Treatment of femoropopliteal stenoses and occlusions with mechanical rotational catheters: comparison of results with the Rotarex and Pathway devices

AIM

For the treatment of chronic lesions, various ablative procedures have been developed with the aim of improving the outcome of percutaneous transluminal angioplasty (PTA)/stent and/or reducing the length and number of implanted stents by removing stenotic or occlusive material. The objective of this study was to compare two mechanical rotational catheters (Rotarex and Pathway) with regard to their safety and effectiveness in the treatment of stenoses and occlusions of the femoropopliteal arteries.

METHODS

A total of 156 patients with chronic stenoses or occlusions of the femoropopliteal vasculature were treated, 114 of them with the Rotarex catheter and 42 with the Pathway catheter. The pre-interventional Rutherford classification was on average 3.32 (2-5) in the Rotarex group and 2.93 (2-5) in the Pathway group. The mean lesion length was 13.9 cm (2-30 cm) and 5.1 cm (1-10 cm), respectively (P<0.05). The Ankle-Brachial Index (ABI) was determined pre- and postinterventionally and after 12 months. Colour-coded duplex ultrasound was additionally performed as a follow-up.

RESULTS

The technical success rate was 98.2 % in the Rotarex group and 97.6% in the Pathway group. In the Rotarex group, additional balloon dilatation was performed in 75 patients (65.8%) and stent implantation was necessary in 12 patients (10.5%). In the Pathway group, 27 patients (64.3%) underwent additional balloon dilatation and 5 (11.9%) stent implantation. Clinically, there was an increase in the ankle-brachial index from 0.59 to 0.84 ± 0.15 postinterventionally and 0.80 ± 0.16 12 months after Rotarex treatment, compared with an increase from 0.62 ± 0.14 to 0.84 ± 0.15 postinterventionally and 0.81 ± 0.12 12 months after Pathway treatment. In addition, there was a reduction in the Rutherford stage to 1.73 (1-3) and 1.43 (1-3), respectively. During the follow-up period, 21 (21.4%) restenoses occurred in the Rotarex group and 8 (19.0%) in the Pathway group. Peri-interventional complications included 7 dissections (4 after Rotarex, 3 after Pathway). Two distal embolisations were observed (both after Pathway). Throughout the entire duration of the study there were no amputations or fatalities.

CONCLUSION

The atherectomy of lesions of the femoropopliteal arteries using the Rotarex and Pathway systems is safe. The low stent rate peri-interventionally and the low restenosis rate after 12 months, with a significantly longer lesion length, indicate a better effectiveness of the Rotarex system as a whole.

Technological devices in peripheral percutaneous interventions

New innovations and novel approaches to peripheral arterial occlusive disease have brought enormous benefits to the vascular patient. Diseases that were once manageable only by surgical intervention are now easily and successfully treated by minimally invasive procedures. While the early days of percutaneous intervention were filled with inventions of new devices, today the focus centers on using modern technology and manufacturing to further improve upon these devices. Advances in guidewires and catheters have allowed us to visualize and treat lesions in nearly any vessel, and technology is guiding us towards specialized applications for specific lesions in specific vessels. However, one of the big hurdles remaining in treating arterial occlusive diseases is the rate of restenosis and the need for reinterventions. The location and architecture of these vessels make them uniquely difficult to treat, and call for new technology to address these challenges. Current developments of drug-eluting and bioabsorbable stents are at the forefront of new advancements specifically directed at improving current patency and restenosis rates; perhaps the next step in percutaneous intervention will rely on nanotechnology and the molecular surface engineering that may achieve a new era of devices that are able to target specific cell ligands or proteins to prevent the inflammatory and proliferative response from vessels. The present review will focus on the current literature regarding technological devices in peripheral percutaneous interventions and clinical applications. Future advancements in materials engineering and biotechnology will continue to improve the current standard of percutaneous intervention for peripheral arterial occlusive diseases.

Evolution of atherectomy devices

Percutaneous atherectomy provides an alternative approach to the endovascular treatment of peripheral atherosclerotic occlusive disease beyond angioplasty and stenting, and has the theoretical advantage of lesion debulking and minimizing barotrauma to the vessel wall. Atherectomy has evolved greatly during the last decade, with currently four FDA approved devices for the treatment of peripheral arterial disease. Several reports have focused on the initial technical success rates, and demonstrated the safety and short as well as mid-term efficacy of atherectomy devices. This article will review the evolution of current atherectomy devices and the associated literature.

Safety and efficacy of directional atherectomy for the treatment of in-stent restenosis of the femoropopliteal artery

AIM

The aim of this study was to evaluate safety and efficacy of directional atherectomy with the Silver HawkTM device as first line treatment for in-stent restenosis of the femoropopliteal artery.

