Crossing of Infrainguinal Peripheral Arterial Chronic Total Occlusion With a Blunt Microdissection Catheter

Abstract: Purpose. Crossing of lower-extremity arterial chronic total occlusion (CTO) can be challenging. Use of the Viance peripheral CTO crossing device (Covidien) in the superficial femoral (SFA), popliteal, and below-the knee (BTK) arterial locations has received limited study. Methods. Fifty-eight patients from the Excellence in Peripheral Artery Disease (XLPAD) registry (NCT01904851) were treated between April 2010 and November 2013 with the Viance device. The procedural and 30-day clinical outcomes were collected. Results. Mean age was 65.5 ± 8.7 years and 55.1% had diabetes mellitus. Most lesions (n = 58) were TASC classification type C (n = 16; 27.6%) and D (n = 16; 27.6%), with mean lesion length 140.0 ± 71.0 mm; 93.1% of lesions were de novo and 81.0% were severely calcified. Technical success (crossing without the use of a reentry device) was achieved in 87.9% of cases and procedural success was obtained in 86.2%; 51.7% of lesions received stents, with the remaining treated with balloon angioplasty and/or atherectomy. Average fluoroscopy time was 39.1 ± 21.2 min, with 187.8 ± 72.0 mL of contrast and 210.0 ± 212.0 Gy cm² radiation dose-area product. There was 1 periprocedural complication (access-site hematoma treated conservatively without blood transfusion). At 30 days post procedure, there was significant improvement in ankle-brachial index (0.72 ± 0.30 to 0.84 ± 0.16; P=.01) and Rutherford class (3.33 ± 0.81 to 1.54 ± 1.47; P<.001). Clinically-indicated target vessel revascularization, surgical intervention or amputation at 30 days was 5.2%. Conclusion. Use of Viance to cross infrainguinal arterial CTO was associated with high success, low complication rates, and significant symptom improvement.

J INVASIVE CARDIOL 2014;26(8):363-369

Key words: peripheral artery disease, infrainguinal artery disease, diabetes mellitus, peripheral arterial CTO, Viance catheter

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In patients undergoing endovascular treatment of infrainguinal peripheral arteries, a chronic total occlusion (CTO) is present in nearly 50% of all angiograms performed.¹ Crossing and reentry of infrainguinal CTO in patients presenting with claudication or critical limb ischemia (CLI) is often challenging and accounts for most procedural failures. Viance (Covidien) is a peripheral arterial CTO crossing blunt microdissection device that has recently been approved for clinical use. Herein, we report technical success, procedural success, and periprocedural complications in a cohort of patients with superficial femoral (SFA), popliteal, and below-the knee (BTK) arterial CTO lesions crossed with the Viance catheter (Covidien), along with a description of the device features, key aspects of optimal handling, and limitations. 

Methods

We evaluated the technical success, procedural success, and 30-day major adverse event (MAE) rate associated with the use of the Viance device in infrainguinal peripheral arteries of patients included in the Excellence in Peripheral Artery Disease (XLPAD) registry (NCT01904851) and referred for clinically indicated endovascular treatment of peripheral arterial disease (PAD) between April 2010 and November 2013. The Viance catheter was formerly known as BigBoss (device name under Bridgepoint).

Patients. Patient demographics, risk factors, comorbidities, laboratory data, medications, and procedural information were derived from the XLPAD registry, patient electronic medical records, and procedural notes. Angiographic data regarding lesion length and lesion characteristics were obtained from the analysis of diagnostic and procedural angiograms performed at the VA North Texas Angiography and Ultrasound Core Laboratory. CTO length was defined as angiographic distance between the proximal and distal caps, and lesion length additionally included any angiographic ≥70% diameter stenosis compared to the reference vessel segment. A single CTO was defined by angiographic 100% occlusion or sequential occlusions separated by ≤2 cm in the SFA and popliteal arteries or a single occlusion separated by ≤1 cm in BTK arterial vessels. Vascular calcification was classified as the presence of either isolated foci of calcification (mild), contiguous segments of calcification on one or alternating sides of the vessel (moderate), or contiguous calcification on both sides of the vessel (severe) visible on angiographic views prior to contrast injection.²

