Design Optimization of Printed Multi-Layered Electroactive Actuators Used for Steerable Guidewire in Micro-Invasive Surgery

To treat cardiovascular diseases (i.e., a major cause of mortality after cancers), endovascular-technique-based guidewire has been employed for intra-arterial navigation. To date, most commercially available guidewires (e.g., Terumo, Abbott, Cordis, etc.) are non-steerable, which is poorly suited to the human arterial system with numerous bifurcations and angulations. To reach a target artery, surgeons frequently opt for several tools (guidewires with different size integrated into angulated catheters) that might provoke arterial complications such as perforation or dissection. Steerable guidewires would, therefore, be of high interest to reduce surgical morbidity and mortality for patients as well as to simplify procedure for surgeons, thereby saving time and health costs. Regarding these reasons, our research involves the development of a smart steerable guidewire using electroactive polymer (EAP) capable of bending when subjected to an input voltage. The actuation performance of the developed device is assessed through the curvature behavior (i.e., the displacement and the angle of the bending) of a cantilever beam structure, consisting of single- or multi-stack EAP printed on a substrate. Compared to the single-stack architecture, the multi-stack gives rise to a significant increase in curvature, even when subjected to a moderate control voltage. As suggested by the design framework, the intrinsic physical properties (dielectric, electrical, and mechanical) of the EAP layer, together with the nature and thickness of all materials (EAP and substrate), do have strong effect on the bending response of the device. The analyses propose a comprehensive guideline to optimize the actuator performance based on an adequate selection of the relevant materials and geometric parameters. An analytical model together with a finite element model (FEM) are investigated to validate the experimental tests. Finally, the design guideline leads to an innovative structure (composed of a 10-stack active layer screen-printed on a thin substrate) capable of generating a large range of bending angle (up to 190°) under an acceptable input level of 550 V, which perfectly matches the standard of medical tools used for cardiovascular surgery.

Thoracic outlet syndrome: single-center experience on the transaxillary approach with the aid of the TRIMANO Arthrex arm

Thoracic outlet syndrome (TOS) is a pathology caused by compression on the neurovascular bundle by the first rib. The treatment of TOS is conservative management by analgesia and physiotherapy; however, if there is no response to conservative treatment, surgery is indicated through thoracic outlet decompression by first rib resection. Several surgical techniques are available, including supraclavicular, transaxillary, and transthoracic first rib resection approaches. The transaxillary approach provides better visualization on the neurovascular bundle and, thus, is sometimes the preferred method of treatment. The transaxillary approach has been criticized due to safety concerns regarding the neural bundle during surgical exposure. During surgery, hyperabduction of the arm is obtained by a surgical assistant, and the quality of exposure can decrease with time, or an iatrogenic injury to the neural bundle (brachial plexus) can occur from the hyperabduction. The use of the TRIMANO Arthrex arm can help in the exposure, instead of a surgical aide, because it provides stable exposure and visualization for the operating surgeon. We performed a retrospective review of patients undergoing transaxillary first rib resection using the TRIMANO Arthrex arm between June 2021 and December 2022. During installation, the patient is placed in the lateral decubitus position and the TRIMANO Arthrex arm is fixed at the operating table at the height of the patient's shoulder. Thus, the surgical aide can help the surgeon during the surgery, rather than placing the arm into and out of hyperabduction. The use of hyperabduction is limited to 15 minutes, followed by 5 minutes of rest, to decrease the tension on the neurovascular bundle. The surgeon then performs the transaxillary approach and systematically resects the first rib, scalene muscles, and subclavian muscles. By this approach, the inferior brachial plexus is also lysed. In our review, we found a total of 15 procedures of first rib resection for the treatment of TOS with the aid of the TRIMANO Arthrex arm that met our inclusion criteria. All procedures were performed by the same surgeon. None of the patients sustained an injury to the neurovascular bundle. All the patients had an uneventful hospital stay postoperatively, and none presented with a hematoma. The drain placed during surgery was removed on postoperative day 2. All patients had at least one radiograph taken during their hospitalization, with no pleural effusion or pneumothorax found. The use of the TRIMANO Arthrex arm is safe and can help in the positioning and installation of the patients undergoing transaxillary first rib resection. It decreases the number of surgical assistants and offers great comfort for the surgeon because it provides stable exposure for the operating surgeon.

Common Femoral Artery Curvature During Hip Flexion

PURPOSE

To assess the conformational changes of the common femoral artery (CFA) during hip joint flexion in patients without atherosclerosis.

