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Safety and One-Year revascularization outcome of excimer laser ablation therapy in treating in-stent restenosis of femoropopliteal arteries: A retrospective review from a single center
Cardiovascular Revascularization Medicine 13 (2012) 341–344
Contents lists available at SciVerse ScienceDirect
Cardiovascular Revascularization Medicine
Review
Safety and One-Year revascularization outcome of excimer laser ablation therapy in treating in-stent restenosis of femoropopliteal arteries: A retrospective review from a single center☆ Nicolas W. Shammas ⁎, Gail A. Shammas, Alexander Hafez, Ryan Kelly, Emily Reynolds, Andrew N. Shammas Midwest Cardiovascular Research Foundation, Davenport, IA, USA
a r t i c l e
i n f o
Article history: Received 15 July 2012 Received in revised form 30 August 2012 Accepted 31 August 2012 Keywords: Atherectomy In-stent restenosis femoropopliteal segment Excimer Laser long term outcome
a b s t r a c t Background: Treatment of in-stent restenosis of the femoropopliteal (FP) arteries is challenging with a high rate of restenosis. Excimer laser atherectomy (ELA) has a theoretical advantage of ablating restenotic tissue and reducing or delaying the need for repeat revascularization. We present a retrospective analysis from our center on the outcomes of ELA in the treatment of in-stent restenosis of the FP arteries. Methods: Demographic, clinical, angiographic and procedural data were collected on all patients that underwent ELA for in-stent restenosis from February 2005 to April 2010 at a single medical center. Major adverse events and one-year target lesion revascularization (TLR) and target vessel revascularization (TVR) were obtained by reviewing of medical records. Descriptive analysis was performed on all variables. Kaplan– Meier survival curves for TLR were plotted. Results: 40 consecutive patients (mean age 67.7±9.0 years, 57.5% males) were included and followed for 1 year. Adjunctive balloon angioplasty was performed in 100% at a mean pressure of 12.4±2.9 atm. Acute procedural success (b30% angiographic residual narrowing) occurred in 92.5% of patients. Embolic filter protection (EFP) was used in 57.5% of patients. Bailout stenting was 50.0%. Macrodebris was noted in 65.2% of filters. The following adverse events were reported: distal embolization (DE) requiring treatment 2.5% (1 patient with no EFP); planned minor amputation 2.6%, planned major amputation 2.6%, total death 7.7% (all cardiac related). One perforation occurred treated successfully with stenting and balloon inflation. At one year, TLR and TVR occurred in 48.7% and 48.7% respectively. Conclusion: ELA has an overall favorable acute result in treating in-stent restenosis of the FP arteries. At one year TLR and TVR remain clinically significant. DE also occurs significantly with ELA and is effectively prevented with EFP. © 2012 Elsevier Inc. All rights reserved.
1. Introduction Several studies have shown that stenting of the femoropopliteal artery (FP) leads to higher long term patency and less target lesion revascularization (TLR) [1–4]. Stenting however, has several disadvantages including a continued high rate of restenosis and stent fractures [5,6]. Treatment of these in-stent restenotic (ISR) lesions has a high procedural success rate but distal embolization (DE), the need for additional stenting and recurrent restenosis remain prevalent [7– 10]. Several methods have been proposed to treat in-stent FP lesions including plain old balloon angioplasty (POBA) [10], PolarCath ☆ Conflict of Interest: This study is supported by the Nicolas and Gail Research Fund at the Midwest Cardiovascular Research Foundation. No commercial support was provided for this project. Dr NW Shammas does not have any equity or financial interest in any medical device or drug listed in this manuscript. Full COI at www. mcrfmd.com. ⁎ Corresponding author. Cardiovascular Medicine, PC, 1236 E Rusholme, Suite 300, Davenport, IA 52722. Tel.: +1 563 320 0263. E-mail address: [email protected] (N.W. Shammas). 1553-8389/$ – see front matter © 2012 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.carrev.2012.08.012
(Boston Scientific, Natick, Mass) cryoplasty [11], cutting balloons [10], drug-eluting self-expanding stents (Zilver X) (Cook Medical, Bloomington, IN, USA) [12], atherectomy with (Rotarex S) (Staub Medical AG, Wangs, Switzerland) [13,14] or without (SilverHawk) (Covidien, Mansfield, MA) [7–9,15,16] embolectomy, and laser ablation (Excimer laser) (Spectranetics, Colorado Springs, Co, USA) [17] with adjunctive covered stents (Viabahn) (W.L. Gore and Associates, Newark, DE) [18]. Debulking of in-stent restenotic FP lesions have been attempted to reduce restenotic tissue burden and theoretically delay or reduce the rate of repeat revascularization. The off label use of SilverHawk atherectomy (Covidien, Mansfield, MA) in these lesions has been shown to have high procedural success but skills and techniques of the operator are important to avoid complications [7–9]. To our knowledge there are no published randomized data to date on angioplasty versus stenting or debulking (with the SilverHawk or the Excimer laser) of in-stent restenotic FP lesions. Coronary studies have shown that laser effectively ablates restenotic tissue and thrombus, commonly found in occlusive in-stent
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Table 1 Demographics and clinical characteristics. n
mean±SD
Age Body Mass Index Baseline ABI of treated Leg at rest Baseline ABI of treated leg with exercise
40 39 35 25
67.7±9.0 28.9±5.6 0.63±0.2 0.38±0.2
Gender-male Prior percutaneous coronary intervention Prior coronary bypass surgery Previous myocardial infarction Family History Premature CAD Renal Failure (CreatinineN2.0) Chronic obstructive lung disease Hypertension Cerebrovascular disease Hyperlipidemia history of smoking Diabetes Mellitus Onset of symptoms-Subacute Onset of symptoms-chronic Claudicants (Rutherford Becker 1–3) Limb ischemia (Rutherford Becker 4–5)
23/40 22/40 9/40 7/40 14/40 2/40 1/40 34/40 9/40 32/40 33/40 19/40 22/40 16/40 28/38 10/38
Percentage 57.5 55.0 22.5 17.5 35.0 5.0 2.5 85.0 22.5 80.0 82.5 47.5 55.0 40.0 73.7 26.3
ABI=ankle brachial index.