METHODS

Over a period of 1.5 years in-stent restenosis of the femoropopliteal artery in 35 lesions (34 legs, 33 patients) was primarily treated with directional atherectomy. Primary endpoint was treatment success (<50% residual stenosis) and the absence of complications. Secondary endpoint was target lesion patency after 3, 6 and 12 month assessed by duplexsonography.

RESULTS

Mean patient age was 70 years (SD+/-10). 74 % were claudicants (Rutherford 2-3), 26% had CLI (Ruther-ford (4-5). 45% were diabetics, 82% had a history of arterial hypertension and nicotine abuse. Mean lesion length was 108 mm (SD+/-102 mm). Treatment success with atherectomy alone was achieved in 86% with additional PTA (43%) success increased to 97%. Adjunctive stent implantation was necessary in 11% of the cases. Post interventional ABI increased from 0.54 (+/-0.26) to 0.77 (+/-0.26). The rate of minor complication was 3% (1/34) and the rate of major complication was 18% (6/34), mainly due to distal embolization. Target lesion patency at 3 month was 86.2%, at 6 month 68% and at 12 month 25%.

CONCLUSIONS

Although atherectomy of in-stent restenosis as a first line treatment yields a high initial success rate with a low requirement for adjunctive PTA and stent implantation, long term patency rates are low. In our study the theoretical advantage of avoiding barotauma did not result in prevention of recurrent intimal hyperplasia.

[Clinical application of directional catheter-mediated atherectomy in patients with ischaemic-form diabetic foot syndrome]

The authors share their experience gained with the device designed for directional catheter-mediated atherectomy SilverHawk (eV3, U.S.A.) used as an alternative to the conventional procedure of balloon angioplasty and stenting in patients presenting with an ischaemic form of the diabetic foot syndrome. A conclusion was drawn on feasibility of directional catheter-mediated atherectomy in management of diabetic patients presenting with occlusive and stenotic lesions of lower-limb arteries.

Orbital atherectomy for infrapopliteal disease: device concept and outcome data for the OASIS trial

OBJECTIVE

The purpose of this study was to assess the safety and short-term efficacy of orbital atherectomy for chronic infrapopliteal arterial occlusive disease.

BACKGROUND

Infrapopliteal occlusive disease is a common cause of critical limb ischemia and claudication. There are no American College of Cardiology/American Heart Association guidelines for infrapopliteal revascularization for chronic limb ischemia.

METHODS

One hundred twenty four patients (201 stenoses) were enrolled in a prospective non-randomized multicenter registry of orbital atherectomy for severe infrapopliteal disease. Data were collected as part of an investigational device exemption from the Food and Drug Administration.

RESULTS

The primary safety endpoint of major adverse events (MAE) at 30-days (death, myocardial infarction, amputation, or repeat revascularization) was observed in four patients (3.2%). The primary efficacy endpoint (final diameter stenosis) was 17.8 +/- 13.5%. The secondary endpoints of procedural success (final diameter stenosis < or =30%) and 6 month MAE (death, amputation, or target vessel revascularization) were observed in 90.1 and 10.4% of patients, respectively. Stand-alone atherectomy was performed in 116 lesions (57.4%). At 6-months, no patients required surgical bypass or unplanned amputation, and improvement in Rutherford ordinal scale was observed in 78.2% of patients.

CONCLUSIONS

Orbital atherectomy is a unique approach to infrapopliteal disease, and provides predictable and safe lumen enlargement. Short-term data demonstrate substantial symptomatic improvement and infrequent need for further revascularization or amputation.

Analysis of particulate debris after superficial femoral artery atherectomy

PURPOSE

To evaluate the occurrence, size and composition of embolized debris captured during routine directional atherectomy using the SilverHawk device.

METHODS

15 consecutive eligible patients with a nonocclusive superficial femoral artery (SFA) were enrolled. Patients were included if they were > 18 years of age and had > or = 70% stenosis in the SFA. All lesions underwent plaque excision with the SilverHawk atherectomy device. A FilterWire EZ was used for distal protection and retrieval of embolized material. Specimens were collected separately from the filter basket and the SilverHawk atherectomy device's nosecone and were studied by a pathologist for number, size and composition.

RESULTS

Visible debris captured in the filter was found in the majority of patients 14/15 (93%). Clinically-significant debris was found in 7/15 (47%) patients. The proportion of captured debris ranged from 0.1-0.4 cm. Microscopy revealed that the shaved particles consisted predominantly of collagen, fibrin, lipid-laden macrophages, cholesterol and calcium. Analysis of the embolized material revealed a different composition, mostly consisting of collagen with fibrosis, cholesterol and macrophages.