METHODS

Patients who underwent digital subtraction angiography for suspicion of arterial endofibrosis between 2007 and 2011 were retrospectively searched. Angiographic images were analyzed by two independent readers. The CFA was divided into four segments of equal length, and the segment containing the folding point was noted. Segments 1 and 2 were located in the proximal half of the CFA and segments 3 and 4 in the distal half. Readers assessed the CFA angulation, located the arterial folding point, and classified the CFA curvature as harmonious, or as a moderate or severe plication.

RESULTS

Forty patients were included. The Lin concordance correlation coefficients, used to evaluate inter-observer variability, were 0.90 (95% CI [0.83; 0.96]), 0.96 (95% CI [0.93; 0.98]) and 0.96 (95% CI [0.94; 0.98]) for the measures of the CFA angle during flexion, of the length between the superficial circumflex iliac artery and the folding point, and of the length between the folding point and the femoral bifurcation, respectively. The CFA curvature was described as harmonious in 12 patients, moderate plication in 14 patients, and severe plication in 14 patients. The CFA folding point was located on segment 1, 2 and 3 in 6, 26 and 8 patients, respectively; no folding point was located on segment 4.

CONCLUSION

In these patients with non-atheromatous disease, hip flexion yielded most frequently a harmonious curvature or a moderate plication of the CFA.

American Society of Anesthesiologists-Physical Status Classification As An Independent Risk Factor of Surgical Site Infection After Infra-Inguinal Arterial Bypass

OBJECTIVES

The present study aimed to assess whether high-risk American Society of Anesthesiologists (ASA)-Physical Status was an independent risk factor for the development of surgical site infection (SSI) after infra-inguinal lower extremity bypass (LEB).

SUMMARY OF BACKGROUND DATA

The ASA-Physical Status Classification System assesses the overall physical status preoperatively. ASA-Physical Status is associated with postoperative morbidity and mortality. However, limited data are available on how ASA-Physical Status Class affects the development of SSI after infra-inguinal LEB.

METHODS

Patients who had undergone infra-inguinal LEB from January 1, 2015 to December 31, 2018, for obliterative arteriopathy or popliteal aneurysm at our university hospital were included. SSI risk factors were identified using multivariable logistic regression. The length of hospital stay, major limb events (MALE), major adverse cardiovascular events (MACE), and all-cause mortality were compared for patients with SSI versus those without SSI 3 months and 1- year of follow-up after the index surgery.

RESULTS

Among the 267 patients included, 30 (11.2%) developed SSI during the 3-month period and 32 (12%) at 1 year. ASA-Physical Status ≥3 [odds ratio (OR): 3.7, 95% confidence interval CI) 1.5-11.1], emergency surgery (OR: 2.7, 95% CI 1.2-6.0), general anesthesia (OR: 2.8, 95% CI 1.3-6.1), and procedure performed by a junior surgeon (OR: 2.7, 95% CI 1.3-6.0) were independently associated with SSI. At 3 months and 1 year, SSI was significantly associated with MALE (including surgical wound debridement, subsequent thrombectomy, major amputation), length of hospital stay, and all-cause mortality.

CONCLUSION

The ASA-Physical Status should be considered in medical management when an infra-inguinal LEB is considered in frail patients, to prevent surgical complications.

Percutaneous Axillary Artery Puncture: An Efficient Approach for Upper Extremity Access

BACKGROUND

The aim was to analyze the anatomic feasibility of the percutaneous axillary access (PAXA) using cadaverous models and then to analyze the complications associated with PAXA during Fenestrated or Branched Endovascular Aneurysm Repair (F/BEVAR) procedures.

METHODS

Cadaverous models were used to analyze axillary pedicle after a PAXA on an initial anatomical investigation. A subclavian approach was performed after puncture to assess the injuries caused by the needle. Then, in an observational study, patients who underwent F/BEVAR using a PAXA between July 2019 and July 2021 were included. PAXA-related events and complications were monitored.