Endpoints. Technical success was defined as placement of a guidewire beyond the distal CTO cap into the true lumen, confirmed by angiographic contrast injection into the distal vessel or by intravascular ultrasound (IVUS). Procedural success was defined as successful revascularization of the CTO with a <30% residual stenosis. All crossing attempts with the Viance catheter were made either as an initial approach or following an unsuccessful attempt with a guidewire to either penetrate the proximal cap of the CTO and/or advance through half of the occluded segment. Technical failure was defined as the need for a reentry device, eg, when Viance was used as the first crossing strategy, switching to a wire-catheter or another crossing device or to a second Viance catheter. All cases involved a retrograde arterial access through the contralateral common femoral artery and placement of a 45 cm, 6-7 Fr vascular sheath. Adjunctive pharmacotherapy with antithrombin and antiplatelet drugs was at the discretion of the operator, as was the decision to perform balloon dilation, atherectomy, and/or stenting. Procedural safety was assessed by MAE reported at 30 days post procedure, and was defined as occurrence of any of the following: all-cause death, target vessel revascularization, need for endovascular or surgical intervention, or unplanned amputation.

Device description. The Viance catheter consists of a multiwire, coiled 2.3 Fr shaft and a 3 Fr rounded atraumatic tip. The shaft is 135 cm long, and is an over-the-wire system compatible with any 0.014˝ guidewire (Figures 1A and 1B). The catheter is advanced to the proximal CTO cap and manually spun using the torqueable handle. When combined with a forward push, this “fast spin technique” allows the device to pass through the CTO via the true lumen or along a subintimal course (Figure 1C). The Viance microdissection catheter is generally advanced over a 0.014˝ guidewire, with an angulated tip to navigate the engaging tip away from a side branch at the proximal CTO stump. The device is advanced through the CTO as described above with the guidewire retracted proximal to the tip.

Statistical analysis. Continuous parameters were reported as mean ± standard deviation, and discrete parameters as percentages. Continuous parameters were compared with one-way ANOVA or the Wilcoxon rank-sum test, and discrete parameters compared with the Pearson chi-square test of the Fisher’s exact test, as appropriate. Time to repeat revascularization procedure was calculated using the Kaplan-Meier method. All analyses were performed with SAS 9.1 (SAS Institute) and SPSS 14.0 for Windows. 

Results

During the study period, there were 58 patients and a total of 58 CTO lesions treated in the SFA, popliteal, and BTK regions treated with Viance. Most patients (93.1%) were men, with a mean age of 65.5 ± 8.7 years and 94.8% of the patients had Rutherford category ≥3 symptoms. The baseline clinical characteristics are shown in Table 1. The majority of the lesions were in the SFA (n = 34; 58.6%), followed by BTK (n = 18; 31.0%) and popliteal (n = 6; 10.3%) arteries; 93.1% of lesions were de novo, 6.9% were in-stent restenotic, and 81.0% were severely calcified. The average CTO length was 132 ± 78.0 mm (range, 20-310 mm) and average total lesion length was 140.0 ± 71.0 mm (range, 20-312 mm). The TransAtlantic Inter-Society Consensus (TASC) class of infrainguinal lesions of type C and D represented 55.2% of the total lesions, while 43.1% were TASC type B.

Procedural details are shown in Table 2. Technical success with the Viance was achieved in 87.9% and overall procedural success was achieved in 86.2% of cases. Following an initial unsuccessful guidewire attempt (n = 10), technical success with the Viance was 50.0% compared to 95.8% with an initial Viance crossing attempt (n = 48; P<.001). There were 7 cases (12.1%) in which the Viance entered the subintimal space and a reentry device was used. Reentry was successful with the Enteer reentry device (Covidien) in 5 cases (71.4%) to gain true lumen access. In 8 cases (14.3%), a >30% residual stenosis was present at the end of the procedure. In 24.1% of the lesions, intravascular ultrasound (IVUS) was used to confirm a distal target vessel true lumen access; in 41.6% of cases, a true lumen course through the entire CTO segment was present. After successfully crossing the CTO, 51.7% of the lesions were stented, and the remaining were treated with balloon angioplasty and/or atherectomy. The mean stent length was 118.8 ± 38.0 mm, with a mean diameter of 5.87 ± 0.67 mm. Mean fluoroscopy duration was 39.1 ± 21.2 min, mean procedure duration was 132.0 ± 51.0 min, and mean contrast use was 187.8 ± 72.0 mL. 

