|Year : 2020 | Volume
| Issue : 2 | Page : 33-39
Midterm outcome of directional atherectomy versus plain balloon angioplasty with adjunctive stenting for femoropopliteal artery lesions: A single-center experience
Yang Li1, Jianming Guo1, Yisha Tong2, Lianrui Guo1, Lixing Qi1, Zhu Tong1, Shijun Cui1, Shengjia Yang1, Yixia Qi1, Liang Meng1, Yongquan Gu1
1 Department of Vascular Surgery, Xuanwu Hospital and Institute of Vascular Surgery, Capital Medical University, Beijing, China
2 Department of Vascular Surgery, Austin Hospital, University of Melbourne, Melbourne, Australia
|Date of Submission||20-Feb-2020|
|Date of Decision||10-Mar-2020|
|Date of Acceptance||17-Mar-2020|
|Date of Web Publication||09-Jul-2020|
Dr. Yongquan Gu
Department of Vascular Surgery, Xuanwu Hospital and Institute of Vascular Surgery, Capital Medical University, Beijing
Source of Support: None, Conflict of Interest: None
OBJECTIVE: To examine the difference in safety and effectiveness of directional atherectomy (DA) and plain balloon angioplasty with adjunctive stenting (BA-STENT) in the treatment of de novo femoropopliteal artery occlusive lesions.
MATERIALS AND METHODS: This prospective, randomized trial of DA versus BA-STENT in femoropopliteal arteries was carried out in a single medical center. Demographic data, procedural characteristics, and follow-up information were recorded. The technical, procedural, and clinical outcomes were reported. The primary endpoint was the primary stenosis-free patency rate at 12 and 18 months after the intervention. The secondary endpoints included the rates of technical success, freedom from clinically driven target lesion revascularization (TLR), limb amputation, and all-cause mortality.
RESULTS: A total of 188 patients were included in this study. The DA group consisted of 89 (47.3%) patients, and the BA-STENT group consisted of 99 (52.7%) patients. There were 134 males and 54 females with an average age of 68 years, all of which had lesions of Rutherford Grade 2 and above. There was no statistically significant difference in age, gender, smoking, or comorbidities between two groups. The technical success rates were 98.9% in the DA group and 100% in the BA-STENT group (P = 0.47). There was no statistically significant difference in primary stenosis-free patency (90.0% vs. 90.6% at 6 months, 76.7% vs. 77.8% at 12 months, and 72.3% vs. 68.9% at 18 months after the intervention) or freedom from TLR (96.3% vs. 95.8% at 6 months, 88.3% vs. 91.6% at 12 months, and 86.1% vs. 85.4% at 18 months after the procedure) between the DA and the BA-STENT groups. There was no statistically significant difference in terms of distal embolization, thrombosis, and mortality between two groups. No patient underwent major amputation.
CONCLUSION: For the treatment of de novo Trans-Atlantic Inter-Society Consensus (TASC) II A-C femoropopliteal artery lesions, DA demonstrated comparable results with the plain balloon angioplasty with adjunctive stenting.
Keywords: Atherosclerosis, directional atherectomy, femoropopliteal artery, plain balloon angioplasty, stent implantation
|How to cite this article:|
Li Y, Guo J, Tong Y, Guo L, Qi L, Tong Z, Cui S, Yang S, Qi Y, Meng L, Gu Y. Midterm outcome of directional atherectomy versus plain balloon angioplasty with adjunctive stenting for femoropopliteal artery lesions: A single-center experience. Vasc Invest Ther 2020;3:33-9
|How to cite this URL:|
Li Y, Guo J, Tong Y, Guo L, Qi L, Tong Z, Cui S, Yang S, Qi Y, Meng L, Gu Y. Midterm outcome of directional atherectomy versus plain balloon angioplasty with adjunctive stenting for femoropopliteal artery lesions: A single-center experience. Vasc Invest Ther [serial online] 2020 [cited 2021 Jan 24];3:33-9. Available from: https://www.vitonline.org/text.asp?2020/3/2/33/289242
| Introduction|| |
With the improvement of living standards, the incidence of lower extremity arteriosclerosis occlusive disease has showed an obvious rising trend. The femoropopliteal artery is one of the common arteries affected by arteriosclerosis which can cause intermittent claudication, critical limb ischemia, and even amputation or death. The rate of amputation may exceed 70% at the end stage of the disease without medical intervention., Endovascular interventions such as balloon angioplasty and bare-metal stent (BMS) implantation have been widely used in vascular practice which has the advantages of fewer complications, less trauma, and rapid recovery compared with traditional surgery. In femoropopliteal lesions, the stress caused by knee joint movement on arteries may result in stent fracture, high rate of in-stent restenosis, and occlusion. It may also bring difficulties to subsequent treatment.
