Percutaneous Laser-Facilitated Thrombectomy: An Innovative, Easily Applied, and Effective Therapeutic Option for Recanalization of Acute and Subacute Thrombotic Hemodialysis Shunt Occlusions

Cool Excimer Laser-Assisted Angioplasty vs. Percutaneous Transluminal Angioplasty for Infrapopliteal Arterial Occlusion: A Meta-Analysis and Systematic Review

Background

Percutaneous transluminal angioplasty (PTA) has been the conventional therapy to infrapopliteal arterial occlusion. Lately, cool excimer laser-assisted angioplasty has been proposed to be the alternate methods. We performed a systematic review and meta-analysis of prospective and retrospective cohort studies and randomized controlled trials to assess the effect of cool excimer laser-assisted angioplasty vs. tibial balloon angioplasty in patients with infrapopliteal arterial occlusion.

Methods and Results

We systematically searched PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL) (all up to April, 2021). All prospective and retrospective cohort studies and randomized controlled trials comparing clinical outcomes between cool excimer laser-assisted angioplasty and tibial balloon angioplasty were included. The main endpoints were amputation-free survival (AFS), primary patency (6 months and 12 months) and free from target lesion revascularization (TLR) (3 years). Secondary outcomes included the major amputation (1 year), dissection, embolization and bailout stent. We chose the effect model according to studies' heterogeneity. A total of 122 articles were found. According to inclusion criteria, 6 papers were finally selected for the detailed evaluation. Of the 6 papers, 4 were prospective cohort studies, and 2 were retrospective studies. Compared with PTA, CELA significantly increased the rate of patency (6 months: MD 13.01, 95% CI 3.12-22.90, P < 0.05; 12 months: MD 11.88 95% CI 8.38-15.37, P < 0.05) and the rate freedom from TLR (36 months: MD 7.51 95% CI 0.63-14.40, P < 0.05). There is no statistically difference of AFS, major amputation, dissection, embolization and bailout stent between CELA group and PTA group (MD −2.82, 95% CI −8.86-3.22, P = 0.36; MD −0.17, 95% CI −1.04-0.70, P = 0.39; MD 1.11, 95% CI 0.58-2.10, P = 0.75; MD 0.46, 95% CI 0.11-1.99, P = 0.30; MD 1.89, 95% CI 0.92-3.88, P = 0.09).

Conclusions

CELA had superior clinical (freedom from TLR) and angiographic outcomes (patency rate) for infrapopliteal arterial occlusion at the same time CELA does not have increased intervention-related complications compared to PTA. However, CELA is unable to improve the patient's limb salvage rate compared with PTA.

Safety and efficacy of the AngioJet device in the treatment of thrombosed arteriovenous fistula and grafts: A systematic review

PURPOSE

The AngioJet Hemolytic Thrombectomy Device "AngioJet" (Boston Scientific, Malborough, MA, USA) is a rheolytic thrombectomy device that can be used in the treatment of hemodialysis arteriovenous fistula and graft thrombosis. We aim to appraise the current evidence on AngioJet thrombectomy in hemodialysis vascular access thrombosis, and to determine its safety, including complications and efficacy.

MATERIALS AND METHODS

An electronic literature search was performed on the MEDLINE and Embase databases. References of retrieved articles were also reviewed. Articles using AngioJet for the treatment of arteriovenous fistula or graft were included. Patients less than 18 years old, non-English articles, single case reports, small case series (<5 cases), conference publications, and nonhuman models were excluded.

RESULTS

A total of 688 articles were initially evaluated and 10 articles fulfilled the inclusion criteria, which included 836 patients with 431 grafts and 234 fistulas. Results were heterogeneously reported. The adjusted mean primary patency rates for 1, 3, 6, and 12 months were 64.6%, 43.8%, 42.5%, and 30.5%, respectively; adjusted mean secondary patency rates for 3, 6, and 12 months were 76.5%, 75.1%, and 74.5%, and assisted primary patency rates were 61.9%, 47.3%, and 35.3%, respectively. There were 126 complications, most were minor. There were seven deaths, but were unable to be attributable to the AngioJet.

