Comparing the Efficacy of Endovascular Simulation Training in Different Training Formats: A Randomized Controlled Trial.

BACKGROUND: High-fidelity endovascular simulators have demonstrated significant potential in enhancing interventionalists' performance metrics, including procedure time (PT), fluoroscopy time (FT), and contrast volume (CV) usage. However, it is less clear whether trainee performance, when assessed using both multidimensional global and procedure-specific rating scales (PSRS), improves in a manner consistent with these metric parameters. This study aimed to determine whether the structure of the training-conducted in block sessions or weekly intervals-impacts the effectiveness of the training. METHODS: Twenty students were enrolled in this prospective, randomized, controlled, single-center trial. They were randomly divided into block and weekly training groups, each undergoing 6 hrs of supervised endovascular training on a Mentice simulator over a span of 3 weeks. At the outset and conclusion of their training, students performed a predefined peripheral endovascular intervention, which was assessed by an experienced interventionalist. Furthermore, participants were prompted to complete a survey at both the beginning and the end of the study. RESULTS: Both groups exhibited significant improvements in PT, FT, CV usage, global rating scale (GRS) scores, and performance-specific rating scale scores. However, no significant difference was observed between the 2 groups. The simulator training notably boosted the trainee's self-confidence. CONCLUSIONS: Simulator training not only enhances metric performance parameters but also improves performance as assessed by both GRS and PSRS. Whether the training is conducted in block sessions or weekly intervals did not affect its efficacy. As such, the training format can be tailored to best fit the specific circumstances and setting.

The Mangled Extremity Severity Score (MESS) does not predict amputation in popliteal artery injury.

PURPOSE: Vascular injuries in lower extremity trauma, especially with involvement of the popliteal artery, are associated with considerably high rates of limb loss, especially with blunt trauma mechanisms. The aim of this study was to evaluate the risk of amputation in patients with traumatic popliteal artery lesions with special focus on the validity of the Mangled Extremity Severity Score (MESS). METHODS: In this retrospective study, all patients treated for isolated lesions of the popliteal artery following trauma between January 1990 and December 2020 at a high-volume level I trauma center were included. Primary outcome was limb salvage dependent on MESS and the influence of defined parameters on limb salvage was defined as secondary outcome. The extent of trauma was assessed by the MESS. RESULTS: A total of 50 patients (age 39.2 ± 18.6 years, 76% male) with most blunt injuries (n = 47, 94%) were included. None of the patients died within 30 days and revascularization was attempted in all patients with no primary amputation and the overall limb salvage rate was 88% (44 patients). A MESS ≥ 7 was observed in 28 patients (56%) with significantly higher rates of performed fasciotomies (92.9% vs. 59.1%; p < 0.01) in those patients. MESS did not predict delayed amputation within our patient cohort (MESS 8.4 ± 4.1 in the amputation group vs. 8.1 ± 3.8 in the limb salvage group; p = 0.765). CONCLUSION: Revascularization of limbs with isolated popliteal artery injuries should always be attempted. MESS did not predict delayed amputation in our cohort with fasciotomy being an important measure to increase limb salvage rates.

Long-Term Results of Endovascular Treatment with Nitinol Stents for Femoropopliteal TASC II C and D Lesions.

Background and Objectives: The feasibility of endovascular treatment (EVT) for Trans-Atlantic Inter-Society Consensus (TASC) II C and D femoropopliteal artery lesions has been described, but no prospective study has performed a long-term follow-up. The aim of this study was to report the long-term results of nitinol stents (NS) for the treatment of long femoropopliteal lesions. Materials and Methods: A single-center prospective, randomized controlled trial (RCT) comparing EVT with NS and vein bypass surgery was previously performed. The EVT group's follow-up was extended and separately analyzed with primary patency as the primary endpoint. The secondary endpoints were technical success, secondary patency, reinterventions, limb salvage, survival, complications, and clinical improvement. Results: Between 2016 and 2020, 109 limbs in 103 patients were included. A total of 48 TASC II C and 61 TASC II D lesions with a mean lesion length of 264 mm were reported. In 53% of limbs, the indication for treatment was chronic limb-threatening ischemia. The median follow-up was 45 months. Technical success was achieved in 88% of cases, despite 23% of the lesions being longer than 30 cm (retrograde popliteal access in 22%). At four-year follow-up, primary patency, secondary patency, and freedom from target lesion revascularizations were 35%, 48%, and 58%, respectively. Limb salvage and survival were 90% and 80% at 4 years. Clinical improvement of at least one Rutherford category at the end of follow-up was achieved in 83% of limbs. Conclusions: This study reports the longest follow-up of endovascular treatment with nitinol stents in femoropopliteal TASC II C and D lesions. The results emphasize the feasibility of an endovascular-first strategy, even in lesions beyond 30 cm in length, and clarify its acceptable long-term durability and good clinical outcomes. Large multicenter RCTs with mid- and long-term follow-up are needed to investigate the role of different endovascular techniques in long femoropopliteal lesions.