Since directional atherectomy (DA) system was approved for clinical application, it has been reported that DA has a good patency rate in the midterm.,, The “leave nothing behind” strategies may lead to better long-term patency rates, especially for patients who are not suitable for stent implantation, such as trans-knee joint lesions or severely calcified lesions. The purpose of this study was to compare the outcomes of DA and plain balloon angioplasty with adjunctive stenting (BA-STENT) for the treatment of de novo femoropopliteal artery disease.
| Materials and Methods|| |
A prospective, open-label, randomized trial of endovascular treatment of patients with symptomatic de novo femoropopliteal artery lesions was performed in the Department of Vascular Surgery, Xuanwu Hospital, Beijing, China, from August 2015 to September 2018. The trial was approved by the institutional ethics review committee and carried out following the Helsinki declaration. One hundred and eighty-eight patients were enrolled in the study and signed informed consent form. All patients had de novo femoropopliteal arteriosclerosis obliterans and suffered from lifestyle-limiting claudication or severe ischemic symptom (rest pain, ulceration, or gangrene). Patients were excluded from the study if they had one or more of the following conditions: (1) acute or subacute arterial thrombosis; (2) severely calcified lesions; (3) total occlusive lesions longer than 10 cm; (4) total occlusive lesions with high potential of subintimal wire recanalization; (5) with obstructed inflow or <1 runoff artery; (6) past history of lower extremity arterial bypass surgery or endovascular intervention; (7) severe liver insufficiency, or creatinine level > 2.5 mg/dL; (8) contraindications on antiplatelet or anticoagulation; (9) immunologic diseases or malignant diseases; (10) history of cerebrovascular diseases within 6 months or acute coronary syndrome; and (11) abnormal findings of platelets, protein C, protein S, or antithrombin III.
Intervention protocol and endovascular procedures
Preoperative duplex ultrasonography and computed tomography angiography (CTA) were performed in all patients to determine the severity and location of the arterial lesions. All patients received aspirin (100 mg/day) and clopidogrel (75 mg/day) at least 3 days before the intervention. Percutaneous puncture was performed with the Seldinger technique under local anesthesia. The contralateral femoral artery retrograde puncture or ipsilateral femoral artery antegrade puncture was used to establish the arterial access. A 0.035-inch guidewire and support catheter were advanced through the arterial lesion. Occlusive lesions were recanalized using different wires, catheters, and balloons; once the guidewire entered the true lumen distal to the lesion, the patients were assigned to DA or BA-STENT treatment by randomization.
In the DA group, after the guidewire entered the true lumen distal to the lesion, a Spider Filter might be placed in the popliteal artery for distal protection. The Silverhawk or Turbohawk DA system (Medtronic, USA) was used for DA. The use of embolic filter protection or the type of DA system was determined by the operator. If flow-limiting dissection or residual stenosis (>50%) was detected on angiogram, plain balloon dilation was performed (vessel: balloon = 1:1 in diameter) for the 60 s at low pressure. When the flow-limiting dissections or residual stenosis still existed, bailout stent was then inserted.
In the BA-STENT group, the stenosis was predilated by plain balloon angioplasty (the same diameter as the target vessel, 5 mm longer than the lesion segment, both proximally and distally) for at least 60 s. Nitinol BMS was then deployed, and the stent exceeded the vessel in diameter by 1 mm. The length of the stent was longer than the lesion by 5 mm, both proximally and distally.
After the procedure, two antiplatelet drugs (aspirin 100 mg/day and clopidogrel 75 mg/day) were taken orally for 3 months, and then oral aspirin 100 mg/day for life.
Patients were followed up at 30 days, and then at 3, 6, 12, and 18 months after endovascular interventions. Follow-up visits included assessment of clinical manifestations (claudication distance, relief of rest pain, ulcer healing), physical examination, Rutherford classification, ankle-brachial index (ABI), and vascular ultrasound examinations. When vascular ultrasound detected arterial restenosis (>50%), CTA or digital subtraction angiography was performed.