CONCLUSION

The AngioJet is an effective and safe treatment option for thrombosed fistulas and grafts. However, the quality of the current evidence is poor. Further research with prospective randomized controlled trials using standardized data reporting methods is needed to prove its safety and efficacy.

Current Endovascular Management of Acute Limb Ischemia

Acute limb ischemia is a vascular emergency, threatening the viability of the affected limb and requiring immediate recognition and treatment. Even with revascularization of the affected extremity, acute limb ischemia is associated with significant morbidity and mortality resulting in up to a 15% risk of amputation during the initial hospitalization and a 1 in 5 risk of mortality within 1 year of the index event. This review summarizes the current management of acute limb ischemia. Understanding the diagnosis and therapeutic options will aid clinicians in treating these critically ill patients.

Recanalization of thrombosed arteriovenous fistulas for hemodialysis by minimal venotomy

The present work describes the preliminary results of a new method of minimally invasive thrombectomy in the treatment of thrombosed arteriovenous fistula (AVF) with dilated aneurysm. Data from 25 patients who were treated with this minimal venotomy technique were retrospectively reviewed. The minimal venotomy was made on the dilated fistula, and thrombectomy was performed with forceps and Fogarty catheters through the venotomy site. Technical and clinical success was achieved in all 25 patients. There were two major and two minor complications (8% each). The two major complications consisted of bleeding at the venotomy site after early suture removal.

Treatment of subacute and chronic thrombotic occlusions of lower extremity peripheral arteries with the excimer laser: a feasibility study

BACKGROUND

Thrombus is highly prevalent in patients with recent symptoms (< 6 months) of claudication or limb ischemia due to an occluded culprit lower extremity vessels. Treatment of these thrombotic occlusions is challenging. In this feasibility study, the excimer laser (Spectranetics, Colorado Springs, CO) has been tested for its safety and ability to ablate thrombus in patients with recent arterial occlusions.

METHODS

Angiographic operator assessment and volumetric core lab quantitation of the thrombus were performed at baseline and after excimer laser but prior to definitive treatment of the vessel to evaluate thrombus resolution. Consecutive patients were prospectively enrolled at a single site. Procedural success was defined as achieving a residual stenosis of <30% after final treatment with no intraprocedural complications requiring additional treatment.

RESULTS

20 consecutive patients were enrolled in this study (8 males, mean age 69.5±11.1 years). Based on patients symptom onset, 12 patients were subacute (> 24 h, < 30 days), and 8 chronic (between 1 to 6 months). 15/20 (75%) had restenotic occlusions. Due to the long, occlusive nature of these lesions, only 8 patients had complete intravascular ultrasound images at each time point which allowed volumetric analysis by the core lab. There was no statistical difference in plaque/thrombus volume between baseline (pretreatment) and excimer laser (P=.68). There was however a significant reduction in residual angiographic stenosis post laser alone (100% vs. 66.75%±23.9%, P=.001). Procedural success was 100%. There were no deaths or amputations. Bail out stenting was performed in 10/20 (50%) patients. Embolic filters were used in 15/20 (75%) of patients. Macrodebris>2 mm were seen in 85.7% of filters. There was no in-hospital or 30-day reocclusion of the treated vessel but one patient had a vascular access complication (small AV fistula) conservatively managed. No other serious adverse events were noted.

CONCLUSION

Using the excimer laser appears safe in this small feasibility study of subacute and chronic thrombotic occlusions. Angiographically, there was a significant reduction in percent stenosis with the laser alone. The limited IVUS data did not show a reduction in plaque/thrombus volume but the number of interpretable ultrasounds was small. Further data are needed to address the effectiveness of the laser in treating these thrombotic occlusions and its advantages over balloon angioplasty.

Sonography characteristics of the intra-graft thrombus: association with procedure success and procedure time of percutaneous transluminal angioplasty for thrombosed prosthetic dialysis graft

Percutaneous transluminal angioplasty (PTA) for thrombosed dialysis graft is both difficult and time-consuming that may increase radiation exposure. A predictor of PTA success and procedure time has not been identified yet. Sonography data and the PTA results of 88 grafts were reviewed retrospectively. The echogenicity of the majority of the intra-graft thrombus and the presence/absence of thrombus free space in the grafts were examined. The association between the sonography findings and PTA procedure success and procedure time was analyzed. The echogenicity of the intra-graft thrombus and presence/absence of thrombus free space were the major determinants of procedure success and procedure time. Higher intra-graft echogenicity and lack of thrombus free space were associated with more procedure failures (p < 0.01 vs. p = 0.04) and longer procedure times (p = 0.03 vs. p < 0.01). Thrombi from occluded dialysis grafts may differ in resistance to mechanical/pharmacological thrombolysis. Sonography characteristics of the intra-graft thrombus may help to differentiate them.