CONCLUSION

In this single-center comparative study we have shown that during SilverHawk atherectomy of SFA lesions, distal embolization is universal. The debris captured in the filter is different in overall composition from the captured material in the nosecone of the SilverHawk device. Debris large enough to cause clinically-significant embolization, no-reflow and ischemia following SFA interventions occurred in nearly 50% of cases.

Popliteal artery pseudoaneurysm following FoxHollow atherectomy: a rare complication

Atherectomy using the FoxHollow device is an exciting treatment as an alternative to lower extremity arterial bypass for treatment of peripheral vascular disease in symptomatic patients with critical limb ischemia and disabling claudication. We present an interesting case of popliteal artery pseudoaneurysm following FoxHollow atherectomy, which is a rare complication. Mechanical factors have been implicated in causation of trauma to the vessel wall during atherectomy. Endovascular treatment of peripheral vascular disease has become increasingly common, thus it is important to know the rare complications associated with it. Pseudoaneurysm is one of the rare complications associated with the use of the FoxHollow atherectomy device.

Recent advances in atherectomy and devices for treatment of infra-inguinal arterial occlusive disease

The prevalence of peripheral arterial disease (PAD) continues to rise in an ever ageing society and consumes a significant part of health resources. Percutaneous revascularization has revolutionized the treatment of lower extremity peripheral vascular disease over the past 10 years. Additionally, novel devices have allowed improved endovascular treatment of femoropopliteal as well as infrapopliteal disease. Although percutaneous transluminal angioplasty (PTA) can be an effective modality for focal lesions in the iliac arteries, the results for complex infra-inguinal arterial disease have been disappointing. One class of new technology has concentrated on debulking the plaque, while others focus to improve safety (distal embolic protection devices) or are directed to specific clinical challenges such as chronic total occlusions. However, the lack of uniform performance criteria and reporting standards for these and other devices has resulted in heterogeneous study end points, making comparative efficacy difficult. Here we review the current data for atherectomy and atheroablative technologies as well as other adjunctive devices in the treatment of lower extremity peripheral arterial disease.

[Rotational ablation: back to the future]

In the late 1980s, many alternative methods to coronary angioplasty were sought, among which rotational ablation was one of the most popular. With the huge development of coronary stents, this technique, however, was progressively left aside. More recently, though, rotational ablation has reappeared as a unique technique for the most calcified lesions and is used in a small but not negligible percentage of patients with success rates over 95% in recent series.

Hybrid Revascularization Using Silverhawk Atherectomy and Infrapopliteal Bypass for Limb Salvage

Patients with limb-threatening ischemia and a paucity of ipsilateral greater saphenous vein for conduit represent a challenge for lower extremity revascularization. We present four patients with limited autogenous conduit who underwent hybrid revascularization using the Silverhawk atherectomy device and infrapopliteal artery bypass for limb-threatening ischemia. All patients experienced complete wound healing in early follow-up. Hybrid revascularization appears safe, produces excellent short-term outcomes, and may be appropriate for patients with limited autogenous vein who require lower extremity revascularization.

A novel approach using atherectomy for chronic total occlusion of the brachial artery: a case report

Chronic upper limb ischemia is uncommon, and is most often secondary to subclavian artery stenosis. Percutaneous intervention for subclavian stenosis usually includes balloon angioplasty and stent implantation. Brachial artery stenosis is even more scarce and accounts for approximately 12% of symptomatic upper extremity ischemia. Because it is rare, the optimal treatment strategy for brachial artery stenosis remains uncertain. We describe a case of chronic brachial artery ischemia due to atherosclerotic disease treated with the SilverHawk plaque excision system and review the available data regarding its use.

Treatment of severe infrapopliteal vascular disease using a novel atherectomy device: a case report

We report two first in man cases of percutaneous revascularization for severe intrapopliteal arterial disease using the novel PV atherectomy device.

Initial Experience with Directed Laser Atherectomy Using the Clirpath Photoablation Atherectomy System and Bias Sheath in Superficial Femoral Artery Lesions

PURPOSE

To report a safety and efficacy study of directed excimer laser atherectomy with the Bias Sheath guiding catheter to create larger lumens in the superficial femoral artery (SFA).