restenosis of FP lesions [19–24]. Excimer laser also suppresses platelet aggregation and therefore potentially reduces the chance of platelet mediated thrombotic reocclusion [25]. Although acute results appear to be satisfactory in ablating restenotic tissue, the long term outcome has been variable and may be related to the extent of tissue debulking [26]. In this study, we evaluate the acute procedural and long term outcome of ISR FP lesions treated with the excimer laser. Secondary endpoints included the safety of the laser within stented segments, bail-out stenting and distal embolization. 2. Methods 457 patients with FP disease were treated by 2 operators at our medical center from February 2005 to April 2010. Patients were included if their index lesions were restenotic, in-stent and were only in the FP arteries. Patients were excluded if they had de novo lesions or non FP segments treated during the index procedure or if they were treated with a non excimer laser atherectomy device. There were no prespecified guidelines to the choice of the device which was based on operator's judgment. Demographics, clinical, procedural and angiographic variables were retrospectively reviewed from a prospective peripheral vascular database developed at our institution. One-year follow up was achieved on all patients by reviewing medical records by a dedicated research coordinator. The study was approved by the Institutional Review Board (IRB). In-hospital and 1-year major adverse events including amputation (major and minor, planned and unplanned), death, vessel perforation, distal embolization (as captured by an embolic filter or distally embolized and requiring further treatment with pharmacologic or mechanical means), major bleeding, myocardial infarction, stroke, access complications, acute renal failure, and acute or subacute vessel closure. Major bleeding was defined as a drop ofN3 gm/dl Hb with a clear source of bleed, retroperitoneal bleed, or intracranial bleed. Acute renal failure was defined as an increase in creatinine within 48–72 h of the procedure byN0.5 mg per dl. The Trans-Atlantic Inter-Society Consensus (TASC I) [27] was used to classify lesion complexity. The primary effectiveness endpoint was acute procedural success defined as obtaining angiographically less than 30% residual narrowing respectively with no serious adverse events at the end of the procedure [7]. Secondary endpoints included acute device success
defined as a residual narrowing ofb50% by the ELA device alone and before adjunctive treatment, DE, clinically driven TLR and TVR at one year based on symptom recurrence, ankle brachial indices (ABI) and Rutherford–Becker class at one month, 6 months and one year in TLRfree patients, death, and amputation. Patients were followed up at approximately 1 month, 6 month and one year intervals in the office. Follow-up ABI testing was not part of a mandatory protocol but was generally done on the majority of patients. Descriptive analysis was done on all variables. Continuous variables were presented as mean±SD and dichotomous variables as percentages. Kaplan–Meier survival curve for TLR was plotted. 3. Results Of 457 FP treated patients, 123 were treated with excimer laser. 83 patients did not meet the inclusion criteria (de novo lesions=67; devices used other than balloon or stent post laser =7; use of balloon or an atherectomy/embolectomy device before laser=2; non-index procedure in patients treated with 2 separate procedures with the laser in the same FP segment =7). 40 patients met the inclusion criteria and formed the cohort of this study. Demographic and clinical variables are presented in Table 1. Patients had multiple comorbidities with a high frequency of hypertension (85.0%), hyperlipidemia (80.0%), smoking history (82.5%) and diabetes (47.5%). The majority of the patients were claudicants (73.7%) and with subacute (b 1 month, N 24 h) (55%) or
Table 2 Angiographic and procedural characteristics.
Number of runoff vessels of treated leg Prestenosis severity (%) Poststenosis severity (%) Lesion length (mm) Lesion diameter (mm) Balloon pressure (mmHg) Laser parameters Fluency (mJ/mm2) Repetitions (Hz) Total Pulses Total laser time (s) Laser catheter size (mm)
n
mean±SD
40 40 40 35 40 39
1.7±1.0 93.9±8.9 14.0±13.0 210.4±104.0 5.6±0.7 12.4±2.9
21 27 24 24 38
56.2±13.6 60.0±20.6 11476±9063 188.6±138.6 2.2±0.3
39/40 40/40 20/40
97.5 100.0 50.0
15/20 2/20 2/10 1/20 13/25 37/40 0/40
75.0 10.0 10.0 5.0 52.0 92.5 0
5/40 16/40 19/40
12.5 40 47.5
30/35 5/35 23/40
85.7 14.3 57.5
6/23 2/23 15/23 1/40
26.1 8.7 65.2 2.5
Percentage Intraprocedural anticoagulant-bivalirudin Adjunctive Balloon use Bailout Stent Reason for Bailout stent N 30% residual N 30% residual and type C or higher dissection Investigator discretion Perforation Device success (b50% residual with laser alone) Procedural success (b30% residual at end of treatment) In-hospital major adverse events TASC type FP-B FP-C FP-D Laser type Elite Booster or tandem Embolic filter use Debris None Microembolization Macroembolization Distal Embolization requiring treatmenta TASC=Trans-Atlantic Inter-Society Consensus. FP=femoropopliteal. a No filter used.
N.W. Shammas et al. / Cardiovascular Revascularization Medicine 13 (2012) 341–344
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Table 3 Ankle–Brachial Index and Rutherford Becker class in patients free of target lesion or vessel revascularization at 1 year.