Endpoints and definitions
The primary endpoint of the trial was primary stenosis-free patency. Arterial stenosis or occlusion was determined by duplex ultrasound and CTA evaluations. Significant restenosis was defined by a >2.0 peak systolic velocity ratio calculated as the peak systolic flow velocity at the lesion divided by the peak systolic velocity 1 cm proximal to the lesion.
The secondary endpoints were technical success, freedom from clinically driven target lesion revascularization (TLR), limb amputation, and all-cause mortality. Technical success was defined as residual stenosis <30% and no flow-limiting dissection on final angiography.
Simple randomization was performed on a 1:1 basis. Enumeration data were presented as counts or proportions (%). Continuous data were presented as mean ± standard deviation. Difference between groups was analyzed using t-test or Chi-square test for enumeration data (or Fisher's exact test where the cell value was <5). The event occurrence time provided a two-sided P value with a significance level of 0.05 and a 95% confidence interval. Kaplan–Meier curves described the primary patency and freedom from TLR in the follow-up. Log-rank test was performed to compare differences between DA and BA-STENT groups. All the data were statistically analyzed with SPSS software (SPSS 20.0, Chicago, Illinois, USA).
| Results|| |
All 188 patients treated with DA or BA-STENT were followed up successfully and included in the analysis. Baseline clinical and demographic data were similar in the two groups [Table 1]. Among the 188 patients including 134 males (70.3%) and 54 females (29.7%) with an average age of 68 years, 89 were treated with DA and 99 with BA-STENT. Male patients accounted for 67.4% in the DA group and 74.7% in the BA-STENT group. Majority of these patients had histories of diabetes mellitus, hypertension, and smoking. Approximately 74.2% and 67.7% of patients suffered from ischemic claudication and 25.8% and 32.3% suffered from critical limb ischemia in the DA and BA-STENT groups, respectively. The preoperative baseline ABI was 0.57 ± 0.23 and 0.51 ± 0.25 in the DA and BA-STENT groups, respectively. The differences were not statistically significant.
There was no statistically significant difference in lengths, diameters or trigeminal-autonomic cephalalgias (TACS) II classification of the lesions, or number of runoff arteries between two groups [Table 2]. The locations of lesions were mainly in the proximal and middle superficial femoral artery (SFA) in both groups. Most of the lesions were classified as TASC II A/B, and only 6 (6.7%) and 7 (7.1%) were TASC II C lesions in DA and BA-STENT groups, respectively.
The technical success rates were 98.9% in the DA group and 100% in BA-STENT group (P > 0.05). Procedural characteristics are shown in [Table 3].
In the DA group, the Turbohawk atherectomy device was used in 21 patients, and the Silverhawk atherectomy device was applied in the remaining 68 patients. Fifteen (16.9%) patients received additional plain balloon dilatation due to residual stenosis. The use of embolic filter protection rate was 87.6% with a 67.4% of debris capturing rate. Embolic filter protection was not used in three patients and they suffered from the distal embolization.
In the BA-STENT group, four patients complicated with distal embolization during operation, and arterial flow was restored after catheter aspiration.
There were three patients in each group complicated with distal thrombosis. All of them were successfully treated with catheter-directed thrombolysis. One patient in each group suffered from a hematoma at the groin puncture site after the procedure. One patient in the DA group had upper gastrointestinal bleeding 1 day after the intervention and one patient in the BA-STENT group developed bloody stool 1 month after the procedure. One patient in the DA group experienced arterial perforation, which was successfully treated with the Viabahn covered stent placement. Six cases in the DA group developed dissection, four of which were flow-limiting and arterial flow was restored after stenting. Seventeen patients in the BA-STENT group developed dissections after balloon dilatation, and arterial flow was restored after stent implantation.
