia

Critical limb ischemia (CLI) is the term used to designate the condition in which peripheral artery disease has resulted in resting leg or foot pain or in a breakdown of the skin of the leg or foot, causing ulcers or tissue loss. If not revascularized, CLI patients are at risk for limb loss and for potentially fatal complications from the progression of gangrene and the development of sepsis. The management of CLI requires a multidisciplinary team of experts in different areas of vascular disease, from atherosclerotic risk factor management to imaging, from intervention to wound care and physical therapy. In the past decade, the most significant change in the treatment of CLI has been the increasing tendency to shift from bypass surgery to less invasive endovascular procedures as first-choice revascularization techniques, with bypass surgery then reserved as backup if appropriate. The goals of intervention for CLI include the restoration of pulsatile, inline flow to the foot to assist wound healing, the relief of rest pain, the avoidance of major amputation, preservation of mobility, and improvement of patient function and quality of life. The evaluating physician should be fully aware of all revascularization options in order to select the most appropriate intervention or combination of interventions, while taking into consideration the goals of therapy, risk-benefit ratios, patient comorbidities, and life expectancy. We discuss the incidence, risk factors, and prognosis of CLI and the clinical presentation, diagnosis, available imaging modalities, and medical management (including pain and ulcer care, pharmaceutical options, and molecular therapies targeting angiogenesis). The endovascular approaches that we review include percutaneous transluminal angioplasty (with or without adjunctive stenting); subintimal angioplasty; primary femoropopliteal and infrapopliteal deployment of bare nitinol, covered, drug-eluting, or bioabsorbable stents; cryoplasty; excimer laser-assisted angioplasty; excisional atherectomy; and cutting balloon angioplasty.