ABI ABI ABI ABI
(baseline) (30 days) (6 months) (1 year)
Median Median Median Median
Rutherford Rutherford Rutherford Rutherford
Becker Becker Becker Becker
(baseline) (30 days) (6 months) (1 year)
n
Mean±SD
17 12 10 8
0.6±0.2 1.0±0.1* 0.9±0.1^ 0.9±0.2#
n
Median
21 22 18 16
3.0 1.0** 0.0^^ 0.5##
Compared to ABI baseline: *p=0.000, ^p=0.003, #p=0.017. Compared to Rutherford Becker baseline: **p=0.002, ^^p=0.000, ##p=0.0002.
chronic symptoms (N 1 month) (40.0%). Angiographic and procedural variables are presented in Table 2. The mean lesion length was 210.4 ± 104.0 mm and 47.5% of lesions were TASC D. Procedural and device successes were achieved in 92.5% and 52.0% of patients respectively. Bail out stenting was performed in 50% of patients. Macroembolization occurred in 65.2% of filters. One patient with DE required additional treatment successfully. Among patients who did not have TLR there was continued stable improvement in ABI and Rutherford Becker class up to one year (Table 3). At one year there were more patients in Rutherford class 0 and 1 than baseline (Fig. 1). Also, compared to baseline, ABI at one month also significantly improved to 1.0±0.1 (p=0.000) and remained stable at one year (0.9±0.2). There were 3 deaths, all cardiac, and 2 unplanned amputations (1 minor and 1 major). TVR and TLR (Fig. 2) were 48.7% and 48.7% respectively (Table 4). There was no major bleeding or acute renal failure. One-year follow up was achieved on 39/40 (97.5%) patients.
4. Discussion In-stent restenosis is a prevalent problem in the FP segment occurring in 19% to 37% of treated lesions at 1 year [1,2,28,29] and up to 49% at 2 years [3]. Predictors of in-stent restenosis in the first year post treatment include female gender, diabetes mellitus, critical limb ischemia, stent fracture and Trans-Atlantic Inter-Society Consensus II C/D lesions [30]. Also lesion length correlates with increased restenosis in treating FP segments [29,31]. Revascularization of FP ISR lesions with stable long term results remains a challenge to the endovascular specialist. Freedom from TLR remains low with POBA (64%) at 6 months even in relatively short ISR lesions [10]. In the COBRA trial [11], binary restenosis with POBA remains high at one year at 55.8% in all lesions and 70% in patients with total occlusions. This is consistent with reported primary patency with POBA of 69% in in-stent stenotic lesions and 23% in in-stent total occlusions [32]. Several methods have been attempted to treat FP ISR with variable success including cutting balloon [10], cryoplasty [11], Zilver PTX self-
Fig. 1. Rutherford Becker class in patients with no target lesion revascularization at baseline, 1 month, 6 months and 1 year after excimer laser treatment.
expanding drug eluting nitinol stent [12], Rotarex S atherectomy [13,14], SilverHawk atherectomy [7–9,15,16] and laser ablation (Excimer laser) with adjunctive covered stents (Viabahn) [18]. There are no published randomized data to evaluate the role of ELA in the treatment of FP ISR lesions. Laird et al. [18] recently reported the results of the SALVAGE trial with the use of the excimer laser and the Viabahn (W.L. Gore and Associates, Newark, DE) covered stent in treating FP ISR. The primary patency at 12 months was measured by duplex ultrasonography. Twenty-seven patients were enrolled. The mean lesion length was 200.7 mm and the majority of lesions were TASC C/D. Procedural success was achieved in 100% of cases. Primary patency and TLR at 12 months were 48% and 17.4% respectively. This prospective single arm registry does not distinguish, however, between the relative effectiveness of the laser versus the Viabahn endograft stent in reducing restenosis in FP ISR lesions. In our study, ELA with or without adjunctive balloon angioplasty or stenting had a TLR of 48.7%. This rate remains significantly high, presumably related to the high prevalence of diabetes, TASC D and very long lesions; all are associated with restenosis in the FP segment [29–31]. The 6-month interim results from the PATENT (PhotoAblation Using the Turbo-Booster and Excimer Laser for In-Stent Restenosis Treatment) study were recently presented [17]. PATENT is a prospective registry evaluating laser atherectomy for treating FP ISR. Data on 78 patients were presented. Mean lesion length was 125 mm and 37% were total occlusions. 50% of these patients were diabetic. At 6 months, TLR rate was 24%. Our registry included significantly longer lesions (200.7 mm vs. 125 mm) and more total occlusions than
Table 4 Long term outcomes of Excimer laser atherectomy. Time to Target lesion revascularization (days)
Target vessel revascularization (%) Target lesion revascularization (%) Planned major amputation (%) Planned minor amputation (%) Death (%)⁎ ⁎ All deaths were cardiac related.
167.0±83.3 n
percentage
19/39 19/39 1/39 1/39 3/39
48.7 48.7 2.6 2.6 7.7
Fig. 2. Kaplan–Meier plot of target lesion revascularization in patients undergoing laser atherectomy for in-stent restenotic femoropopliteal lesions.