Immediately after the procedure, 1 patient developed an access-site hematoma (5.0 cm in maximum diameter) that was treated with manual compression and observation. At 30 days, there were 3 MAEs (5.2%). Two patients (3.5%) underwent repeat revascularization of the target limb and 1 patient (1.7 %) underwent surgical revascularization. Overall, 3 patients (5.2%) underwent elective revascularization of the opposite leg, and 1 patient (1.7%) was readmitted for acute urinary retention. There were no recorded deaths. There was significant improvement in ankle-brachial index (0.72 ± 0.30 to 0.84 ± 0.16; P=.01) and Rutherford class (3.33 ± 0.81 to 1.54 ± 1.47; P<.001).

Discussion

Our study is the first published multicenter experience with the Viance peripheral arterial CTO crossing device for crossing infrainguinal CTO in patients with symptomatic PAD. Viance use was associated with high technical success, significant improvement in symptoms, and low rates of postprocedural complications and 30-day MAE in a technically challenging lesion subset.

CTOs are frequently encountered during endovascular intervention of infrainguinal PAD. In diabetics, CTO can constitute up to 55% of all infrainguinal arterial lesions in patients with Rutherford category ≥3 symptoms.³ Crossing of these lesions with traditional guidewires can often be challenging and this has prompted the development of several crossing devices, which have been approved for clinical use in the United States. Key predictors of failure to cross an infrainguinal arterial vessel CTO are included in Table 3. Failure to penetrate the proximal cap, navigate side branches or bridging collaterals, and reenter the distal true lumen are a few of the more important mechanisms of failure.⁴ The dense fibrous caps and heavy calcification that often characterize peripheral arterial CTO have been associated with failure to cross.⁵ 

Use of Viance in a diverse subset of infrainguinal CTO by multiple operators, along with a careful analysis of procedural information and core laboratory adjudicated data, provides useful insights regarding the best-practice technique and clinical situations for deployment of this device. Figure 2 depicts a proposed approach to Viance handling in infrainguinal arterial CTO based on the experience of operators participating in the XLPAD registry. The Viance blunt microdissection catheter can be delivered to the proximal CTO cap over any 0.014˝, 300 cm guidewire, but the Confianza PRO 12 0.014˝ guidewire (Abbott Vascular) is preferred due to superior support. The Confianza Pro 12 wire retains the angulated tip shape after being advanced through the Viance catheter, and does not interact with the Viance lumen, to limit guidewire manipulation. The angulated tip is often required to direct the device away from a side branch at the proximal CTO stump. The guidewire can be placed at variable distances from the tip, (ideally 15-20 mm), and this allows adjustment of the device tip strength and penetrating ability. For hard to penetrate proximal CTO caps, the guidewire should be advanced to the tip of the device. In the absence of a side branch, the blunt tip of the device is allowed to engage the lesion. The adjustable steering handle should then be moved over the Viance shaft to about 20 mm from its entry into the vascular sheath. The steering handle is used to employ a mechanical spin, together with a gentle forward pressure to advance the device through an occluded vascular segment. The low-profile rotating tip of the device effectuates microdissection through the lesion and requires a two-handed “fast spin” technique. In difficult to advance lesions, it is recommended that the operator put greater emphasis on advancing the guidewire to the device tip and fast spin, rather than exert increased forward pressure on the device. Figure 3 illustrates SFA, popliteal, and peroneal arterial CTO crossings with Viance.

Viance creates a limited channel along its course and therefore can be retracted and redirected. Further, its low profile creates a very limited size subintimal dissection space, which facilitates successful reentry into the distal true lumen with the help of a reentry device. Given its low profile, the flat-shaped reentry balloon catheter (Enteer) is often used in conjunction with Viance. Other reentry devices like the Outback (Cordis Endovascular) and Pioneer (Medtronic) may also be used for true lumen reentry.