Surgical aspects and biological considerations of arteriovenous fistula placement

Since the Fistula First Initiative was formulated in 2003, providers and payers have increasingly emphasized the need to create more arteriovenous fistulae. To maximize the chances of successful fistula maturation, a thorough understanding of the biology and surgical aspects of fistula placement are essential. A functional endothelium in the target vessels is the prerequisite for the adaptive remodeling of the vessel wall, which has to take place after fistula formation. Mechanoreceptors of the endothelium sense the increase in shear stress and, through a variety of activated signaling cascades, induce the necessary changes and vasodilation of the respective vessels. The successful fistula placement starts with a thorough preoperative evaluation, which focuses on protecting the target vessels and avoiding intravenous catheters and devices. Intraoperatively, the risk of endothelial dysfunction and hyperplasia is further minimized through an atraumatic dissection with minimal manipulation of the vein and artery. The surgical technique should also focus on decreasing the vessel compliance mismatch and avoiding an inflammatory response secondary to hematoma formation. Postoperatively, the fistula must be diligently monitored for the complications of thrombosis, postoperative steal syndrome, neuropathy, aneurysm formation, infection, and high-output cardiac failure. Early recognition of a problem is the key to saving an otherwise doomed fistula. An armamentarium of percutaneous techniques is available to the access surgeon to treat the most common causes of failed access formation. However, in some cases a surgical revision of the access site through patch angioplasty, a jump graft, and graft interposition is necessary to create a fistula which can be successfully used for hemodialysis.

Mid-term results with laser atherectomy in the treatment of infrainguinal occlusive disease

BACKGROUND

Laser atherectomy offers a potential intervention for multivessel infrainguinal disease in patients with poor revascularization options. Despite promising early results reported in the literature, the proper patient population who might benefit from laser atherectomy has yet to be determined.

METHODS

From July 2004 to June 2006, patients undergoing laser atherectomy were retrospectively reviewed and assessed for comorbidities, operative and follow-up variables potentially associated with the end points of nondefinitive therapy, and limb salvage.

RESULTS

During the study period, 40 patients (21 women, 19 men) underwent laser atherectomy, and the average follow-up was 461 +/- 49 days (range, 17 to 1050 days). Their average age was 68 +/- 2 years (range, 43 to 93 years). The indication for laser atherectomy was critical limb ischemia in 26 (65%) and lower limb claudication in 11 (35%). A total of 47 lesions were treated in the following arterial segments: 34 femoropopliteal and 13 infrapopliteal. Femoropopliteal distribution by the Trans-Atlantic Society Classification (TASC) was A in 3, B in 17, C in 10, D in 4, and infrapopliteal lesions distribution was A in 1, B in 3, C in 4, and D in 5. Adjunctive angioplasty was used in 75% of cases. The overall technical success rate (<50% residual stenosis) was 88%. Laser atherectomy-based treatment was the definitive therapy for 23 patients (58%), and the overall 12-month primary patency was 44%. The limb salvage rate at 12 months in 26 patients with critical limb ischemia was 55%. Renal failure was a risk factor for amputation (P < .001) and failed primary patency (P < .05), type 2 diabetes mellitus was a risk factor for amputation (P < .05), and poor tibial runoff was associated with failed primary patency and amputation (P < .05). Outcome was associated with the number of patent infrapopliteal runoff vessels.

CONCLUSION

These data demonstrate that laser atherectomy can be used with high initial technical success rate. Chronic renal failure and diabetes are risk factors for a negative outcome. Poor results in patients with diabetes and renal failure necessitate careful case selection in this subgroup, in which laser atherectomy is less likely to provide a definitive revascularization result or limb salvage.