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PATENT which may explain the higher TLR rate in our cohort. The ongoing randomized controlled EXCITE ISR (Randomized Study of Laser and Balloon Angioplasty Versus Balloon Angioplasty to Treat Peripheral In-stent Restenosis) trial will help determine whether ELA with adjunctive PTA is superior to PTA alone. In our study, patients who did not meet the primary endpoint of TLR had a marked improvement in their Rutherford Becker class (Fig. 1) and their ABI (Table 3) that persisted at one year follow up. Survival plot for TLR (Fig. 2) indicates that patients have the highest TLR rate between 100 and 200 days post index procedure followed by a stable period with minimal change in TLR. This may indicate that about half of the patients treated with ELA will have no TLR and will sustain the early benefit gained during the index procedure based on symptoms and ABI. Our study is limited by its observational retrospective design. It is a single arm with no control group and therefore no conclusions can be made about ELA vs. POBA. ELA appears safe, however, with no serious intraprocedural complications. DE has been previously reported with ELA [33–36]. Embolic filter use may be an important step in the procedure to avoid DE [37] particularly in high risk long occlusions and thrombotic lesions. The cost-effectiveness of ELA with EFP needs to be evaluated in future studies. Finally, in this study, no patency data were systematically evaluated and therefore the restenosis rate cannot be accurately assessed. TLR and TVR in this study were clinically driven based on recurrence of symptoms. References [1] Schillinger M, Sabeti S, Loewe C, et al. Balloon angioplasty versus implantation of nitinol stents in the superficial femoral artery. N Engl J Med 2006;354:1879-88. [2] Laird JR, Katzen BT, Scheinert D, et al. Nitinol stent implantation versus balloon angioplasty for lesions in the superficial femoral artery and proximal popliteal artery: twelve-month results from the RESILIENT randomized trial. Circ Cardiovasc Interv 2010;3:267-76. [3] Schillinger M, Sabeti S, Dick P, et al. Sustained benefit at 2 years of primary femoropopliteal stenting compared with balloon angioplasty with optional stenting. Circulation 2007;115:2745-9. [4] Laird JR, Katzen BT, Scheinert D, et al, RESILIENT Investigators. Nitinol stent implantation vs. balloon angioplasty for lesions in the superficial femoral and proximal popliteal arteries of patients with claudication: three-year follow-up from the RESILIENT randomized trial. J Endovasc Ther 2012;19:1-9. [5] Iida O, Nanto S, Uematsu M, et al. Influence of stent fracture on the long-term patency in the femoro-popliteal artery: experience of 4 years. JACC Cardiovasc Interv 2009;2:665-71. [6] Laird JR. Limitations of percutaneous transluminal angioplasty and stenting for the treatment of disease of the superficial femoral and popliteal arteries. J Endovasc Ther 2006;13(Suppl. 2):II30-40. [7] Shammas NW, Shammas GA, Helou TJ, et al. 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. [8] Sixt S, Rastan A, Beschorner U, et al. Acute and long-term outcome of Silverhawk assisted atherectomy for femoro-popliteal lesions according the TASC II classification: a single-center experience. Vasa 2010;39(3):229-36. [9] Zeller T, Rastan A, Sixt S, et al. Long-term results after directional atherectomy of femoro-popliteal lesions. J Am Coll Cardiol 2006;48:1573-8. [10] Dick P, Sabeti S, Mlekush W, et al. Conventional balloon angioplasty versus peripheral cutting balloon angioplasty for treatment of femoropopliteal artery instent restenosis: initial experience. Radiology 2008;248:297-302. [11] Banerjee S, Das TS, Abu-Fadel MS et al. Pilot Trial of Cryoplasty or Conventional Balloon Post-Dilation of Nitinol Stents for Revascularization of Peripheral Arterial Segments: The COBRA Trial. J Am Coll Cardiol 2012. [Epub ahead of print]. http:// www.ncbi.nlm.nih.gov/pubmed/22981558. [12] Dake MD, Scheinert D, Tepe G, et al. Zilver PTX Single-Arm Study Investigators. Nitinol stents with polymer-free paclitaxel coating for lesions in the superficial femoral and popliteal arteries above the knee: twelve-month safety and effectiveness results from the Zilver PTX single-arm clinical study. J Endovasc Ther 2011;18:613-23.
[13] Wissgott C, Kamusella P, Andresen R. Treatment of in-stent reocclusions of femoropopliteal arteries with mechanical rotational catheters. Rofo 2011;183: 939-44. [14] Silingardi R, Cataldi V, Moratto R, et al. Mechanical thrombectomy in in-stent restenosis: preliminary experience at the iliac and femoropopliteal arteries with the Rotarex System. J Cardiovasc Surg (Torino) 2010;51(4):543-50. [15] Yeo KK, Malik U, Laird JR. Outcomes following treatment of femoropopliteal instent restenosis: a single center experience. Catheter Cardiovasc Interv 2011;78: 604-8. [16] Trentmann J, Charalambous N, Djawanscher M, et al. Safety and efficacy of directional atherectomy for the treatment of in-stent restenosis of the femoropopliteal artery. Cardiovasc Surg (Torino) 2010;51:551-60. [17] PATENT trial. Photo-Ablation Using the Turbo-Booster and Excimer Laser for InStent Restenosis Treatment study. Presented at LINC 2012 at the Leipzig Interventional Course, in Leipzig, Germany. Article online in Endovascular today http://www.bmctoday.net/evtoday/2012/01/article.asp?f=interim-resultspresented-for-spectranetics-patent-study. [18] Laird Jr JR, Yeo KK, Rocha-Singh K, et al. Excimer laser with adjunctive balloon angioplasty and heparin-coated self-expanding stent grafts for the treatment of femoropopliteal artery in-stent restenosis: twelve-month results from the SALVAGE study. Catheter Cardiovasc Interv 2012, http://dx.doi.org/10.1002/ccd.23475 [Epub ahead of print]. [19] Pershukov IV, Niiazova-Karben ZA, Batyraliev