Often, CTO crossing devices are deployed following failure of traditional guidewire and guide catheter crossing attempts. As in our study, the technical success of CTO crossing devices after a failed wire-catheter crossing can be limited.⁶ Provisional use of CTO crossing devices after failed wire-catheter crossing needs to be carefully studied and was the primary endpoint of the Peripheral Facilitated Antegrade Steering Technique in Chronic Total Occlusions (PFAST) CTO pivotal study that led to the approval of the Viance (formerly, BigBoss) device.⁷ The results of this study remain unpublished at the time of this manuscript submission. Sixty-six patients (47 men; mean age, 67.8 ± 11.3 years) with CTO of the infrainguinal arteries were enrolled and treated at 9 investigational sites in the United States. Mean CTO lesion length was 19.5 ± 10.8 cm. The catheter was introduced into all patients; in 45 cases, it was the only part of the system used for treatment. In the remaining 21 cases, reentry was attempted distal to the CTO with the Enteer reentry system. Overall technical success was achieved in 85% (56/66). This included success in 84% of cases (38/45), in which only the BigBoss catheter was used and in 86% (18/21) of cases requiring reentry with the Enteer system. MAEs were observed in 2 patients (3.0%) over 30 days. These data are highly relevant to endovascular operators as a majority of these devices (76.0%) are used by operators provisionally, after an unsuccessful initial guidewire crossing attempt.⁸ The question regarding a first-line or provisional use of CTO crossing devices for infrainguinal arterial CTO needs to be studied.

Most of the currently available data come from single-arm device-approval studies, and do not provide comparative assessment to either a wire-catheter or other crossing devices. The Wildcat catheter (Avinger, Inc) with manually rotating wedges on the distal tip was studied as part of the Chronic Total Occlusion Crossing with the Wildcat Catheter (CONNECT) trial. In this trial, 84 infrainguinal CTO lesions (mean length, 174 ± 96 mm) were treated with the Wildcat device after an initial unsuccessful guidewire attempt. Procedural success was 89% and a reentry device was used in 20% of cases.⁹ A study reported a 91% success with the Frontrunner XP (Cordis Endovascular) after an initial guidewire attempt was unsuccessful, resulting in iliofemoral arteries with mean lesion length of 95.0 ± 70.0 mm.¹⁰ The Frontrunner XP device use was reported in 22 patients with prior guidewire failure during crossing of predominantly SFA CTO with 95.5% success by Shetty et al.¹¹ The Crosser device (Flow-Cardia) selectively fragments only the fibrous and calcified segments of a CTO with high-frequency vibrational energy.¹² A recent study reported 76.7% technical success in crossing peripheral arterial CTO without the need of a reentry device.¹³ Lesion length was 131.0 ± 89.0 mm, and all lesions had an entry stump, amenable to Crosser tip engagement. The Safe-Cross wire (Intraluminal Therapeutics), utilizes reflected infrared light source to generate audiovisual guidance for the interventionist based on type of tissue encountered by the guidewire.¹⁴ In a single-center study, this device was associated with 100% success rate in crossing long peripheral arterial CTO segments (224.0 ± 140.0 mm) after an initial failure using a traditional guidewire-catheter approach.¹⁵ Enabler (EndoCross) is another CTO crossing device that uses anchoring balloon for controlled advancement of a guidewire. As the initial method of crossing femoropopliteal lesions (average length, 86.0 mm), it was associated with 86.0% success.¹⁶ 

The results of our study include lesion lengths, lesion characteristics, and patient features similar to the aforementioned studies, and represents the experience of multiple CTO operators, with independent adjudication. Despite a nearly 88.0% technical success rate, these results should be considered exploratory as they include a selection bias and do not provide a comparative assessment to other CTO crossing strategies. The 7 failed crossings with Viance were primarily associated with creation of large subintimal tracts created by prior wire-catheter attempts (n = 5) and due to presence of heavy calcification in the proximal/ostial SFA locations (n = 2). An important aspect of this study is the relatively high rate of successful crossing with primary use of the device (primary technical success), without the need for reentry devices. Many of the prior published studies provide mixed information regarding technical success of the crossing device, because they include successful reentry. We have clearly defined technical success as successful crossing without the need for a reentry device. 