Results of follow-up
The mean follow-up was 14.5 ± 6.3 months in the DA group and 14.9 ± 6.8 months in the BA-STENT group. Primary stenosis-free patency rate and freedom from TLR rate are shown in [Table 4] and [Figure 1] and [Figure 2]. There was no statistically significant difference in the primary endpoint between the DA and BA-STENT groups. The primary stenosis-free patency rates in two groups were 90.0% versus 90.6%, 76.7% versus 77.8%, and 72.3% versus 68.9% at 6, 12, and 18 months after the intervention. The freedom from TLR rates in two groups were 96.3% versus 95.8%, 88.3% versus 91.6%, and 86.1% versus 85.4% at 6, 12, and 18 months after the procedure. During the follow-up, one patient in the DA group died from hypovolemic shock caused by gastrointestinal bleeding 2 months after the procedure. The mortality rate was 1.1%. No patient died in the BA-STENT group. No amputations were performed in either group. In clinical assessment, improvement of symptoms by 1 or 2 Rutherford Class was 91.0% versus 92.9% in DA and BA-STENT groups. The mean ABIs at 30 days after the intervention were 0.87 ± 0.20 and 0.91 ± 0.17 in DA and BA-STENT groups. Both were significantly improved compared with preoperative ABIs, P < 0.05.
|Figure 1: Two-year primary stenosis-free patency rate. Kaplan-Meier curves of patients assigned to DA (blue line) or BA-STENT (green line). DA: Directional atherectomy, BA-STENT: Plain balloon angioplasty with adjunctive stenting|
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|Figure 2: Two-year rate of freedom from target lesion revascularization. Kaplan-Meier curves of patients assigned to DA (blue line) or BA-STENT (green line). DA: Directional atherectomy, BA-STENT: Plain balloon angioplasty with adjunctive stenting|
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| Discussion|| |
The pathological basis of peripheral arterial disease is mainly the accumulation of macrophages, cholesterol, fatty acids, calcium, and fibrous connective tissue. This causes hyperplasia in the arteries, resulting in thickening of blood vessel walls and reduction of the lumen and may lead to insufficient tissue perfusion. Gradual development to complete occlusion increases the degree of distal ischemia. There are currently more than 200 million people affected by this disease worldwide, and its prevalence has increased by 28.7% and 13.1% in low- and middle-income countries over the past decade. Endovascular interventions such as balloon angioplasty and stent implantation use intraluminal forces to destroy and redistribute plaques along the arterial wall, but atherosclerotic plaques are not removed.
For harder, eccentric, severely calcified, atherosclerotic cases, balloon dilatation is less effective and vascular retraction is more common. A randomized controlled trial by Schillinger et al. confirmed that 1 year after BMS implantation, the primary patency of SFA lesions was 63%, which was significantly higher than that of 37% for plain balloon dilation, but it is still far from satisfactory. Although the BMS has a reasonable short-term patency rate in the treatment of femoropopliteal artery disease, stent fracture and in-stent restenosis bring difficulties to subsequent treatment.
DA can remove sclerotic plaques in the lumen and avoid problems associated with stent placement, such as stent fractures which is especially problematic in the treatment of lesions in the common femoral or popliteal artery., It can maximize the “volume reduction” of the diseased blood vessels, effectively avoiding the elastic contraction of the lumen, and then obtain a higher technical success rate and long-term patency rate.
Our study analyzed the effectiveness and safety of the two interventional techniques for treating femoropopliteal lesions. The technical success rates, primary stenosis-free patency rate, and the rates of freedom from TLR during the follow-up similar between the DA and BA-STENT group. No patient underwent major amputation in each group. Our results are compatible to other clinical studies of DA for femoropopliteal artery lesions. The TALON trial enrolled in 601 patients, 1258 lesions at 19 medical centers in the United States, of which approximately 50% were diabetic patients and 1/3 were critical lower extremity ischemia patients. The technical success rate was 97.6%, and the rate of freedom from TLR was 90% and 80% at 6 and 12 months, which was comparable to the plain balloon dilation combined stent implantation. Zeller et al. enrolled 84 patients with Rutherford Grades 2–5. The 100 lesions included 34% de novo lesions, 33% restenotic lesions, and 33% in-stent restenotic lesions. The technical success rate was 100%. Fifty-nine percent of patients received PTA, and 6% required bail-out stent placement. The primary patency rate of de novo lesions at 18 months was 73%, and the TLR rates of de novo lesions were 16% and 22% at 12 months and 18 months, respectively.
Theoretically, DA has little effect on the vascular wall compression, making the vascular formation more uniform, and reducing the plaque load in the lumen. Thereby, it can reduce the risk of artery wall retraction and dissection and prevent negative reconstruction and intimal hyperplasia. The DEFINITIVELE trial is the largest retrospective study to date, with 47 medical centers jointly analyzing 800 patients. The technical success rate was 89%. The need for combined plain balloon angioplasty accounted for 33%, and remedial stent placement accounted for 3%. The incidences of vascular complications, including distal embolism, dissection, and vascular rupture, were 3.8%, 2.3%, and 5.3%, respectively. Published studies suggested that DA can reduce the dissection rate, and the requirement for bailout stent implantation occurred in approximately 6% of patients.