TA, et al. Effectiveness of excimer laser coronary angioplasty in treatment of patients with in-stent restenosis. Kardiologiia 2003;43:35-44. [20] Karaca I, Ilkay E, Akbulut M, Yavuzkir M. Treatment of in-stent restenosis with excimer laser coronary angioplasty. Jpn Heart J 2003;44:179-86. [21] Dahm JB. Excimer laser coronary angioplasty (ELCA) for diffuse in-stent restenosis: beneficial long-term results after sufficient debulking with a lesionspecific approach using various laser catheters. Lasers Med Sci 2001;16:84-9. [22] Hamburger JN, Foley DP, de Feyter PJ, et al. Six-month outcome after excimer laser coronary angioplasty for diffuse in-stent restenosis in native coronary arteries. Am J Cardiol 2000;86:390-4. [23] Topaz O, Bernardo NL, Shah R, et al. Effectiveness of excimer laser coronary angioplasty in acute myocardial infarction or in unstable angina pectoris. Am J Cardiol 2001;87:849-55. [24] Topaz O, Shah R, Mohanty PK, et al. Application of excimer laser angioplasty in acute myocardial infarction. Laser Surg Med 2001;29:185-92. [25] Topaz O, Minisi AJ, Bernardo NL, et al. Alterations of platelet aggregation kinetics with ultraviolet laser emission: the “stunned platelet” phenomenon. Thromb Haemost 2001;86:1087-93. [26] Dahm JB, Kuon E. High-energy eccentric excimer laser angioplasty for debulking diffuse in-stent restenosis leads to better acute- and 6-month follow-up results. J Invasive Cardiol 2000;12:335-42. [27] Dormandy JA, Rutherford RB. Management of peripheral arterial disease (PAD). TASC Working Group. TransAtlantic Inter-Society Consensus (TASC). J Vasc Surg 2000;31(1 Pt 2):S1–S296. [28] Bosiers M, Deloose K, Callaert J, et al. Results of the Protege EverFlex 200-mm-long nitinol stent (ev3) in TASC C and D femoropopliteal lesions. J Vasc Surg 2011;54: 1042-50. [29] Iida O, Soga Y, Hirano K, et al. Long-term outcomes and risk stratification of patency following nitinol stenting in the femoropopliteal segment: retrospective multicenter analysis. J Endovasc Ther 2011;18:753-61. [30] Iida O, Uematsu M, Soga Y, et al. Timing of the restenosis following nitinol stenting in the superficial femoral artery and the factors associated with early and late restenoses. Catheter Cardiovasc Interv 2011;78:611-7. [31] Trabattoni D, Agrifoglio M, Cappai A, Bartorelli AL. Incidence of stent fractures and patency after femoropopliteal stenting with the nitinol self-expandable SMART stent: a single-center study. J Cardiovasc Med (Hagerstown) 2010;11: 678-82. [32] Tosaka A, Soga Y, Iida O, et al. Classification and clinical impact of restenosis after femoropopliteal stenting. J Am Coll Cardiol 2012;59:16-23. [33] Shammas NW, Coiner D, Shammas GA, et al. Distal embolic event protection using excimer laser ablation in peripheral vascular interventions: results of the DEEP EMBOLI registry. J Endovasc Ther 2009;16:197-202. [34] Rastan A, Sixt S, Schwarzwälder U, et al. Initial experience with directed laser atherectomy using the Clirpath Photoablation Atherectomy System and Bias sheath in superficial femoral artery lesions. J Endovasc Ther 2007;14:365-73. [35] Lam RC, Shah S, Faries PL, et al. 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Contents lists available at SciVerse ScienceDirect
Cardiovascular Revascularization Medicine
Review
Safety and One-Year revascularization outcome of excimer laser ablation therapy in treating in-stent restenosis of femoropopliteal arteries: A retrospective review from a single center☆ Nicolas W. Shammas ⁎, Gail A. Shammas, Alexander Hafez, Ryan Kelly, Emily Reynolds, Andrew N. Shammas Midwest Cardiovascular Research Foundation, Davenport, IA, USA
a r t i c l e
i n f o
Article history: Received 15 July 2012 Received in revised form 30 August 2012 Accepted 31 August 2012 Keywords: Atherectomy In-stent restenosis femoropopliteal segment Excimer Laser long term outcome
a b s t r a c t Background: Treatment of in-stent restenosis of the femoropopliteal (FP) arteries is challenging with a high rate of restenosis. Excimer laser atherectomy (ELA) has a theoretical advantage of ablating restenotic tissue and reducing or delaying the need for repeat revascularization. We present a retrospective analysis from our center on the outcomes of ELA in the treatment of in-stent restenosis of the FP arteries. Methods: Demographic, clinical, angiographic and procedural data were collected on all patients that underwent ELA for in-stent restenosis from February 2005 to April 2010 at a single medical center. Major adverse events and one-year target lesion revascularization (TLR) and target vessel revascularization (TVR) were obtained by reviewing of medical records. Descriptive analysis was performed on all variables. Kaplan– Meier survival curves for TLR were plotted. Results: 40 consecutive patients (mean age 67.7±9.0 years, 57.5% males) were included and followed for 1 year. Adjunctive balloon angioplasty was performed in 100% at a mean pressure of 12.4±2.9 atm. Acute procedural success (b30% angiographic residual narrowing) occurred in 92.5% of patients. Embolic filter protection (EFP) was used in 57.5% of patients. Bailout stenting was 50.0%. Macrodebris was noted in 65.2% of filters. The following adverse events were reported: distal embolization (DE) requiring treatment 2.5% (1 patient with no EFP); planned minor amputation 2.6%, planned major amputation 2.6%, total death 7.7% (all cardiac related). One perforation occurred treated successfully with stenting and balloon inflation. At one year, TLR and TVR occurred in 48.7% and 48.7% respectively. Conclusion: ELA has an overall favorable acute result in treating in-stent restenosis of the FP arteries. At one year TLR and TVR remain clinically significant. DE also occurs significantly with ELA and is effectively prevented with EFP. © 2012 Elsevier Inc. All rights reserved.
