Laser Uses in Noncoronary Arterial Disease

Comparison of the Snare Loop Technique and the Hungaroring Reinforcement for Physician-Modified Endograft Fenestrations-An In Vitro Study

BACKGROUND

We conducted an in vitro comparison of the snare loop reinforcement against a closed-loop reinforcement (Hungaroring) for physician-modified endograft (PMEG) fenestrations regarding preparation time and stability during flaring balloon dilatation.

MATERIALS AND METHODS

The time to complete a PMEG fenestration with reinforcement was measured and compared between the Hungaroring and snare loop groups. The number of stitches was counted. Each fenestration was dilated using a 10 mm high-pressure, non-compliant balloon up to 21 atm in pressure, and fluoroscopic images were taken. The presence of indentation on the oversized balloon at the level of the reinforcement was evaluated at each fenestration.

RESULTS

Five fenestrations were created in each group (n = 5) for a total of ten pieces. The completion time in the snare loop group was 1070 s (IQR:1010-1090) compared to 760 s (IQR:685-784) in the Hungaroring group (p = 0.008). Faster completion time was achieved by faster stitching (23.2 s/stitch (IQR 22.8-27.3) for the snare loop group and 17.3 s/stitch (IQR 17.3-20.1) for the Hungaroring group (p = 0.016). None of the fluoroscopic images of the snare loop reinforcement showed an indentation on the balloon during the overexpansion; on the contrary, the Hungaroring showed indentation in every case, even at 21 atm.

CONCLUSION

Fenestrations reinforced with Hungaroring can be completed significantly faster. Furthermore, the Hungaroring resists over-dilation even at high pressures, while snare loop reinforcements dilate at nominal pressure.

Mechanical Performance Assessment of Physician Modified Aortic Stent Graft

OBJECTIVE

This study aimed to compare various fenestration configurations of physician modified aortic stent grafts in order to identify which design parameters have a significant influence on the mechanical behaviour of the fenestration.

METHODS

the fenestration configurations were considered according to different manufacturing parameters: cutting technique, fenestration reinforcement, suture material, reinforcement loop design, and number of suture points. The performance of the graft/bridging stent assembly was assessed at various levels: (1) branch pull out force; (2) fenestration enlargement and rupture strength; (3) balloon angioplasty resistance; and (4) behaviour under cyclic fatigue.

RESULTS

Sixty manual fenestrations were created. The tests performed on the fenestrations had several main findings. First, reinforcement increased the radial force on the branch, which increased the pull out force; this may limit migration of the bridging stent in vivo. The phenomenon was amplified with a snare reinforced fenestration, which seemed to be the most efficient. Moreover, increasing the number of suture passes also appeared to increase the branch extraction force securing the assembly. The enlargement tests showed that non-reinforced fenestrations had the weakest radial strength. This was confirmed with the balloon angioplasty test, which showed that these latter specimens undergo the most significant textile degradation. After fatigue tests, all fenestrations were larger, showing that elastic recoil was incomplete in all samples. The largest recoil was observed in the non-reinforced ophthalmological cautery (OC) fenestrations (40%). Regarding the behaviour of the samples up to rupture, all samples behaved in a similar way; however, the double loop fenestration strength level was the highest.

CONCLUSION

This study demonstrated that the snare double loop reinforcement has an advantage regarding durability of the graft branch assembly. Moreover, non-reinforced fenestrations show signs of weakness and lack of stability, which questions the in situ or laser fenestration procedures.

Excimer laser atherectomy combined with drug-coated balloon angioplasty for the treatment of femoropopliteal arteriosclerosis obliterans

INTRODUCTION

It has been reported that excimer laser atherectomy combined with a drug-coated balloon (ELA+DCB) can achieve better results than simple balloon angioplasty, especially for the treatment of femoropopliteal in-stent restenosis. However, reports on the application of ELA+DCB in China for femoropopliteal arteriosclerosis obliterans are lacking. This study focuses on analysing the effectiveness and safety of ELA+DCB.

