Comparison of the OUTBACK® Elite Reentry Catheter and the Bi-directional Approach after Failed Antegrade Approach for Femoro-popliteal Occlusive Disease.

AIM: A successful antegrade wire crossing for femoro-popliteal chronic total occlusion (FP-CTO) is still a technical challenge. We attempted to demonstrate the safety and feasibility of the OUTBACK® Elite reentry catheter and the bi-directional approach for failed FP-CTO cases with the antegrade approach. METHODS: Endovascular therapy for FP-CTO was performed in 219 lesions from May 2013 to December 2016 at Morinomiya Hospital. We retrospectively analyzed the data of 43 consecutive lesions which underwent endovascular therapy using the bi-directional approach with distal access and the mono-directional approach with the OUTBACK® Elite reentry catheter for FP-CTO lesions. The antegrade success using a combination of traditional and Intravascular Ultrasound (IVUS) -guided techniques was achieved in 170 lesions out of a total of 219 lesions. From May 2013 to June 2016 (phase 1), the bi-directional approach with distal access was applied to 22 lesions after failed antegrade approaches. From July 2016 to December 2016 (phase 2), the mono-directional approach with the OUTBACK® Elite reentry catheter was applied to 21 lesions. RESULTS: Clinical and lesion characteristics in phase 1 were not significantly different from those in phase 2. The overall initial technical success rate was 100% in both phases. The total wire number and amount of contrast media were significantly less, and the total procedure time and the total fluoroscopic time were significantly shorter in phase 2 than in phase 1 (p＜0.01). CONCLUSIONS: Endovascular therapy for FP-CTO using the OUTBACK® Elite reentry catheter is feasible and safe after a failed antegrade approach.

Wire Passages of 0.035-inch Looped Wire Technique for Femoropopliteal Long Total Occlusions.

AIM: Although it is understood that a looped wire technique using a 0.035-inch wire for femoropopliteal (FP) long chronic total occlusions (CTOs) goes to the subintima, there has been no systematic assessment of wire passages. The purpose of this study is to examine these passages by intravascular ultrasound (IVUS) after looped wire technique for FP long CTOs. METHODS: Between March 2012 and October 2014, 57 consecutive FP long CTO lesions (mean lesion length, 246 ± 42 mm), involving the superficial femoral artery ostium and treated with IVUS-guided endovascular therapy, were enrolled. After IVUS confirmed that the initial wire passage was intraplaque, the looped wire technique was routinely conducted through the CTO body. Based on IVUS findings, the wire passage was classified into 3 types: intraplaque, subintimal, and intramedia. RESULTS: At the FP lesion in the proximal, middle, and distal segments, the wire proceeded intraplaque in 98%, 25%, and 20% cases; subintimal in 2%, 61%, and 52%; and intramedia in 0%, 14%, and 28%, respectively. The success rate of antegrade wiring was 74%, with the remaining 26% cases requiring an additional retrograde approach. CONCLUSIONS: The looped wire technique variably proceeds to intraplaque, subintimal, or intramedia, even starting from intraplaque in FP long CTOs.

Real chimney technique for total debranching of supra-aortic trunks.

Side-clamping of the ascending aorta is an indispensable technique for proximal anastomosis in total debranching of supra-aortic trunks and in endovascular aneurysm repair for arch aneurysm. However, this procedure may lead to the dislodging of multiple plaques and to clamp injury of the ascending aorta. We developed a clampless technique to achieve proximal anastomosis between the ascending aorta and an artificial graft used for total debranching of supra-aortic trunks. We applied this method in six patients with arch aneurysm and a plaque-rich ascending aorta and were able to achieve total debranching of the supra-aortic trunks in all of the patients without side-clamping the ascending aorta and no procedurally related complications. This clampless anastomosis technique ("real chimney technique") in the ascending aorta is a valuable option for total debranching of supra-aortic trunks in the hybrid repair of arch aneurysms.

Spinal cord injury after endovascular treatment for thoracoabdominal aneurysm or dissection.

OBJECTIVES: Postoperative spinal cord injury (SCI) is a devastating complication of surgical repair for thoracoabdominal aortic aneurysm or dissection (TAAD), despite the complex reconstruction of inter-costal or lumbar arteries involved in the surgery. As an alternative technique, endovascular thoracoabdominal aneurysm repair (EVTAR) with visceral artery reconstruction has been accepted as a treatment option for severe comorbid patients of TAAD, because there is a permissible frequency of SCI after EVTAR in spite of no reconstruction of inter-costal or lumbar arteries. We report the results of EVTAR at our hospital with a focus on spinal cord injury. METHODS: We analyzed data from 54 consecutive patients with TAAD (mean age, 74 ± 9.6 years; 42 men) who underwent EVTAR at our hospital between February 2007 and February 2014. Three types of EVTAR technique were used: fenestrated and/or branched stent graft implantation in 39 patients, a hybrid technique (bypass grafts to visceral arteries and straight stent graft implantation) in 10 patients, and intentional coverage of the coeliac artery and straight stent graft implantation in 5 patients. In all patients, mean systemic blood pressure was maintained at ≥80 mmHg. Opioid use was avoided in the perioperative period. RESULTS: According to the Crawford classification, the graft coverage extent was 9% (5/54) in type I, 11% (6/54) in type II, 39% (21/54) in type III, 22%(12/54) in type IV and 19% (10/54) in type V. In most patients (74%, 40/54), cerebrospinal fluid drainage was done intraoperatively and 1 day postoperatively. Hospital mortality was 5.6% (3/54). No patient developed SCI in the perioperative period. However, in the follow-up period 2 patients developed paraplegia as a consequence of shock caused by an aortic event. CONCLUSIONS: With close attention to spinal cord protection, EVTAR may be associated with only a low incidence of SCI in the perioperative period. Therefore, EVTAR is expected to become a promising treatment option for appropriately selected patients with TAAD.