The DA technique restores target vessel blood flow by directional plaque resection with less intima injury comparing with plain balloon dilation and therefore reduces vessel dissection and bailout stent implantation. In our study, the incidence of dissection in the DA group was 6.7%, which was significantly lower than 17.8% in the BA-STENT group. The bailout stent implantation rate was 4.5% in the DA group, which is similar to previously published data.
Shammas et al. reported 41 consecutive patients treated with SilverHawk atherectomy; the embolic filter protection was used in 56.1% of patients and distal embolization requiring treatment rate was 7.3%. In our study, chronic TASC-D occlusive lesions were not included. This may contribute to a lower incidence of distal embolization (3.4%). Distal embolization occurred in four patients in the BA-STENT group and three patients in the DA group who did not use embolic protection device. The embolic protection device was used in 87.6% of our patients. Of which, the debris capture rate was 67.4%. It is reported that the distal embolization rate of DA is 7%–9% with the protection of the embolic filter,,, and the debris capture rate is 20%–100%.,,, Distal embolism tends to occur in patients with severely calcified, complex, and occlusive lesions. Distal artery embolization is even more problematic for patients with single runoff artery. Our experience indicates application of the embolic protection device reduce distal artery embolization although it increases medical expenses.
| Conclusion|| |
For the treatment of de novo TASC II A-C femoropopliteal artery lesions, DA demonstrated comparable results with the BA-STENT, with a lower incidence of flow-limiting dissection. DA is an attractive treatment option which improves luminal diameter of target vessel without stent. This preserves future treatment options for patients with progressive, diffuse vascular disease. A multicenter randomized controlled study with a large sample size is needed to further clarify the advantages and disadvantages among different endovascular interventions.
Financial support and sponsorship
This work is supported by the National Key R and D Projects (2017YFC110410), Beijing Municipal Administration of Hospitals Climbing Talent Training Program (DFL20150801), Beijing Outstanding Talents Project (2016000020124G108), Beijing Healthcare System Specialist Training Program (2014-3-059) Beijing Municipal Administration of Hospitals Incubating Program (PX2018035), Beijing Municipal Administration of Hospitals Clinical Technology Innovation Project (XMLX201836), and Beijing Municipal Administration of Hospitals' Youth Program (QML20180804).
Conflicts of interest
There are no conflicts of interest.
| References|| |
Wolfe JH, Wyatt MG. Critical and subcritical ischaemia. Eur J Vasc Endovasc Surg 1997;13:578-82.
Fowkes FG, Rudan D, Rudan I, Aboyans V, Denenberg JO, McDermott MM, et al
. Comparison of global estimates of prevalence and risk factors for peripheral artery disease in 2000 and 2010: A systematic review and analysis. Lancet 2013;382:1329-40.
Krishnan P, Tarricone A, K-Raman P, Majeed F, Kapur V, Gujja K, et al
. Intravascular ultrasound guided directional atherectomy versus directional atherectomy guided by angiography for the treatment of femoropopliteal in-stent restenosis. Ther Adv Cardiovasc Dis 2018;12:17-22.
Stavroulakis K, Bisdas T, Torsello G, Argyriou A, Bollenberg L, Schwindt A. Optical coherence tomography guided directional atherectomy with antirestenotic therapy for femoropopliteal arterial disease. J Cardiovasc Surg (Torino) 2019;60:191-7.
Sauguet A, Philippart R, Honton B. Directional atherectomy with antirestenotic therapy for the treatment of no-stenting zones. J Cardiovasc Surg (Torino) 2019;60:198-204.
Stavroulakis K, Schwindt A, Torsello G, Stachmann A, Hericks C, Bosiers MJ, et al
. Directional atherectomy with antirestenotic therapy vs. drug-coated balloon angioplasty alone for isolated popliteal artery lesions. J Endovasc Ther 2017;24:181-8.
Katsanos K, Spiliopoulos S, Reppas L, Karnabatidis D. Debulking atherectomy in the peripheral arteries: Is there a role and what is the evidence? Cardiovasc Intervent Radiol 2017;40:964-77.