The Viance device, given its low profile, manual control, and 0.014˝ guidewire compatibility, is particularly suited for multi-level infrainguinal CTO. It remained in the true lumen along the entire course of a CTO, as confirmed by IVUS in nearly 40.0% of cases in our study. This can be particularly advantageous in crossing distal SFA, popliteal, and BTK CTOs. A true lumen passage of the Viance device provides options to pursue non-stent treatments like atherectomy with or without balloon angioplasty. The smaller stent length compared to the CTO and lesion lengths treated in our study are attributed to lower need for stenting in distal SFA, popliteal, and BTK locations by virtue of true lumen passage of the device. Although a tactical advantage during the CTO intervention, the impact of this strategy on clinical outcomes, cost, procedure duration, and radiation exposure remains to be determined and should be addressed in future studies. The use of IVUS to determine true lumen passage of CTO crossing devices, and its impact on subsequent treatment options and clinical outcomes, also remains to be determined. 

Study limitations. Although our study provides important technical guidance on the use of the Viance peripheral CTO crossing device, it has important limitations. As stated earlier, it is observational and subject to selection bias. The sample size is small, all lesions are infrainguinal, and follow-up duration is limited. Limitations with respect to technical handling of the device clearly exist, especially with steering the device, in flush or “no-stump” peripheral CTO lesions. Given its low profile, the device may also have limited success in heavily calcified vessels. Clearly, randomized peripheral arterial CTO studies are needed in the future.

Conclusion

Overall, this report indicates that the Viance crossing device provides a safe and effective option for crossing peripheral arterial CTOs.

References

1. Nadal LL, Cynamon J, Lipsitz EC, Bolla A. “Sub-intimal Angioplasty for Chronic Total Occlusions.” Techniques in Vascular and Interventional Radiology. 2004; 7(1):16-22.
2. Mintz GS, Popma JJ, Pichard AD, et al. Patterns of calcification in coronary artery disease. A statistical analysis of intravascular ultrasound and coronary angiography in 1155 lesions. Circulation. 1995;91(7):1959-1965.
3. Aziz S, Ramsdale DR. Chronic total-occlusions – a stiff challenge requiring a major breakthrough: is there light at the end of the tunnel? Heart. 2005;91(3):42-48.
4. Lee HJ, Park SW, Chang IS, et al. Strategies for successful percutaneous revascularization of chronic total occlusion for the femoropoliteal arteries when the antegrade passage of a guidewire fails. Korean J Radiol. 2012;13(4):467-475.
5. Kandzari, David E. The new challenges of chronic total coronary occlusions: an old problem in a new perspective. J Intervent Cardiol. 2004;17(4):259-267.
6. Banerjee S, Sarode K, Mohammad A, et al. Endovascular treatment of infra-inguinal peripheral arterial chronic total occlusions with the TruePath device: featured case series, device features, handling, and procedural outcomes. J Endovasc Ther (in press).
7. Werner GS. The BridgePoint devices to facilitate recanalization of chronic total coronary occlusions through controlled subintimal reentry. Expert Rev Med Dev. 2011;8(1):23-39.
8. Banerjee S, Sarode K, Mohammad A, et al. Multicenter Registry for Peripheral Arterial Disease Interventions and Outcomes (XLPAD Registry) (abstr). J Am Coll Cardiol. TCT Abstract Supplement, 2013.
9. Pigott JP, Raja ML, Davis T. A multicenter experience evaluating chronic total occlusion crossing with the WILDCAT catheter (the CONNECT study). J Vasc Surg. 2012;56(6):1615-1621.
10. Mossop P, Amukotuwa SA, Whitbourn RJ. Controlled blunt microdissection for percutaneous recanalization of lower limb arterial chronic total occlusions: a single center experience. Catheter Cardiovasc Interv. 2006;68(2):304-310.
11. Shetty R, G. Vivek, Thakkar A, et al. Safety and efficacy of the Frontrunner XP catheter for recanalization of chronic total occlusion of the femoropopliteal arteries. J Invasive Cardiol. 2013;25(7):344-347.
12. Gandini R, Volpi T, Pipitone V, et al. Intraluminal recanalization of long infrainguinal chronic total occlusions using the Crosser system. J Endovasc Ther. 2009;16(1):23-27.
13. Staniloae CS, Mody KP, Yadav SS, et al. Endoluminal treatment of peripheral chronic total occlusions using the Crosser recanalization catheter. J Invasive Cardiol. 2011;23(9):359-362.
14. Baim DS, Braden G, Heuser R, et al. Utility of the Safe-Cross guided radiofrequency total occlusion crossing system in chronic coronary total occlusions (results from the Guided Radio Frequency Energy Ablation of Total Occlusions Registry Study). Am J Cardiol. 2004;94(7):853-858.
15. Kirvaitis R, Parr L, Kelly LM, et al. Recanalization of chronic total peripheral arterial Occlusions Using Optical Coherent Reflectometry with Guided Radiofrequency Energy: a single center experience. Catheter Cardiovasc Interv. 2007;69(4):532-540.
16. Zeller T, Kambara AM, Moriera SM, et al. Recanalization of femoropopliteal chronic total occlusions using the ENABLER-P balloon catheter system. J Endovasc Ther. 2012;19(2):131-139.

