Peripheral Chronic Total Occlusions Research Articles

Ocelot catheter for the recanalization of lower extremity arterial chronic total occlusion

Peripheral arterial disease (PAD) is a growing clinical condition affecting more than 10 million patients in the United States and it is responsible for more than 120,000 amputations annually. The presence of chronic total occlusions (CTO) increases the complexity of endovascular procedures and open surgery may often be the preferred approach. Despite the optimization of the CTO devices and technique, percutaneous CTO revascularization remains a challenging procedure even for experienced operators with important complication rates. The Ocelot(TM) system is a novel CTO device to use real-time optical coherence tomography (OCT) imaging guidance for the recanalization of peripheral CTOs. We review the mechanism of the Ocelot system, the initial results from the multi-center Connect-II trial and two cases of Ocelot-assisted CTO recanalization.

Pioneer re‐entry device for iliac chronic total occlusion: Truly a Paradigm shift

The number of percutaneous revascularization procedures performed for symptomatic peripheral arterial disease has significantly increased over the past several years. Traditionally, the use of percutaneous techniques were limited to certain anatomic subsets, such as stenosis or focal occlusions, with surgical treatment preferred for more extensive disease. More recently, endovascular specialists are facing the challenge of peripheral chronic total occlusions. Furthermore, unlike the coronary circulation, these occlusions are often very long and associated with other features of complexity such as severe calcifications. One of the primary issues concerning these lesions is the ability to safely achieve initial angiographic success. This article focus indeed on the Pioneer catheter, a new lumen re-entry device exploiting intravascular ultrasound imaging that was used in a case of totally occluded left common iliac artery with favorable results. The details of this technique, and how this catheter helped in re-entering the true lumen at the aortic bifurcation after subintimal dissection, are thoroughly discussed.

Subintimal angioplasty with a true reentry device for treatment of chronic total occlusion of the arteries of the lower extremity

To report the efficacy and safety of the Outback(®) LTD(®) Re-Entry Catheter in reentering the distal true lumen during percutaneous intentional extraluminal revascularization (PIER). Reentry catheters are used to treat chronic, total arterial occlusions of the lower extremities when standard methods of recanalization have failed. Success and complication rates of these catheters in the real world are uncertain and variable. A retrospective review of our peripheral catheterization database from January 2004 to September 2009 was undertaken to identify consecutive cases of peripheral chronic total occlusions (CTOs) requiring the use of the Outback reentry catheter. Patient demographics, indication for the procedure, location and extent of occlusion, procedural success, and complications were studied. A total of 51 patients were identified. Of the 51, 28 (54.9%) patients presented with nonhealing ulcer and 22 (43.1%) had lifestyle-limiting claudication. One patient presented with acute limb ischemia. There were 6 (11.8%) patients with common iliac artery occlusion, 2 (3.9%) with external iliac artery occlusion, 1 (1.9%) with common femoral artery occlusion, 35 (68.6%) with superficial femoral artery occlusion, 6 (11.8%) with popliteal artery occlusion, and 1 (1.9%) with tibioperoneal artery occlusion. Median lesion length was 230 mm. Procedural success was achieved in 49 patients (96.1%). There was 1 (1.9%) periprocedural complication. Use of Outback(®) LTD(®) Re-Entry Catheter is a safe and valuable option for PIER/subintimal angioplasty and recanalization in patients with symptomatic lower-extremity CTOs. However, long-term patency remains unknown.

A case of successful use of microsnare to hold and pull the retrograde guidewire for the intervention to peripheral chronic total occlusion

A basket-shaped microsnare has various uses such as the pull through technique during coronary intervention to chronic total occlusion (CTO). A 79-year-old man underwent angioplasty for the femoral artery occlusion. We performed a controlled antegrade and retrograde tracking (CART) with dilatation of a balloon on the antegrade guidewire. The retrograde guidewire partly ran in the true lumen but could not pass through the CTO lesion because of inadequate CART. Eventually, we successfully gripped the top of the retrograde guidewire in the CTO lesion using the basket-shaped microsnare (Soutenir(®)). The microsnare may be useful for bidirectional approach in peripheral CTO lesions.