METHODS

Fourteen patients (9 men; mean age 66+/-9 years, range 46-76) with chronic lower limb ischemia (Rutherford class 2 to 5) referable to SFA stenoses were treated with the 8-F-compatible Bias Sheath and a 1.7- or 2.0-mm laser catheter. Eight (57%) lesions were de novo and 6 (43%) were in-stent restenoses (ISR). Mean diameter stenosis was 96%+/-8% (range 80%-100%; 10 total occlusions), and mean lesion length was 126+/-78 mm (range 30-290). The primary study endpoint was laser success, defined as <50% angiographic residual stenosis post-laser, without major perforations.

RESULTS

The primary endpoint was achieved in 8 (57%) lesions; all patients underwent additional balloon angioplasty, which achieved an angiographic residual stenosis <30% in all. Three lesions could not be completely traversed with the study device. Two dissections were detected after Bias Sheath application; 1 required stenting. There were 2 embolic events (specific to the antegrade device design); both were treated with aspiration therapy. Intravascular ultrasound (IVUS)-based minimal lumen diameters were 0.23+/-0.2 mm (range 0-1.0) at baseline and 3.2+/-0.8 mm after Bias Sheath application. Rutherford category improved at 1 month in 10 (71%) patients. One patient remained unchanged, another worsened (category 2 to 3), 1 died, and the fourth was not examined. The ankle-brachial index improved from 0.41+/-0.18 at baseline to 0.79+/-0.19 at discharge and to 0.80+/-0.19 at 1 month. Primary 1-month patency (<50% restenosis by duplex) was 85% (11/13 lesions).

CONCLUSION

SFA lesions, including ISR, can be treated in the majority of cases with directed laser atherectomy, significantly reducing plaque burden as measured by IVUS. Embolization was attributed to device-specific features of the prototype antegrade sheath design, which was discontinued. Larger studies are mandatory to document the long-term technical and clinical impact of this new device.

Percutaneous Rotational and Aspiration Atherectomy in Infrainguinal Peripheral Arterial Occlusive Disease: A Multicenter Pilot Study

PURPOSE

To report a safety and efficacy study of the first rotational aspiration atherectomy system (Pathway PV) for the treatment of arterial lesions below the femoral bifurcation.

METHODS

From December 2005 to February 2006, 15 patients (9 men; mean age 71+/-9 years) with Rutherford stage 2 to 5 lower limb ischemia were enrolled at 3 study sites. Target lesions were in the superficial femoral (n = 7, 47%), popliteal (n = 7, 47%), and posterior tibial (n = 1, 6%) arteries. Mean diameter stenosis was 97%+/-10%; mean lesion length was 61+/-62 mm (range 5-250). The primary study endpoint was the 30-day serious adverse event (SAE) rate.

RESULTS

Interventional success (residual stenosis <30%) was achieved in all lesions (100%). Stand alone atherectomy was performed in 6 (40%) patients, adjunctive balloon angioplasty in 7 (47%), and stenting/endografting in 2 (13%). The SAE rate at 30 days was 20% (3/15), including 1 perforation due to an unrecognized displacement of the guidewire (sealed with an endograft), 1 false aneurysm at the puncture site (successful duplex-guided compression therapy), and 1 dissection in conjunction with a distal embolism (stent implantation and aspiration thrombectomy). Primary patency rates measured by duplex ultrasound at 1 and 6 months were 100% and 73%, respectively; the TLR rate was 0% after 6 months. The ankle-brachial index increased significantly from 0.54+/-0.3 at baseline to 0.89+/-0.16, 0.88+/-0.19, and 0.81+/-0.20 (p<0.05) at discharge, 1 month, and 6 months, respectively. Mean Rutherford categories were 2.92+/-1.19 (range 1-5), 0.64+/-1.12 (range 0-1), and 0.83+/-1.33 (range 0-3) at the same time points (p<0.05).

CONCLUSION

The application of this new atherectomy device was feasible in all cases. The serious adverse event rate was moderate; however, all events were solved during the index procedure. The 0% 6-month TLR rate is promising.

Recanalization of infrainguinal vessels: silverhawk, laser, and the remote superficial femoral artery endarterectomy