RESULTS

Eleven dissections were performed on cadavers. The axillary vein was injured twice (18.2%); the puncture site on the axillary artery was found on the arterial proximal part, behind the clavicle. Fifty-three patients underwent a F/BEVAR using a PAXA. The mean (SD) age of patients was 74.5 (9.7) years. Most indications for endovascular repair were para-renal aneurysms (66%). Two Proglide® closure devices served to close arterial access in all procedures. Adjunct balloon inflation was used in 19 (35.8%) patients. There were 5 (9.4%) PAXA-related events included preoperative blush in 2 (3.8%) patients, axillary artery dissection in 2 (3.8%), and 1 (1.9%) axillary artery stenosis. Five patients (9.4%) had a postoperative axillary hematoma without need for additional surgical procedure. No PAXA-related complication was found after discharge (mean [SD] 11.7 [7.4] months following surgery).

CONCLUSIONS

Percutaneous axillary artery access was an efficient upper extremity access and associated with a low rate of PAXA-related events.

EndoSuture aneurysm repair versus fenestrated aneurysm repair in patients with short neck abdominal aortic aneurysm

OBJECTIVE

The aim of this study was to compare midterm results of EndoAnchors in EndoSuture aneurysm repair (ESAR) versus fenestrated endovascular aneurysm repair (FEVAR) in short neck abdominal aortic aneurysm (AAA).

METHODS

All patients who underwent an ESAR procedure for a short neck AAA at our center between September 2017 and May 2020 were considered for analysis. To form the control group, preoperative computed tomography angiography of patients who underwent FEVAR for juxtarenal AAA between April 2012 and May 2020 were reviewed and patients who met short neck criteria selected. A propensity-matched score on neck length and neck diameter was calculated, resulting in 18 matched pairs. AAA shrinkage, type Ia endoleaks (EL), AAA-related reinterventions, and AAA-related deaths were compared.

RESULTS

The median AAA diameter was 54 mm (interquartile range [IQR], 52-61 mm) versus 58 mm (IQR, 53-63 mm) with a median neck length of 8 mm (IQR, 6-12 mm) vs 10 mm (IQR, 6-13 mm) in ESAR and FEVAR patients, respectively. Technical success was 100% in both groups. Procedural success was 94% in the ESAR group versus 100% in the FEVAR group. The median procedure duration was 138 mm (IQR, 113-182 mm) vs 240 mm (IQR, 199-293 mm) ( P < .001) and the median length of stay was 2 days (IQR, 2-3 days) vs 7 days (IQR, 6-7 days) (P < .001) in ESAR and FEVAR patients, respectively. No major hospital complications were observed in ESAR patients compared with two in FEVAR patients (11%) with one transient acute kidney injury and one transient paraplegia. The median follow-up was 23 months (IQR, 19-33 months) vs 36 months (IQR, 22-57 months) with 67% versus 61% AAA shrinkage in the ESAR and FEVAR groups, respectively (P = .73). No type Ia EL, proximal neck-related reinterventions, or AAA-related deaths were observed in either group. No AAA-related reintervention was observed in the ESAR group versus three reinterventions in the FEVAR group (P = .23).

CONCLUSIONS

ESAR seems to be a safe technique with no major postoperative complications or reinterventions observed during follow-up. It seems to offer similar midterm results as FEVAR in terms of type Ia EL, aneurysm shrinkage, and aneurysm-related mortality. ESAR seems to be a good off-the-shelf alternative to FEVAR in case of technical constraints.

Femoral artery ligature for treatment of infected groin pseudoaneurysm in injected drug abusers

Drug addiction is a major social and medical concern. Infected groin pseudoaneurysm (IGP) is the result of direct arterial needlestick injury associated with contamination of the arterial wall or peri-arterial area by the injection equipment. Femoral artery (FA) ligation with extensive debridement is an alternative to direct revascularization in an area of sepsis. In case of femoral bifurcation free of infection or in case of isolated FA below the femoral artery of thigh involvement, a simple ligation of the FA is performed. Ligation of each femoral vessel is indicated in case of extension of the infection to the femoral bifurcation. Proximal ligation is performed on the proximal part of the FA. Distal ligation is performed on the proximal part of the deep artery of thigh and the FA below the origin of the deep artery of thigh. Ligation is effective and represents an appropriate method to control hemorrhage and sepsis syndrome in IGP.

Effectiveness of an individualized home-based physical activity program in surgery-free non-endarterectomized asymptomatic stroke patients: a study protocol for the PACAPh interventional randomized trial

Background

Carotid atherosclerotic plaques remain silent until their rupture, which may lead to detrimental ischemic events such as strokes. This is due, in part, to intraplaque hemorrhages (IPH) and the resulting inflammatory processes, which may promote carotid plaque vulnerability. Currently, the benefits of carotid endarterectomy remain unclear for asymptomatic patients. Interestingly, the completion of physical activity (PA) may have beneficial effects; however, the paucity of current data warrants robust longitudinal interventions. We therefore aim to study the effects of a 6-month longitudinal personalized home-based PA program on IPH, biological, and inflammatory markers in asymptomatic stroke patients.