Lusis AJ. Atherosclerosis. Nature 2000;407:233-41.
Criqui MH, Aboyans V. Epidemiology of peripheral artery disease. Circ Res 2015;116:1509-26.
Katsanos K, Tepe G, Tsetis D, Fanelli F. Standards of practice for superficial femoral and popliteal artery angioplasty and stenting. Cardiovasc Intervent Radiol 2014;37:592-603.
Schillinger M, Sabeti S, Loewe C, Dick P, Amighi J, Mlekusch W, et al
. Balloon angioplasty versus implantation of nitinol stents in the superficial femoral artery. N
Engl J Med 2006;354:1879-88.
Shammas NW. An overview of optimal endovascular strategy in treating the femoropopliteal artery: Mechanical, biological, and procedural factors. Int J Angiol 2013;22:1-8.
Babaev A, Gokhale R, Zavlunova S, Attubato M. Treatment of angio-seal-related femoral artery occlusion using directional atherectomy-primary results and midterm follow-up. Vasc Endovascular Surg 2016;50:541-6.
Bracale UM, Vitale G, Bajardi G, Narese D, Dinoto E, Giribono AM, et al
. Use of the directional atherectomy for the treatment of femoro-popliteal lesions in patients with critical lower limb ischemia. Transl Med UniSa 2016;15:42-7.
Ramaiah V, Gammon R, Kiesz S, Cardenas J, Runyon JP, Fail P, et al
. Midterm outcomes from the TALON Registry: Treating peripherals with SilverHawk: Outcomes collection. J Endovasc Ther 2006;13:592-602.
Zeller T, Rastan A, Sixt S, Schwarzwälder U, Schwarz T, Frank U, et al
. Long-term results after directional atherectomy of femoro-popliteal lesions. J Am Coll Cardiol 2006;48:1573-8.
McKinsey JF, Zeller T, Rocha-Singh KJ, Jaff MR, Garcia LA; DEFINITIVE LE Investigators. Lower extremity revascularization using directional atherectomy: 12-month prospective results of the DEFINITIVE LE study. JACC Cardiovasc Interv 2014;7:923-33.
Vroegindeweij D, Tielbeek AV, Buth J, Schol FP, Hop WC, Landman GH. Directional atherectomy versus balloon angioplasty in segmental femoropopliteal artery disease: Two-year follow-up with color-flow duplex scanning. J Vasc Surg 1995;21:255-68.
Shammas NW, Shammas GA, Helou TJ, Voelliger CM, Mrad L, Jerin M. Safety and 1-year revascularization outcome of SilverHawk atherectomy in treating in-stent restenosis of femoropopliteal arteries: A retrospective review from a single center. Cardiovasc Revasc Med 2012;13:224-7.
Zeller T, Rastan A, Schwarzwälder U, Frank U, Bürgelin K, Amantea P, et al
. Midterm results after atherectomy-assisted angioplasty of below-knee arteries with use of the Silverhawk device. J Vasc Interv Radiol 2004;15:1391-7.
Kandzari DE, Kiesz RS, Allie D, Walker C, Fail P, Ramaiah VG, et al
. Procedural and clinical outcomes with catheter-based plaque excision in critical limb ischemia. J Endovasc Ther 2006;13:12-22.
Suri R, Wholey MH, Postoak D, Hagino RT, Toursarkissian B. Distal embolic protection during femoropopliteal atherectomy. Catheter Cardiovasc Interv 2006;67:417-22.
Spiliopoulos S, Theodosiadou V, Koukounas V, Katsanos K, Diamantopoulos A, Kitrou P, et al
. Distal macro- and microembolization during subintimal recanalization of femoropopliteal chronic total occlusions. J Endovasc Ther 2014;21:474-81.
Roberts D, Niazi K, Miller W, Krishnan P, Gammon R, Schreiber T, et al
. Effective endovascular treatment of calcified femoropopliteal disease with directional atherectomy and distal embolic protection: Final results of the DEFINITIVE Ca++
trial. Catheter Cardiovasc Interv 2014;84:236-44.
Mittleider D, Russell E. Peripheral Atherectomy: Applications and Techniques. Tech Vasc Interv Radiol 2016;19:123-35.
[Figure 1], [Figure 2]
[Table 1], [Table 2], [Table 3], [Table 4]