There are multiple endovascular options to achieve percutaneous revascularization of chronic superficial femoral artery (SFA) stenoses and occlusions. Most rely on forceful displacement of plaque via balloon angioplasty, either as a stand-alone therapy or supplemented by cold thermal injury (cryoplasty), microtome assistance (cutting balloon angioplasty), nitinol stent deployment, or expanded polytetrafluoroethylene-lined nitinol stent deployment. Excellent technical success rates are routinely described in the literature. The essential problem associated with these techniques is the predictable compromise of the initial result by neointimal hyperplasia leading to poor long-term results. An alternative to forceful displacement techniques is use of directional atherectomy or excimer laser to debulk the atheromatous lesion, with the addition of low-pressure angioplasty or stent deployment as needed. Currently, directional atherectomy is performed using the Silverhawk Plaque Excision System (FoxHollow, Redwood City, CA), while laser atherectomy is frequently performed with the CLIRpath Excimer Laser (Spectranetics Corp., Colorado Springs, CO). While both techniques can be utilized for de novo atherosclerotic lesions, even eccentric lesions or ostial lesions, proponents of these devices have also shown good short-term results in the treatment of restenoses. Remote SFA endarterectomy with the Aspire stent (Vascular Architects, San Jose, CA) is a hybrid surgical and endovascular technique that is useful for debulking plaque from the SFA with adjunctive stenting of the distal SFA. We present a review of various alternative techniques to forceful balloon dilation used in the recanalization of the SFA with potential pitfalls and complications, along with a review of literature associated with each of these techniques.

Mechanism of Luminal Gain with Plaque Excision in Atherosclerotic Coronary and Peripheral Arteries: Assessment by Histology and Intravascular Ultrasound

OBJECTIVES

Using intravascular ultrasound (IVUS) and histology, the purpose of this study was to evaluate the occurrence of arterial wall overstretch and Dotter effect following revascularization with a plaque excision (PE) catheter compared with balloon angioplasty.

BACKGROUND

Previous studies have demonstrated the safety and feasibility of plaque excision for the treatment of de novo coronary and peripheral atherosclerotic disease. However, whether mechanical vessel dilatation related to catheter insertion contributes to gains in the final luminal diameter is uncertain.

METHODS

Treatment with PE was assessed in both a porcine model (6 lesions treated with balloon angioplasty or PE) using histology and in humans with IVUS. In the latter part of the study, IVUS study was performed before and immediately following PE in 21 patients with either coronary artery disease (N = 13) or femoral artery disease (N = 8). Ultrasound measures in the femoral artery group were then compared with a control group of atherosclerotic lesions treated with conventional angioplasty that was matched according to lesion location and vessel diameter.

RESULTS

Among individuals with coronary and peripheral arterial lesions treated with PE, the relative increases in luminal area secondary to reductions in plaque volume were 89% and 83%, respectively, with minimal increase in vessel diameter. In contrast, balloon angioplasty was associated with significantly greater vessel expansion and less plaque volume reduction. Vessel dissection also tended to occur less frequently and to a lesser extent with PE.

CONCLUSIONS

Improvement in luminal dimensions using PE is principally due to a reduction in plaque volume rather than mechanical vessel expansion. The potential to increase luminal area while minimizing arterial dissection and barotrauma merits further clinical study with this method of revascularization.

[Treatment for coronary artery calcification]

Coronary calcification frequently coexists with coronary atherosclerosis. Diagnosis methods are traditional coronary angiography, intravascular ultrasound, electron beam CT and muti-slice CT. Treatment for patients with calcified coronary arteries is troublesome. Rotablator or laser atherectomy are candidates for the treatment in coronary intervention. In bypass surgery, calcified area should be avoided for anastomosis. Treatment for coronary calcification itself is not standardized at present.

Ostial RCA intervention: guiding catheter challenges and use of a buddy wire to perform focused-force angioplasty on a severely calcific ostial right coronary lesion

Ostial coronary disease presents a challenge from multiple perspectives with regard to percutaneous intervention. We present a novel case of a technically challenging ostial right coronary artery calcified lesion with a bar of calcium at the aorto-ostial junction which prevented intubation with multiple guiding catheters. We describe the use of a buddy wire as a technique for focused-force angioplasty with slow incremental balloon inflation of increasing diameter for plaque modification prior to stenting in a situation where rotational atherectomy and cutting balloon angioplasty were not an option.

Plaque Excision in the Treatment of Peripheral Arterial Disease

The goals of any percutaneous intervention in the lower extremity are to provide initial technical success and restore durable arterial patency. The first goal can be achieved through a multitude of endovascular techniques, whereas achieving the latter has remained elusive. The large number of choices in treatment options for percutaneous lower-extremity revascularization speak to the fact that no single tool or technique has been proven to be superior. The SilverHawk plaque excision system is designed to debulk stenotic or occlusive arterial lesions. Like many endovascular technologies, reports have focused on rates of initial technical success and short-term outcomes, but long-term results remain unknown. This report reviews selected published or presented results of plaque excision, touches on areas of concern or controversy regarding both the device and some of its proponents, and suggests clinical or anatomic settings in which plaque excision appears most effective. The ultimate utility of this technology will depend on confirmation of its acute and long-term outcomes through unbiased, well-designed clinical trials.