A successful retrograde re‐entry at aorta using the outback LTD catheter for a bilateral common iliac artery occlusion

The Outback LTD re-entry catheter system has become a valuable tool for peripheral intervention and it has been widely used for variable peripheral chronic total occlusion (CTO). However, its use in the setting of the aorta was restricted because of concerns of bleeding risks resulting from re-entry puncture or ballooning. This report presents a case of successful re-entry using the Outback LTD Re-Entry Catheter (Cordis, Bridgewater, New Jersy) at the aorta in a patient with bilateral common iliac artery occlusion.

Devices to Treat Peripheral Chronic Total Occlusions

Chronic total occlusions occur in approximately 40% of patients with peripheral vascular disease and are a difficult lesion subset to treat by endovascular approaches. The challenge lies in the difficulty in placing a wire across the site of occlusion and remaining in an intraluminal position. Conventional percutaneous transluminal balloon angioplasty for chronic total occlusions involves advancing a stiff wire through the site of obstruction, has the chance for vessel dissection and perforation, and is associated with high rates of procedural failure. Several mechanical devices have thus been developed to treat peripheral chronic total occlusions. In this article, we provide a review of the currently available devices that may increase the procedural success of treating peripheral chronic total occlusions.

Recanalization of Femoropopliteal Chronic Total Occlusions Using the ENABLER-P Balloon Catheter System

To evaluate the safety and effectiveness of a new system to facilitate intraluminal advancement of conventional guidewires through chronic total occlusions (CTO) of the superficial femoral artery (SFA) and popliteal artery. The ENABLER-P Balloon Catheter System uses a unique balloon-anchoring mechanism and an automated balloon inflation device for steady, controlled advancement of a standard non-hydrophilic guidewire. The system was evaluated in 37 patients (22 men; mean age 67 years (range 41-87) with femoropopliteal CTOs averaging 86 mm in length (range 10-340). The device was used in a variety of occlusions, including heavily calcified, long, and fibrotic lesions. After successful guidewire recanalization facilitated by the system, occluded arterial segments were treated conventionally with balloon angioplasty, atherectomy, and stents as appropriate. The primary endpoint of successful crossing was achieved in 86% (32/37) of the overall study population. The average activation time for successful crossing was 5.3 minutes (range 0.4-22). Of the 32 cases successfully crossed with the ENABLER-P System, all but 1 was successfully recanalized. One (3%) device-related complication occurred when the wire was advanced into a side branch when treating a 300-mm-long flush ostial SFA occlusion; the resulting perforation was managed with a covered stent without further sequelae. This novel system, which provides enhanced force to a standard guidewire tip for controlled intraluminal advancement, is a promising device for the treatment of peripheral CTOs.

Endovascular sharp recanalization for calcified femoropopliteal artery occlusion.

Endovascular intervention of peripheral chronic total occlusion (CTO) is technically challenging and time consuming. Various techniques and devices are used to facilitate lesion crossing and improve the success rate of the procedure. However, these new devices are quite expensive and not readily available. We report 2 cases of peripheral CTO wherein the occlusions were successfully crossed by using stiff end of Terumo glidewire. This sharp recanalization may be a useful technique for the recanalization of calcified peripheral CTOs when conventional techniques fail and new devices are not readily available, but it is accompanied by the risk of distal atheroembolism.

Retrograde access via the popliteal artery to facilitate the re‐entry technique for recalcitrant superficial femoral artery Chronic total occlusions

Subintimal recanalization is beneficial in selected patients with peripheral chronic total occlusions (CTO). However, in complex cases, re-entry into the true arterial lumen may prove to be unsuccessful with a conventional guidewire or a re-entry catheter when using standard femoral artery access. Our case series describes these technical dilemmas along with strategies that can be utilized to overcome these challenges.

Re-canalization of Peripheral Chronic Total Occlusions Using the BridgePoint Stingray Re-entry Device

Percutaneous intervention of peripheral chronic total occlusions (CTO) is increasingly common, but Interventionalists still face significant barriers to successful treatment of CTO lesions in the coronary and peripheral anatomy. The greatest overall challenges are in crossing the CTO lesion and re-entering the true lumen from a successful subintimal crossing. We present a case report of a patient with a CTO of a lower extremity artery, in which treatment with a new, novel system was used to address both of these challenges.