Safety and efficacy of carbon dioxide and intravascular ultrasound-guided stenting for renal artery stenosis in patients with chronic renal insufficiency.

We evaluated the feasibility, safety, and mid-term outcomes of renal artery stenting using carbon dioxide (CO2) digital subtraction angiography and intravascular ultrasound (IVUS) for patients with renal insufficiency and significant atherosclerotic renal artery stenosis (RAS). Eighteen consecutive patients with chronic renal insufficiency underwent renal artery stenting under the guidance of CO2 angiography and IVUS without contrast media. Renal function and blood pressure were assessed pre- and postintervention. A total of 27 de novo RAS in 18 patients (15 males; mean age: 72 ± 9 years) with renal insufficiency were treated by renal artery stenting with the combined use of the CO2 angiography and IVUS without any procedural complications. Although the mean serum creatinine concentration preprocedure and 6 months after treatment did not change (2.7 ± 1.0-2.4 ± 1.1 mg/dL), blood pressure significantly decreased 6 months after stenting (158 ± 10-147 ± 11 mm Hg, P < .01).

Feasibility of endovascular abdominal aortic aneurysm repair outside of the instructions for use and morphological changes at 3 years after the procedure.

INTRODUCTION: We retrospectively analyzed outcomes of patients who had undergone endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA) more than 3 years previously in a single institution. We compared outcomes between patients who underwent EVAR within and outside of the devices' instructions for use (IFU) and examined mid-term morphological changes in AAA. METHODS: A total of 275 patients who underwent EVAR for AAA were selected. IFU parameters included aneurysmal neck length, angulation and presence of massive atheroma. Patients were divided into 2 groups: the Within IFU group (W-IFU: n = 193) and the Outside of IFU group (O-IFU: n = 82). RESULTS: Patients in the O-IFU group were older and had a larger AAA diameter. Other comorbid factors were similar between the 2 groups. There was no difference in overall survival rates and reintervention rates between the 2 groups. The most common cause for reintervention was AAA enlargement 3 years after EVAR. Irrespective of the IFU, mid-term morphological changes, including neck angulation, neck diameter, sac re-expansion, and Palmaz stent displacement, were found. CONCLUSION: Outcomes of EVAR were considered acceptable in the O-IFU group. Careful follow-up is necessary considering the morphological changes in AAAs after EVAR.

Study Design of PROCEDURE Study. A Randomized Comparison of the Dose-Dependent Effects of Pitavastatin in Patients with Abdominal Aortic Aneurysm with Massive Aortic Atheroma: Prevention of Cholesterol Embolization during Endovascular and Open Aneurysm Repair with Pitavastatin (PROCEDURE) Study.

Outcomes of abdominal aortic aneurysm (AAA) repair have improved in the 2 decades since the emergence of endovascular aneurysm repair (EVAR). However, EVAR is considered a contraindication for shaggy aorta because of the high risk of shower embolization. Recently, statins have been implicated in preventing embolization in patients with shaggy aorta via its pleiotropic effects, including atheroma reduction and coronary artery stabilization. We selected pitavastatin, a statin with potent effects, discovered and developed by a Japanese company because it has shown excellent pleiotropic effects on atheromatous arteries in the Japanese population. A randomized comparison study of dose-dependent effects of pitavastatin in patients with AAA with massive atheromatous aortic thrombus (PROCEDURE study) has begun. PROCEDURE has an enrollment goal of up to 80 patients with AAA with massive aortic atheroma (excluding intrasac atheroma), randomly allocated into 2 groups receiving pitavastatin at a dose of 1 or 4 mg/day. The endpoints of the PROCEDURE study include change in atheroma volume, major adverse events related to shower embolization after aneurysm repair, and lipid-lowering effects. When complete, results of the PROCEDURE study should provide objective evidence to use statins preoperatively for AAA with massive aortic atheroma.

Successful endovascular repair in two cases of graft limb occlusion after endovascular aneurysm repair for abdominal aortic aneurysms.

Among 148 abdominal aortic aneurysm patients who underwent endovascular aneurysm repair at our institution, two cases of graft limb occlusion (GLO) were identified and successfully treated with endovascular repair. Guidewire cannulation against the occluded limb is the most important aspect of the procedure. After a thrombectomy, balloon dilatation is performed followed by stent-graft deployment. Various procedures such as thrombectomy, thrombolysis, and extra-anatomical bypass have been adopted for the treatment of GLO. Our use of endovascular techniques, including overlapping stent grafts, has some benefits, namely, better patency of anatomical route revascularization, decreased risk of ipsilateral shower embolization due to the stent graft's sealing over the irregular remnant thrombus, and easy access to angioplasty for tortured iliac arteries. However, shower embolization during catheter handling or future fabric failure due to friction is the potential complication associated with endovascular techniques. Intravascular repair techniques and stentgraft use should therefore be an early step of the GLO treatment algorithm.