1. Introduction Several studies have shown that stenting of the femoropopliteal artery (FP) leads to higher long term patency and less target lesion revascularization (TLR) [1–4]. Stenting however, has several disadvantages including a continued high rate of restenosis and stent fractures [5,6]. Treatment of these in-stent restenotic (ISR) lesions has a high procedural success rate but distal embolization (DE), the need for additional stenting and recurrent restenosis remain prevalent [7– 10]. Several methods have been proposed to treat in-stent FP lesions including plain old balloon angioplasty (POBA) [10], PolarCath ☆ Conflict of Interest: This study is supported by the Nicolas and Gail Research Fund at the Midwest Cardiovascular Research Foundation. No commercial support was provided for this project. Dr NW Shammas does not have any equity or financial interest in any medical device or drug listed in this manuscript. Full COI at www. mcrfmd.com. ⁎ Corresponding author. Cardiovascular Medicine, PC, 1236 E Rusholme, Suite 300, Davenport, IA 52722. Tel.: +1 563 320 0263. E-mail address: [email protected] (N.W. Shammas). 1553-8389/$ – see front matter © 2012 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.carrev.2012.08.012
(Boston Scientific, Natick, Mass) cryoplasty [11], cutting balloons [10], drug-eluting self-expanding stents (Zilver X) (Cook Medical, Bloomington, IN, USA) [12], atherectomy with (Rotarex S) (Staub Medical AG, Wangs, Switzerland) [13,14] or without (SilverHawk) (Covidien, Mansfield, MA) [7–9,15,16] embolectomy, and laser ablation (Excimer laser) (Spectranetics, Colorado Springs, Co, USA) [17] with adjunctive covered stents (Viabahn) (W.L. Gore and Associates, Newark, DE) [18]. Debulking of in-stent restenotic FP lesions have been attempted to reduce restenotic tissue burden and theoretically delay or reduce the rate of repeat revascularization. The off label use of SilverHawk atherectomy (Covidien, Mansfield, MA) in these lesions has been shown to have high procedural success but skills and techniques of the operator are important to avoid complications [7–9]. To our knowledge there are no published randomized data to date on angioplasty versus stenting or debulking (with the SilverHawk or the Excimer laser) of in-stent restenotic FP lesions. Coronary studies have shown that laser effectively ablates restenotic tissue and thrombus, commonly found in occlusive in-stent
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Table 1 Demographics and clinical characteristics. n
mean±SD
Age Body Mass Index Baseline ABI of treated Leg at rest Baseline ABI of treated leg with exercise
40 39 35 25
67.7±9.0 28.9±5.6 0.63±0.2 0.38±0.2
Gender-male Prior percutaneous coronary intervention Prior coronary bypass surgery Previous myocardial infarction Family History Premature CAD Renal Failure (CreatinineN2.0) Chronic obstructive lung disease Hypertension Cerebrovascular disease Hyperlipidemia history of smoking Diabetes Mellitus Onset of symptoms-Subacute Onset of symptoms-chronic Claudicants (Rutherford Becker 1–3) Limb ischemia (Rutherford Becker 4–5)
23/40 22/40 9/40 7/40 14/40 2/40 1/40 34/40 9/40 32/40 33/40 19/40 22/40 16/40 28/38 10/38
Percentage 57.5 55.0 22.5 17.5 35.0 5.0 2.5 85.0 22.5 80.0 82.5 47.5 55.0 40.0 73.7 26.3
ABI=ankle brachial index.
restenosis of FP lesions [19–24]. Excimer laser also suppresses platelet aggregation and therefore potentially reduces the chance of platelet mediated thrombotic reocclusion [25]. Although acute results appear to be satisfactory in ablating restenotic tissue, the long term outcome has been variable and may be related to the extent of tissue debulking [26]. In this study, we evaluate the acute procedural and long term outcome of ISR FP lesions treated with the excimer laser. Secondary endpoints included the safety of the laser within stented segments, bail-out stenting and distal embolization. 2. Methods 457 patients with FP disease were treated by 2 operators at our medical center from February 2005 to April 2010. Patients were included if their index lesions were restenotic, in-stent and were only in the FP arteries. Patients were excluded if they had de novo lesions or non FP segments treated during the index procedure or if they were treated with a non excimer laser atherectomy device. There were no prespecified guidelines to the choice of the device which was based on operator's judgment. Demographics, clinical, procedural and angiographic variables were retrospectively reviewed from a prospective peripheral vascular database developed at our institution. One-year follow up was achieved on all patients by reviewing medical records by a dedicated research coordinator. The study was approved by the Institutional Review Board (IRB). In-hospital and 1-year major adverse events including amputation (major and minor, planned and unplanned), death, vessel perforation, distal embolization (as captured by an embolic filter or distally embolized and requiring further treatment with pharmacologic or mechanical means), major bleeding, myocardial infarction, stroke, access complications, acute renal failure, and acute or subacute vessel closure. Major bleeding was defined as a drop ofN3 gm/dl Hb with a clear source of bleed, retroperitoneal bleed, or intracranial bleed. Acute renal failure was defined as an increase in creatinine within 48–72 h of the procedure byN0.5 mg per dl. The Trans-Atlantic Inter-Society Consensus (TASC I) [27] was used to classify lesion complexity. The primary effectiveness endpoint was acute procedural success defined as obtaining angiographically less than 30% residual narrowing respectively with no serious adverse events at the end of the procedure [7]. Secondary endpoints included acute device success
defined as a residual narrowing ofb50% by the ELA device alone and before adjunctive treatment, DE, clinically driven TLR and TVR at one year based on symptom recurrence, ankle brachial indices (ABI) and Rutherford–Becker class at one month, 6 months and one year in TLRfree patients, death, and amputation. Patients were followed up at approximately 1 month, 6 month and one year intervals in the office. Follow-up ABI testing was not part of a mandatory protocol but was generally done on the majority of patients. Descriptive analysis was done on all variables. Continuous variables were presented as mean±SD and dichotomous variables as percentages. Kaplan–Meier survival curve for TLR was plotted. 3. Results Of 457 FP treated patients, 123 were treated with excimer laser. 83 patients did not meet the inclusion criteria (de novo lesions=67; devices used other than balloon or stent post laser =7; use of balloon or an atherectomy/embolectomy device before laser=2; non-index procedure in patients treated with 2 separate procedures with the laser in the same FP segment =7). 40 patients met the inclusion criteria and formed the cohort of this study. Demographic and clinical variables are presented in Table 1. Patients had multiple comorbidities with a high frequency of hypertension (85.0%), hyperlipidemia (80.0%), smoking history (82.5%) and diabetes (47.5%). The majority of the patients were claudicants (73.7%) and with subacute (b 1 month, N 24 h) (55%) or
Table 2 Angiographic and procedural characteristics.