Novel high-frequency vibration approach for recanalization of difficult coronary and peripheral chronic total occlusions

Chronic total occlusions (CTOs) continue to be quite prevalent and still present as some of the most challenging lesions for the coronary and/or peripheral interventionalist. Recanalization success rates have been historically low and the potential for adverse events are typically higher than the more common procedures of angioplasty and stenting. At present, there are two paths to successful CTO recanalization; the subintimal approach and the central lumen approach. The subintimal approach tracks a standard guidewire around the occlusion and through the subintimal plane, while the luminal approach attempts to recanalize the occlusion through the central lumen of the artery. After failure to stay in the true lumen, a bypass is essentially created around the occlusion through the adventitia. This may lead to adverse events. A central luminal approach may provide increased safety and more therapeutic options to the clinician and may ultimately deliver enhanced longer-term outcomes owing to the optimization ...

A novel catheter in patients with peripheral chronic total occlusions: A single center experience

Recanalization of a chronic total occlusion (CTO) is technically challenging with less than optimum results in arterial disease. Crosser® is a novel technology that utilizes high frequency (20 KHz) vibration energy to fragment occlusive fibrous atherosclerotic plaque and helps in traversing the occluded vessel. We report a single center experience with this catheter as the primary device in peripheral chronic total occlusions. The catheter was used as the primary device in 25 consecutive patients with peripheral CTOs. The peripheral CTOs in this study are defined as 100% occluded vessels involving any segment of the iliac artery or below the inguinal ligament down to the trifurcation vessels which have been occluded for greater than 3 months judged by patient's history of longstanding symptoms with no worsening in the past 3 months. Procedural success was defined by the ability of the device to facilitate guide wire crossing of the occlusion. All angiograms were evaluated by two operators. Data on demographics, angiographic variables, and patient complications was collected. The device was used in 25 consecutive patients and 27 CTO lesions were treated. Critical limb ischemia and claudication were the indications in 32 and 68% of the patients, respectively. Average lesion length was 117 mm (range 10-300 mm). Superficial femoral artery was the most common lesion site (n = 20, 74%). Crosser-assisted guide wire recanalization was achieved in 11(41%) lesions while the final overall procedure success rate with any device was 63% (n = 17). Perforation occurred in five lesions with one directly attributable to this device. In this single center observational review, the Crosser device in peripheral CTO lesions had a procedural success of 41%. © 2010 Wiley-Liss, Inc.

Use of high‐frequency vibrational energy in the treatment of peripheral chronic total occlusions

Peripheral chronic total occlusions (CTO) are challenging lesions to treat. The CROSSER system (FlowCardia, Sunnyvale, CA) uses high-frequency low-amplitude vibrations to break through the cap of the CTO and had been shown to be successful in coronary CTOs. This is a case series demonstrating the use of the CROSSER system with peripheral CTOs. Three patients with peripheral CTO of various lengths, locations, and complexities were treated with the CROSSER system. The device allowed placement of a guidewire across the area of occlusion, thus permitting further percutaneous intervention. The CROSSER system was effective with both ostial and distal lesions, tapered and abrupt lesion morphologies, and was used from both an ipsilateral (antegrade access) and contralateral approach. The CROSSER system is an additional device that may be used to treat peripheral CTOs.

Novel use of ultrasound guidance for recanalization of iliac, femoral, and popliteal arteries

We attempted to demonstrate the safety and feasibility of intravascular ultrasound (IVUS)-guided endluminal endovascular therapy for chronic total occlusion (CTO) of the iliac and/or femoropopliteal arteries using Treasure 12, a stiff guidewire for peripheral CTO of 0.018 in. in monodirectional approach setting. Endovascular therapy for CTO of the iliac and femoropopliteal arteries is still technically challenging. Endovascular therapy was performed in 110 patients who were admitted to Hyogo College of Medicine Hospital with iliac and/or femoropopliteal artery disease from January 2006 to October 2007. We retrospectively analyzed the data of consecutive 47 patients who underwent the endovascular therapy by monodirectional approach for CTO lesions of the iliac and femoropopliteal arteries. From January 2006 to November 2006 (phase 1), standard technique was applied for the treatment of 21 lesions. From December 2006 to October 2007 (phase 2), IVUS-guided endovascular therapy was applied for the treatment of 31 lesions. Clinical and lesion characteristics in phase 1 were not significantly different from those in phase 2. The overall initial technical success rate improved from 81% in phase 1 to 97% in phase 2. There were no significant differences in radiation exposure time between phase 1 and phase 2. Total volume of contrast material was significantly smaller in phase 2 than in phase 1 (P < 0.01). The IVUS-guided endovascular therapy for CTO using Treasure 12 guidewire is feasible and safe, minimizes contrast material, and has a high initial technical success rate.