Methods

Eighty patients (≥ 18 years old) will be recruited for the Physical Activity and Carotid Atherosclerotic Plaque Hemorrhage (PACAPh) clinical trial from the Hospices Civils de Lyon. Patients will be eligible if they present with carotid stenosis ≥ 50% and are asymptomatic from any ischemic events for at least 6 months. Recruited patients will be randomized into either a PA or a control group, and assessed at baseline and after 6 months. At both time points, all patients will be assessed using magnetic resonance imaging to assess IPH, blood sampling to measure inflammatory markers and monocytic phenotyping, PA and sedentary behavior questionnaires, 6-min walking test, and maximal isometric quadricep contraction test. The randomized PA intervention will consist of reaching a daily walking step goal individually tailored to each patient. Steps will be collected using a wirelessly connected wristband. The number of steps completed by individuals in the PA group will be re-evaluated bimonthly to encourage walking habits.

Discussion

The PACAPh study is the first of its kind representing a feasible, easily accessible therapeutic strategy for asymptomatic stroke patients. We hypothesize that the personalized home-based PA program will reduce IPH and modulate inflammatory and biological parameters in patients presenting with carotid plaques. If the results of the PACAPh study prove to be beneficial on such health parameters, the implementation of such kind of intervention in the daily treatment of these patients would be an advantageous and cost-effective practice to adopt globally.

Trial registration

This study has been approved by the National Ethics Committee (IDRCB:2019-A01543-54/SI:19.06.21.40640). ClinicalTrials.gov NCT04053166

Natural History of Asymptomatic Superior Mesenteric Arterial Stenosis Depends on Coeliac and Inferior Mesenteric Artery Status

OBJECTIVE

The benefit of preventive treatment for superior mesenteric artery (SMA) stenosis remains uncertain. The latest European Society for Vascular Surgery (ESVS) guidelines remain unclear given the lack of data in the literature. The aim of this study was to evaluate asymptomatic SMA stenosis prognosis according to the presence of associated coeliac artery (CA) and/or inferior mesenteric artery (IMA) stenosis.

METHODS

This was a single academic centre retrospective study. The entire computed tomography (CT) database of a single tertiary hospital was reviewed from 2009 to 2016. Two groups were defined: patients with isolated > 70% SMA stenosis (group A) and patients with both SMA and CA and/or IMA > 70% stenosis (group B). Patient medical histories were reviewed to determine the occurrence of mesenteric disease (MD) defined as development of acute mesenteric ischaemia (AMI) or chronic mesenteric ischaemia (CMI).

RESULTS

Seventy-seven patients were included. Median follow up was 39 months. There were 24 patients in group A and 53 patients in group B. In group B, eight (10.4%) patients developed MD with a median onset of 50 months. AMI occurred in five patients with a median of 33 months and CMI in three patients with a median of 88 months. Patients of group B developed more MD (0% vs. 15.1%; p = .052). The five year survival rate was 45% without significant difference between groups.

CONCLUSION

Patients with SMA stenosis associated with CA and/or IMA seem to have a higher risk of developing mesenteric ischaemia than patients with isolated SMA stenosis. Considering the low life expectancy of these patients, cardiovascular risk factor assessment and optimisation of medical treatment is essential. Preventive endovascular revascularisation could be discussed for patients with non-isolated > 70% SMA stenosis, taking into account life expectancy.

Analysis of Preoperative CT Scan Can Help Predict Technical Failure of Endovascular Treatment of TASC C-D Aortoiliac Chronic Total Occlusions

BACKGROUND AND AIMS

To evaluate if features of occlusion analyzable on preoperative computed tomography scan could predict risks of technical failure or iliac rupture of endovascular treatment of TransAtlantic InterSociety Consensus C-D aortoiliac chronic total occlusion.