Number of runoff vessels of treated leg Prestenosis severity (%) Poststenosis severity (%) Lesion length (mm) Lesion diameter (mm) Balloon pressure (mmHg) Laser parameters Fluency (mJ/mm2) Repetitions (Hz) Total Pulses Total laser time (s) Laser catheter size (mm)
n
mean±SD
40 40 40 35 40 39
1.7±1.0 93.9±8.9 14.0±13.0 210.4±104.0 5.6±0.7 12.4±2.9
21 27 24 24 38
56.2±13.6 60.0±20.6 11476±9063 188.6±138.6 2.2±0.3
39/40 40/40 20/40
97.5 100.0 50.0
15/20 2/20 2/10 1/20 13/25 37/40 0/40
75.0 10.0 10.0 5.0 52.0 92.5 0
5/40 16/40 19/40
12.5 40 47.5
30/35 5/35 23/40
85.7 14.3 57.5
6/23 2/23 15/23 1/40
26.1 8.7 65.2 2.5
Percentage Intraprocedural anticoagulant-bivalirudin Adjunctive Balloon use Bailout Stent Reason for Bailout stent N 30% residual N 30% residual and type C or higher dissection Investigator discretion Perforation Device success (b50% residual with laser alone) Procedural success (b30% residual at end of treatment) In-hospital major adverse events TASC type FP-B FP-C FP-D Laser type Elite Booster or tandem Embolic filter use Debris None Microembolization Macroembolization Distal Embolization requiring treatmenta TASC=Trans-Atlantic Inter-Society Consensus. FP=femoropopliteal. a No filter used.
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Table 3 Ankle–Brachial Index and Rutherford Becker class in patients free of target lesion or vessel revascularization at 1 year.
ABI ABI ABI ABI
(baseline) (30 days) (6 months) (1 year)
Median Median Median Median
Rutherford Rutherford Rutherford Rutherford
Becker Becker Becker Becker
(baseline) (30 days) (6 months) (1 year)
n
Mean±SD
17 12 10 8
0.6±0.2 1.0±0.1* 0.9±0.1^ 0.9±0.2#
n
Median
21 22 18 16
3.0 1.0** 0.0^^ 0.5##
Compared to ABI baseline: *p=0.000, ^p=0.003, #p=0.017. Compared to Rutherford Becker baseline: **p=0.002, ^^p=0.000, ##p=0.0002.
chronic symptoms (N 1 month) (40.0%). Angiographic and procedural variables are presented in Table 2. The mean lesion length was 210.4 ± 104.0 mm and 47.5% of lesions were TASC D. Procedural and device successes were achieved in 92.5% and 52.0% of patients respectively. Bail out stenting was performed in 50% of patients. Macroembolization occurred in 65.2% of filters. One patient with DE required additional treatment successfully. Among patients who did not have TLR there was continued stable improvement in ABI and Rutherford Becker class up to one year (Table 3). At one year there were more patients in Rutherford class 0 and 1 than baseline (Fig. 1). Also, compared to baseline, ABI at one month also significantly improved to 1.0±0.1 (p=0.000) and remained stable at one year (0.9±0.2). There were 3 deaths, all cardiac, and 2 unplanned amputations (1 minor and 1 major). TVR and TLR (Fig. 2) were 48.7% and 48.7% respectively (Table 4). There was no major bleeding or acute renal failure. One-year follow up was achieved on 39/40 (97.5%) patients.
4. Discussion In-stent restenosis is a prevalent problem in the FP segment occurring in 19% to 37% of treated lesions at 1 year [1,2,28,29] and up to 49% at 2 years [3]. Predictors of in-stent restenosis in the first year post treatment include female gender, diabetes mellitus, critical limb ischemia, stent fracture and Trans-Atlantic Inter-Society Consensus II C/D lesions [30]. Also lesion length correlates with increased restenosis in treating FP segments [29,31]. Revascularization of FP ISR lesions with stable long term results remains a challenge to the endovascular specialist. Freedom from TLR remains low with POBA (64%) at 6 months even in relatively short ISR lesions [10]. In the COBRA trial [11], binary restenosis with POBA remains high at one year at 55.8% in all lesions and 70% in patients with total occlusions. This is consistent with reported primary patency with POBA of 69% in in-stent stenotic lesions and 23% in in-stent total occlusions [32]. Several methods have been attempted to treat FP ISR with variable success including cutting balloon [10], cryoplasty [11], Zilver PTX self-
Fig. 1. Rutherford Becker class in patients with no target lesion revascularization at baseline, 1 month, 6 months and 1 year after excimer laser treatment.