METHODS

This was a single-centre retrospective study that enrolled patients from November 2016 to January 2019 who had femoropopliteal arteriosclerosis obliterans treated by ELA+DCB. Preoperative demographics, operative details and postoperative follow-up outcomes were analysed statistically.

RESULTS

There were 43 patients with an average patient age of 68.0±8.6 years; 79.1% were male. In 30 cases, the lesions were de novo and the others were in-stent restenosis (ISR). During the procedure, flow-limiting dissection (48.8%) was the main adverse event and there were 17 bailout stent implantations due to dissection. Mean (±sd) ankle-brachial index (ABI) in the patients was 0.42±0.31 before the operation and 0.83±0.13 before discharge. The mean (±sd) follow-up time was 29.35±9.71 months. The primary patency rate was 66.8%, 64.3% and 60.9% at 12, 24 and 36 months. Freedom from target lesion revascularisation (TLR) was 85.7%, 80.7% and 75.3% at 12, 24 and 36 months. Rutherford categories also greatly improved during follow-up. Overall mortality was 6.9% (3/48), and no deaths were related to the intervention.

CONCLUSION

The use of ELA+DCB had good clinical benefit for femoropopliteal arteriosclerosis obliterans, which had good primary patency and freedom from TLR, although intraoperative complications still required attention. Multicentre randomised controlled trials with long-term follow-up are needed.

A novel integrated angioscope-laser system for atherosclerotic carotid artery occlusion: Feasibility and techniques

Introduction

Atherosclerotic extracranial carotid artery stenosis accounts for about 20%-30% of all strokes, which is one of the leading causes of adult morbidity and mortality. Although carotid endarterectomy (CEA) is still the mainly operational manner for atherosclerotic carotid artery stenosis/occlusion (ACAS/ACAO), and carotid angioplasty and stenting (CAS) have been used as an alternative, both CEA and CAS have limitations of their own, such as extensive invasiveness and in-stent restenosis.

Methods

In this study we established a novel interventional system in vitro to take advantage of both CEA and CAS. Twenty consecutive carotid atherosclerotic plaques were harvested from the patients who underwent CEA. The plaques were randomized into two groups and inserted into the pruned and sutured descending aortas of the swine in vitro. The ZebraScope™ was modified with a protective device on its flexible tip, so that the plaque could be dissected from the wall of parent carotid artery and ablated completely without damage to the carotid artery. The holmium:YAG (Ho:YAG) and thulium fiber laser (TFL) generators were alternately used when needed.

Results

All the carotid atherosclerotic plaques were completely ablated by Ho:YAG laser and/or TFL. The Ho:YAG laser was more effective for the atherosclerotic plaques with severe calcification, while the TFL was more suitable for those with moderate calcification. There were still some thermal injury spots on the inner wall of the parent carotid artery caused by the laser in the non-protected group B. In the protected group A, on the contrary, there was no even a thermal injury spot was found on the relevant location except for one sample. The difference of ablating duration was statistically significant between group A (36.5 ± 4.79 min) and group B (63.4 ± 6.55 min) (P < 0.01).

Conclusion

According to our knowledge, this is the first attempt to ablate carotid atherosclerotic plaques assisted by the ZebraScope™ in vitro. The protective and dissecting device on the tip of the angioscope makes it safe and visible when the ablation is performed to carotid atherosclerotic plaques. The Ho:YAG laser and TFL are effective and safe for ablating the plaque in vitro.

Comprehensive Review of Physician Modified Aortic Stent Grafts: Technical and Clinical Outcomes

OBJECTIVE

Physician modified stent grafts (PMSGs) present satisfactory results in selected cases of complex aortic pathologies. However, the technique lacks standardisation and depends on the surgeon and aortic segment. The aim of this article is to review comprehensively the technical details and clinical results of PMSGs related to patients with pathology in all aortic locations.