[Establishment of a new research concept at a university location]. / Die Etablierung eines neuen Forschungskonzepts an einem universitären Standort.

Apart from daily clinical work and patient care, research and student teaching are essential assignments of a university hospital. The implementation of a completely new research laboratory at the Department of Vascular Surgery at the Medical University of Innsbruck led to the creation of a novel infrastructure for the design and set-up of a newly founded research focus. The cooperation with national as well as international research collaborators was essential for this process. The construction of a research network is not only important for the design and conception of a new research laboratory but also for the development of new study protocols and exchange and discussion of results. After the successful implementation of Experimental Vascular Surgery in Innsbruck, the realization of basic research projects as well as translational research projects is possible at this university location. Moreover, simulation training is an emerging field of research that aims to add more realistic surgical skills to residency programs, attract future residents and teach more complex novel techniques.

Risk factors for major amputation after arterial vascular trauma of the lower extremity.

BACKGROUND & OBJECTIVE: Arterial vascular trauma bears a great risk of poor functional outcome or limb loss. The aim of this study was to analyze amputation rates of patients after vascular trauma and to perform a predictor analysis for the risk of major amputation. METHODS: In a single-center retrospective analysis of 119 extremities treated for arterial vascular injury between 1990 and 2018 amputation rates and factors associated with limb loss were assessed. All patients were treated for traumatic vascular injuries; iatrogenic injuries were not included in the study. RESULTS: During the study period, a total of 119 legs in 118 patients were treated after arterial vascular trauma. The in-hospital major amputation rate was 16.8% and the mortality rate was 2.5%. In the predictors analysis, vascular re-operation (amputation rate 53.8% vs 12%, odds ratio = 8.56), a Rutherford category ⩾IIb (25.4% vs 4.2%, odds ratio = 6.43), work-related or traffic accidents (28.2% vs 0%, odds ratio = 4.86), concomitant soft tissue or bone injuries (26.7% vs 7.3%, odds ratio = 4.64), polytrauma (33.3% vs 12%, odds ratio = 3.68), and blunt trauma (18.9% vs 0% for penetrating trauma, odds ratio = 1.64) were found to be associated with amputation. CONCLUSIONS: Lower extremity arterial vascular trauma was associated with a significant major amputation rate. Several predictors for limb loss were identified, which could aid in identifying patients at risk and adapting their treatment.

Comparison of Prosthetic and Vein Bypass with Nitinol Stents in Long Femoropopliteal Lesions.

BACKGROUND: Guidelines for the treatment of long femoropopliteal lesions are not based on a high level of evidence and recent randomized controlled trials (RCTs) challenge vein bypass (VBP) as the recommended therapy. This study compared prosthetic (PTFE) bypass, VBP and angioplasty with nitinol stents in long femoropopliteal lesions. METHODS: Pooled data from a RCT and a retrospective database with the same inclusion criteria were analyzed with primary and secondary patency as well as freedom from target lesion revascularization (TLR) as primary endpoints. RESULTS: Between 2016 and 2018 a total of 172 lesions were treated in three groups (PTFE: n = 62, VBP: n = 55, stent: n = 55). Clinical and lesion characteristics were similar with mean lesion lengths between 260 and 279mm. Technical success rate in the stent group was 87%. There were no significant differences between the groups in patency rates, freedom from TLR, limb salvage and survival during 2-year follow-up. The primary patency rates for the PTFE, VBP and stent groups were 50%, 56% and 60% at 2 years. The PTFE group had significantly less complications compared to the other groups and a shorter hospital-stay compared to the VBP group. Clinical improvement was significantly better in the PTFE and VBP group compared to the stent group. CONCLUSIONS: The 2-year results indicate that the role of VBP as the recommended therapy for long femoropopliteal lesions may not be unchallenged due to the similar results in all three groups. Further RCTs are needed to determine the best revascularization modality for long femoropopliteal lesions.