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From the ¹University of Texas Southwestern Medical Center, Dallas, Texas; ²Veteran Affairs North Texas Healthcare System, Dallas, Texas; ³University of Texas Health Science Center San Antonio, San Antonio, Texas; ⁴Seton Heart Institute, Austin, Texas; ⁵Ball Memorial Hospital, Muncie, Indiana; ⁶St. Louis Veteran Affairs Medical Center, St. Louis, Missouri; ⁷University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma; and ⁸Midwest Cardiovascular Research Foundation, Davenport, Iowa.

Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. Disclosures: Dr Banerjee reports research grants from Boston Scientific, Medicines Company; consultant/speaker for Gilead, St. Jude, Cordis, Boehringer Ingerheim, Sanofi, and Medtronic; ownership in Mdcare Global (spouse); Intellectual property in HygeiaTel. Dr Thomas reports no disclosures. Karan Sarode reports no disclosures. Dr Mohammad reports no disclosures. Dr Sethi reports no disclosures. Dr Baig reports no disclosures. Dr Gigliotti reports speaker income from Janssen; research contracts with Abbott Vascular, Medtronic, and AstraZeneca. Dr Ishti Ali reports lecture fees for Boston Scientific and consultant fees for Merit Medical. Dr Klein reports no disclosures. Dr Abu-Fadel reports speaker income from Abbott Vascular. Dr Shammas reports research grants from Boston Scientific, Possis, the Medicines Company, Abbott Vascular, AGA, Astellas, AstraZeneca, Boehringer Ingelheim, Cordis, ev3, Gilead, Lilly, Pfizer, BMS, Terumo, Zoll LifeVest; speaker income from the Medicines Company, BMS, Sanofi-Aventis, GSK, and Edwards; consultant for CSI, the Medicines Company, ev3, NAMSA; promotional income from Boehringer Ingerheim; Forest Pharmaceuticals; Lilly/Daichii, AstraZeneca, Pfizer/BMS, Gilead. Dr Prasad reports speaker fees from AstraZeneca; consultant for St. Jude Medical Center. Dr Brilakis reports honoraria/speaker fees for Sanofi, Janssen, St. Jude Medical, Terumo, Asahi, Abbott Vascular, Boston Scientific; research grant from Guerbet; spouse employee of Medtronic.

Manuscript submitted January 6, 2014, provisional acceptance given March 18, 2014, final version accepted April 3, 2014.

Address for correspondence: Subhash Banerjee, MD, 4500 S Lancaster Road (111A), Dallas, TX 75216. Email: subhash.banerjee@va.gov