METHODS

A MEDLINE search (last search 20 April 2020) identified 20 relevant papers in the English language published over the last 20 years evaluating clinical outcomes after a PMSG and specifying the technical details to design it.

RESULTS

Seven hundred and eleven patients were included in the analyses, with 59% being operated on as an emergency. Ninety-two per cent of abdominal aortic segment PMSGs (A-PMSGs) were performed either as an emergency or before 2012. The main indications were available in 670 cases; 435 were degenerative aneurysms (64.9%) and 171 were aortic dissections (25.5%). Most of the endografts used were composed of polyethylene terephthalate, except for the Ankura (expanded polytetrafluoroethylene [Lifetech Scientific, Shenzhen, China]; n = 50, 7.5%). The Valiant (Medtronic, Minneapolis, MN, USA) represented 65% (n = 169) of aortic arch PMSGs (aa-PMSGs) and the Zenith platform (Cook Medical, Bloomington, IN, USA) 51% (n = 139) of A-PMSGs. A snare was used to reinforce the fenestration in 458 PMSGs (66%) and a cautery device cut the fenestration in 484 (75%) PMSGs. No bridging stent was used in 47 (7.0%) PMSGs (these aa-PMSGs had large fenestrations). Technical success ranged from 87.5% to 100% and 30 day mortality from 0% to 8%. Primary branch patency ranged from 96.3% to 100% at 12 month follow up. Zero to 14% of patients experienced type 3 or type 1 endoleak at 14.8 month follow up.

CONCLUSION

PMSG is a useful technique, particularly when validated treatments are not available. However, it is a non-standardised technique and the long term consequences of modifications remain unknown.

Endarterectomy for Isolated Atherosclerotic Lesions of the Popliteal Artery

BACKGROUND

In the endovascular era, angioplasty has grown a large place in the treatment of peripheral artery disease. Few studies have been focused in short atherosclerotic lesions of the popliteal artery itself, which remain for many surgeons a critical zone for the technical approach decision. We herein describe simple techniques of popliteal endarterectomy for the treatment of short popliteal occlusive disease.

METHODS

Between January 2011 and June 2019, patients with isolated popliteal artery atherosclerotic lesions were included in this retrospective study. Indication for intervention was either disabling lower limb claudication or critical limb ischemia. We performed either endarterectomy by eversion of the popliteal artery or a simple endarterectomy with a patch angioplasty. We then studied the procedural data, the thirty-day outcomes, and the mid-term follow-up.

RESULTS

A total of 17 patients were included in the study, and 18 limbs were revascularized with the endarterectomy technique. Total duration of the procedure was 100 ± 46 min. Overall technical success was 100%. Median hospital stay was 4 days. Complete clinical success, that is, freedom from claudication or rest pain, was achieved in all cases. No early additional procedure was needed. After a mean follow-up of 34 ± 32 months with no patient lost to follow-up, all patients were alive, and a 100% primary patency and limb salvage was observed.

CONCLUSIONS

At 3 years' follow-up, endarterectomy of the popliteal artery appears to be a valid option for isolated and short atherosclerotic lesions.

Laser angioplasty of peripheral arteries: basic principles, current clinical studies, and future directions

Percutaneous transluminal angioplasty (PTA) is a routine procedure for the treatment of peripheral arterial disease. However, its main limitation is late restenosis occurring at a 1-year rate of 6%-60%. Restenosis arises from injury to the arterial wall including overstretching, compression and rupture of the atherosclerotic plaque during balloon inflation. It is hypothesized that better long-term angioplasty results are observed if atherosclerotic plaques are removed rather than compressed and fractured. Laser angioplasty is one method to remove atherosclerotic plaques. We discuss the principles of lasers, physical properties of laser light, history of laser angioplasty and effects of laser radiation on tissues. Large clinical studies using laser angioplasty are critically assessed. In comparison to conventional PTA, there are some advantages of laser angioplasty: easier passage through chronic and calcified occlusions and according to some studies, better short- and medium-term results regarding limb salvage and management of in-stent restenoses.