expanding drug eluting nitinol stent [12], Rotarex S atherectomy [13,14], SilverHawk atherectomy [7–9,15,16] and laser ablation (Excimer laser) with adjunctive covered stents (Viabahn) [18]. There are no published randomized data to evaluate the role of ELA in the treatment of FP ISR lesions. Laird et al. [18] recently reported the results of the SALVAGE trial with the use of the excimer laser and the Viabahn (W.L. Gore and Associates, Newark, DE) covered stent in treating FP ISR. The primary patency at 12 months was measured by duplex ultrasonography. Twenty-seven patients were enrolled. The mean lesion length was 200.7 mm and the majority of lesions were TASC C/D. Procedural success was achieved in 100% of cases. Primary patency and TLR at 12 months were 48% and 17.4% respectively. This prospective single arm registry does not distinguish, however, between the relative effectiveness of the laser versus the Viabahn endograft stent in reducing restenosis in FP ISR lesions. In our study, ELA with or without adjunctive balloon angioplasty or stenting had a TLR of 48.7%. This rate remains significantly high, presumably related to the high prevalence of diabetes, TASC D and very long lesions; all are associated with restenosis in the FP segment [29–31]. The 6-month interim results from the PATENT (PhotoAblation Using the Turbo-Booster and Excimer Laser for In-Stent Restenosis Treatment) study were recently presented [17]. PATENT is a prospective registry evaluating laser atherectomy for treating FP ISR. Data on 78 patients were presented. Mean lesion length was 125 mm and 37% were total occlusions. 50% of these patients were diabetic. At 6 months, TLR rate was 24%. Our registry included significantly longer lesions (200.7 mm vs. 125 mm) and more total occlusions than
Table 4 Long term outcomes of Excimer laser atherectomy. Time to Target lesion revascularization (days)
Target vessel revascularization (%) Target lesion revascularization (%) Planned major amputation (%) Planned minor amputation (%) Death (%)⁎ ⁎ All deaths were cardiac related.
167.0±83.3 n
percentage
19/39 19/39 1/39 1/39 3/39
48.7 48.7 2.6 2.6 7.7
Fig. 2. Kaplan–Meier plot of target lesion revascularization in patients undergoing laser atherectomy for in-stent restenotic femoropopliteal lesions.
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PATENT which may explain the higher TLR rate in our cohort. The ongoing randomized controlled EXCITE ISR (Randomized Study of Laser and Balloon Angioplasty Versus Balloon Angioplasty to Treat Peripheral In-stent Restenosis) trial will help determine whether ELA with adjunctive PTA is superior to PTA alone. In our study, patients who did not meet the primary endpoint of TLR had a marked improvement in their Rutherford Becker class (Fig. 1) and their ABI (Table 3) that persisted at one year follow up. Survival plot for TLR (Fig. 2) indicates that patients have the highest TLR rate between 100 and 200 days post index procedure followed by a stable period with minimal change in TLR. This may indicate that about half of the patients treated with ELA will have no TLR and will sustain the early benefit gained during the index procedure based on symptoms and ABI. Our study is limited by its observational retrospective design. It is a single arm with no control group and therefore no conclusions can be made about ELA vs. POBA. ELA appears safe, however, with no serious intraprocedural complications. DE has been previously reported with ELA [33–36]. Embolic filter use may be an important step in the procedure to avoid DE [37] particularly in high risk long occlusions and thrombotic lesions. The cost-effectiveness of ELA with EFP needs to be evaluated in future studies. Finally, in this study, no patency data were systematically evaluated and therefore the restenosis rate cannot be accurately assessed. TLR and TVR in this study were clinically driven based on recurrence of symptoms. References [1] Schillinger M, Sabeti S, Loewe C, et al. Balloon angioplasty versus implantation of nitinol stents in the superficial femoral artery. N Engl J Med 2006;354:1879-88. [2] Laird JR, Katzen BT, Scheinert D, et al. Nitinol stent implantation versus balloon angioplasty for lesions in the superficial femoral artery and proximal popliteal artery: twelve-month results from the RESILIENT randomized trial. Circ Cardiovasc Interv 2010;3:267-76. [3] Schillinger M, Sabeti S, Dick P, et al. Sustained benefit at 2 years of primary femoropopliteal stenting compared with balloon angioplasty with optional stenting. Circulation 2007;115:2745-9. [4] Laird JR, Katzen BT, Scheinert D, et al, RESILIENT Investigators. Nitinol stent implantation vs. balloon angioplasty for lesions in the superficial femoral and proximal popliteal arteries of patients with claudication: three-year follow-up from the RESILIENT randomized trial. J Endovasc Ther 2012;19:1-9. [5] Iida O, Nanto S, Uematsu M, et al. Influence of stent fracture on the long-term patency in the femoro-popliteal artery: experience of 4 years. JACC Cardiovasc Interv 2009;2:665-71. [6] Laird JR. Limitations of percutaneous transluminal angioplasty and stenting for the treatment of disease of the superficial femoral and popliteal arteries. J Endovasc Ther 2006;13(Suppl. 2):II30-40. [7] Shammas NW, Shammas GA, Helou TJ, et al. 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. [8] Sixt S, Rastan A, Beschorner U, et al. Acute and long-term outcome of Silverhawk assisted atherectomy for femoro-popliteal lesions according the TASC II classification: a single-center experience. Vasa 2010;39(3):229-36. [9] Zeller T, Rastan A, Sixt S, et al. Long-term results after directional atherectomy of femoro-popliteal lesions. J Am Coll Cardiol 2006;48:1573-8. [10] Dick P, Sabeti S, Mlekush W, et al. Conventional balloon angioplasty versus peripheral cutting balloon angioplasty for treatment of femoropopliteal artery instent restenosis: initial experience. Radiology 2008;248:297-302. [11] Banerjee S, Das TS, Abu-Fadel MS et al. Pilot Trial of Cryoplasty or Conventional Balloon Post-Dilation of Nitinol Stents for Revascularization of Peripheral Arterial Segments: The COBRA Trial. J Am Coll Cardiol 2012. [Epub ahead of print]. http:// www.ncbi.nlm.nih.gov/pubmed/22981558. [12] Dake MD, Scheinert D, Tepe G, et al. Zilver PTX Single-Arm Study Investigators. Nitinol stents with polymer-free paclitaxel coating for lesions in the superficial femoral and popliteal arteries above the knee: twelve-month safety and effectiveness results from the Zilver PTX single-arm clinical study. J Endovasc Ther 2011;18:613-23.
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