Ultrasound-Guided Fibrin Glue Injection for Treatment of Iatrogenic Femoral Pseudoaneurysms.

INTRODUCTION: Arterial pseudoaneurysms (PSAs) are the most common access site complication following transarterial catheter intervention. Ultrasound-guided injection of thrombogenic substances into perfused arterial PSAs followed by compression therapy is a well-established and less invasive treatment option than surgical repair. Different agents are available to induce thrombosis including thrombin and a fibrin-based tissue glue, which is used as first-line treatment at our institution. This paper deals with our experience using ultrasound-guided fibrin glue injection (UGFI). MATERIALS AND METHODS: Retrospective data analysis: all patients (55) treated for iatrogenic femoral PSA following digital subtraction angiography of the lower extremities between January 1, 2010, and December 31, 2018, were included. Data on epidemiology, PSA location and size, vascular risk factors, fibrin glue injection (fibrin glue volume), primary success rate of UFGI, and complications related to the treatment were analyzed. RESULTS: A total of 55 consecutive femoral iatrogenic PSAs were treated during the defined period and 32 (58.2%) of the patients were female. Imaging was performed using ultrasound in all cases. The most common PSA location (80.0%) was the common femoral artery, mean PSA size (± SD) was 2.7 ± 1.2 cm, and neck length was 1.6 ± 1.0 cm. The dose (mean ± SD) of fibrin glue was 2.6 mL (± 1.0; maximum: 6 mL). Primary UGFI success rate was 87.3% and conversion rate to open surgery was 12.7%. Two (4%) patients required embolectomy for peripheral embolization after UGFI. CONCLUSION: Early results achieved with UGFI for treatment of iatrogenic femoral PSA are promising. In our cohort, UGFI was a safe and effective first-line alternative to traditional open surgery, which then was unnecessary in the vast majority of PSA cases. Further prospective studies for comparison of ultrasound-guided techniques should be encouraged.

Regeneration of Mitochondrial Function in Gastrocnemius Muscle in Peripheral Arterial Disease After Successful Revascularisation.

OBJECTIVE: Myopathy, characterised by altered mitochondrial function, is a central part of the pathophysiology of peripheral arterial disease and the aim of this study was to investigate the effect of revascularisation on mitochondrial function. METHODS: High resolution respirometry was used to investigate mitochondrial respiration and the results were normalised to citrate synthase activity (CSA), a marker of mitochondrial content. Ten patients with symptomatic peripheral arterial disease (study group) and 10 subjects without ischaemia (control group) were included. Ankle brachial index and ultrasound imaging were performed before and after vascular intervention to confirm technically successful revascularisation. Within the study group, muscle biopsies from the gastrocnemius muscle were taken before vascular intervention and six weeks after revascularisation. Within the control group, tissue was harvested once. RESULTS: There were no significant group differences regarding anthropometric data. CSA showed a significant increase after successful revascularisation (CSA pre-operative 281.4 (252.4-391.8) nmol/min/mg protein vs. CSA post-operative 438.5 (361.4-471.3) nmol/min/mg protein; p = .01) with post-operative return of values to the range of control subjects (CSA control 396.6 (308.2-435.9)). Mitochondrial respiration normalised to CSA in oxidative phosphorylation (P) as well as in electron transfer (E) capacity were significantly reduced post-operatively when compared with pre-operative values (P pre-operative 0.218 (0.196-0.266) pmol/(sec×mg) per CSA vs. post-operative 0.132 (0.116-0.150) pmol/(sec×mg) per CSA, p = .007; E pre-operative 0.230 (0.195-0.279) pmol/(sec×mg) per CSA vs. post-operative 0.129 (0.120-0.154) pmol/(sec×mg) per CSA, p = .005) meaning a post-operative return of values to within the range of control subjects (P control 0.124 (0.080-0.155) pmol/(sec×mg) per CSA; E control 0.121 (0.079-0.125) pmol/(sec×mg) per CSA). CONCLUSION: With these results, it has been shown that the initially impaired mitochondrial function and content can normalise after revascularisation.

Femoral access site closure without prior femoral angiography : A retrospective analysis.