METHODS AND RESULTS

All patients treated by endovascular techniques for a TransAtlantic InterSociety Consensus C-D aortoiliac chronic total occlusion between 2009 and 2016 were included (107 patients, 148 iliac arteries). We evaluated the location of the occlusion and the importance of the arterial calcifications. For this factor, patients were divided into 3 groups: the Black occlusion group with mild or no calcifications, the white occlusion group with moderate no protrusive calcifications, and the white protrusive occlusion group with heavy endoluminal calcifications. Technical failure occurred in 11 iliac arteries and peroperative iliac rupture in 6. The location in the external iliac artery is the most significate risk factor of technical failure in univariate (OR = 9.93; P = 0.0012) and multivariate analysis (OR = 15.26; P = 0.0006). The presence of heavy endoluminal calcifications is a further significate risk factor (OR = 13.88; P = 0.0365). Rupture rate was comparable between the 3 groups.

CONCLUSIONS

Preoperative computed tomography scan can predict risk of technical failure but not of iliac rupture.

Intra-arterial thrombolysis in acute popliteal artery occlusion is a safe and effective technique reducing the rate of open surgery

BACKGROUND

Acute popliteal artery occlusion is a frequent clinical entity with a risk of major amputation. Several attitudes are possible and treatment is not standardized. The purpose of this study is to demonstrate safety and effectiveness of intra-arterial thrombolysis in acute popliteal artery occlusion.

METHODS

This is a retrospective analysis of a prospective database of patients treated by intra-arterial thrombolysis for acute lower-limb ischemia due to popliteal artery occlusion between 2001 and 2014.The primary endpoint was technical and clinical success. Etiologies and etiologic treatment, amputation-free survival, in-hospital mortality and bleeding complications rates were secondary endpoints.

RESULTS

Seventy-one patients, with a mean 6-day-old ischemic time before thrombolysis, were analyzed. Technical and clinical success was 90% and 87% respectively. Etiology was embolic in 33 patients (cardiac N.=14, aortic=6, unknown=13) and thrombotic in 38 (atheromatous N.=19, entrapment N.= 4, popliteal aneurysm N.=11, Buerger N.=2, thrombophilia N.=1, hyperhomocysteinemia N.=1). Survival and amputation-free survival at 30 days were 97% and 94% respectively. There were no major bleeding complications.

CONCLUSIONS

Intra-arterial thrombolysis of acute popliteal artery occlusion is an effective technique which reduces the rate of open surgery. The risk of bleeding complications is very low.

Minithoracotomy and Beating Heart Strategy for Mitral Surgery in Secondary Mitral Regurgitation

BACKGROUND

In patients with secondary mitral regurgitation (MR) associated with low ejection fraction or previous heart surgery, minimally invasive mitral valve surgery without aortic cross-clamp (MIMVS-WAC) has shown promising results. We report our experience for this strategy in our centers.

METHODS

Between August 2011 and April 2017, 46 patients (mean age 69 ± 11 years, 76% males) received MIMVS-WAC. Indications for this technique were prior coronary bypass surgery (26%), severe or recent left ventricular (LV) dysfunction (30%), or both (39%). The mean EuroSCORE II was 12 ± 10.

RESULTS

For each procedure, we conducted right minithoracotomy and hypothermic cardiopulmonary bypass (CPB) after peripheral cannulation. Mean CPB time was 159 ± 39 minutes. A mitral valve replacement (MVR) was performed in 23 cases (50%), an annuloplasty in 22 cases (48%), and a prosthesis pannus removal in 1 case (2%). Mean hospital length of stay was 12 ± 5.4 days. We report no sternotomy conversions, six reoperations for bleeding, and three deaths at 30 days. Transfusion was requested in 62% (mean infusion 2 ± 2.4 packed red blood cells). The postoperative echocardiography showed an LV function preservation in 69% of cases and a reduction of pulmonary arterial pressure in 73% of cases. Four additional deaths occurred in the long-term follow-up (mean 637 ± 381 days, median 593 days). No mitral reoperation was required, with a MR ≤ 2 in 90% of patients.

CONCLUSION

In high-risk patients, the MIMVS-WAC is a safe technique. It avoids hard dissections while ensuring excellent preservation of cardiac function.

A Thrombosed Popliteal Aneurysm Ruptured in the Setting of Chronic Limb Ischemia: A Rare Complication that Can Occur at Long Term

Rupture of a chronic thrombosed or excluded popliteal arterial aneurysm is rare, but has been previously reported in the literature. The management of a ruptured thrombosed popliteal aneurysm, in a context of chronic limb ischemia, raises the problem of latent ischemia and its outcome. In this case report, we present the first case of a ruptured thrombosed popliteal aneurysm in a patient presenting chronic ischemia.