Ex vivo imaging of chronic total occlusions using forward‐looking optical coherence tomography

Percutaneous coronary interventions (PCI) of chronic total occlusions (CTOs) of arteries are more challenging lesions to treat with angioplasty and stenting than stenotic vessels due primarily to the difficulty in guiding the wire across the lesion. Angiography alone is unable to differentiate between the occluded lumen and the vessel wall and to characterize the content of the occlusion. New technologies to aid in interventional guidance are therefore highly desirable. We sought to evaluate tissue characterization in arterial (CTOs) by imaging ex vivo peripheral arterial samples with optical coherence tomography (OCT). Ex vivo arterial samples were obtained from patients undergoing peripheral limb amputation. Samples were imaged in an enface orientation using an OCT system, enabling sequential acquisition of longitudinal images and volumetric reconstruction of cross-sectional views of the occluded arteries. Histology was performed for comparison. OCT imaging reliably differentiated between the occluded lumen and the underlying arterial wall in peripheral CTOs. OCT correctly identified tissue composition within the CTO, such as the presence of collagen and calcium and was also able to identify intraluminal microchannels. OCT imaging of CTO anatomy and tissue characteristics may potentially lead to substantial improvements in PCI interventions by providing novel guiding capabilities.

Controlled blunt microdissection for percutaneous recanalization of lower limb arterial chronic total occlusions: A single center experience

Percutaneous techniques for the revascularization of symptomatic lower limb arterial chronic total occlusions (CTOs) remain suboptimal due to difficulty in safely and reliably crossing these heavily calcified lesions using standard guidewire and balloon technology. The objective of this prospective study was to evaluate the technical success and safety of controlled blunt microdissection (CMD) for the treatment of resistant peripheral CTOs. This series enrolled 36 patients (26 men; mean age 67 +/- 12 years), with 44 symptomatic CTOs (2 terminal aortic, 24 iliac, 16 femoral, and 2 popliteal), which had previously failed conventional percutaneous revascularization. CMD was carried out using a specialized prototype catheter. Actuation of the hinged jaws of this CMD catheter created a channel within the occluded arterial segment for guidewire passage, and subsequent angioplasty and stenting using standard procedures. The problem of subintimal CMD catheter passage, creating an eccentric channel, was addressed using a second novel device, the true-lumen reentry (LRE) catheter, which allowed reentry into the downstream lumen. Procedural success, evaluated angiographically, was achieved in 40 (91%) of the 44 CTOs. Fourteen (35%) of these 40 successful recanalizations required guidewire redirection, using the LRE catheter for lesion traversal. There were no complications related to CMD per se; although one patient experienced acute in-stent thrombosis, managed successfully with intra-arterial thrombolysis. We therefore conclude that CMD can be used safely and successfully to facilitate recanalization of resistant CTOs in the pelvic and lower limb arteries.

Percutaneous bypass: subintimal recanalization of peripheral occlusive disease with IVUS guided luminal re-entry

Angioplasty of chronic total occlusions (CTOs) has lower technical success rates with longer procedure times and poorer outcomes. Subintimal recanalization remains limited by the lack of controlled re-entry into the true lumen of the target vessel. We report our experience using a commercially available catheter-based system equipped with an intravascular ultrasound scanner to achieve controlled true lumen re-entry in patients with peripheral CTOs. In a 4-month period, 6 patients with lower extremity (LE) ischemia from CTOs were treated. Occluded segments were crossed subintimally, and controlled re-entry was secured using the CrossPoint TransAccess catheter. This 6.2 F dual-lumen catheter contains an integrated 64-element phased array intravascular ultrasound scanner enabling targeting of structures. Intravascular ultrasound-guided luminal re-entry was achieved by advancing a 24-gauge needle to a desired length and delivering a 0.014” guide wire into the target lumen. The occluded segments were balloon dilated and stented using self-expanding nitinol stents. Effective luminal re-entry and re-establishment of antegrade flow occurred in all 6 patients. Time to recanalization ranged from 5 to 10 minutes. All patients were free of ischemic symptoms at 1 to 5 month follow-up. There were no procedure-related complications. Our preliminary results demonstrate the feasibility of using this catheter system for subintimal recanalization with controlled re-entry in CTOs. This approach can improve the technical success rate, reduce the time of the procedure, and minimize potential complications.