AIMS AND BACKGROUND: Although guideline recommendations have shifted towards a transradial route, femoral puncture is still an established vascular access, especially for complex coronary interventions. The FemoSeal™ vascular closure device (FVCD) helps to reduce femoral compression time and access site complications after removal of the catheter sheath. To ensure safe use, an angiography of the femoral artery prior to FVCD deployment is recommended by the manufacturer. We postulate that omitting this angiography does not relevantly increase the risk for vascular complications. METHODS AND RESULTS: In this retrospective analysis of an all-comers population (n = 1923) including patients receiving a percutaneous coronary intervention (PCI), we could show that combined vascular complication rates without femoral angiography were low (primary endpoint 4.6%) and comparable to a randomized clinical trial that did perform angiography of the vascular access site in a cohort of patients receiving diagnostic coronary angiography only. In addition to this analysis, we could demonstrate that patients with an acute coronary syndrome, receiving periprocedural anticoagulation or anti-platelet therapy had an increased risk for the formation of arterial pseudoaneurysms; however, we did not observe any ischemic vascular event after FVCD deployment. CONCLUSION: Closure of the femoral access site after coronary angiography using the FVCD can be safely performed without femoral angiography; however, due to an increased risk for the formation of pseudoaneurysms we recommend the transradial access in situations with increased bleeding risk.

Aortic Foreign Body Caused by Rupture of Endobag after EVAS Using the Nellix Aneurysm Sealing System-A Case Report.

The Nellix aneurysm sealing system aims at sealing the cavity of the sac of the aneurysm, to reduce typical complications such as migration or endoleak. We report on a case of a unique device-associated complication: rupture and displacement of the filling material into the aortic lumen, causing peripheral ischemia and imminent renal and visceral occlusion, in a patient with anastomotic ulcer after an open aortobiiliac bypass and calcified and tortuous iliac arteries. The material was removed by open surgery. The patient recovered completely. The device should be handled with great caution in cases with hostile access routes, and in secondary interventions.

Subclavian artery rupture in a young man during excessive weight lifting.

We report a 19-year-old man with rupture of the right subclavian artery after an excessive exercise of weight lifting. Imaging showed a hematothorax and hematomediastinum, a pseudoaneurysm with a maximum diameter of 4 cm, and a dissection of the right vertebral artery. As an emergency procedure an interposition graft was performed for reconstruction of the right subclavian artery. The patient's postoperative course was uneventful, and he was symptom free except for regressive hoarseness due to a paresis of the right recurrent laryngeal nerve.

Treatment options of crural pseudoaneurysms.

BACKGROUND: Pseudoaneurysms (PAs) of crural arteries represent rare complications of vascular interventions or surgery. Management of crural PAs includes different treatment options, conservative treatment as well as open surgery or endovascular procedures. We reviewed our experience. PATIENTS AND METHODS: We retrospectively analysed all patients who were diagnosed with crural PAs since 2003. We evaluated etiology, treatment and outcome. Endpoints were target vessel patency, vascular re-intervention and limb loss. RESULTS: A total of 30 patients were diagnosed with crural PAs. PA was caused by vascular intervention in 27 patients (90 %): open balloon thrombectomy (n = 25), subfascial endoscopic perforator vein surgery (n = 1) and transcutaneous catheter-assisted thrombus aspiration (n = 1). In 3 patients (10 %) it was caused by orthopaedic surgical procedures. Location of crural PAs were peroneal artery (n = 11; 36.7 %), posterior tibial artery (n = 10; 33.3 %), anterior tibial artery (n = 5; 16.7 %), and tibioperoneal trunk (n = 4; 13.3 %). Treatment of crural PAs included open surgery (n = 3; 10 %), endovascular procedures (n = 13; 43.3 %) such as endograft implantation (n = 9) or coil embolisation (n = 4), and conservative management (n = 14; 46.7 %). After a median follow-up period of 7 months (range: 0 - 46 months) 8 of 9 endografts were occluded, in none of these patients a minor or a major amputation was necessary. None of the surgically, endovascularly and conservatively treated patients needed a re-intervention for crural PA. A major amputation was necessary in 4 patients due to progression of peripheral arterial disease; none was a directly consequence of the crural PA. CONCLUSIONS: Crural PAs are mainly caused by vascular intervention, most frequently by catheter thrombectomy. As a consequence, we recommend fluoroscopic-assisted balloon thrombectomy over a guide wire as routine technique. In many cases of crural PAs, conservative management is sufficient. The choice of treatment of crural PAs depends on size, location and associated symptoms. Endovascular treatment using endografts is limited by poor long-term patency.