Fundamental Technical Skills of Endovascular Surgery: A Preliminary Study on Its Impact on Skills and Stress during Procedures.

BACKGROUND: Our objective is twofold: determining if simulation allows residents to reach proficient surgeons' performance concerning fundamental technical skills of endovascular surgery (FEVS) while investigating effects of the program on surgeons' stress. METHODS: Using a FEVS training simulator, 8 endovascular FEVS were performed by vascular surgery residents (simulator-naive or simulator-experienced residents [SER]) and seniors. Total time needed to complete the 8 tasks, called total completion time (TCT), was the main evaluation criterion. Analgesia Nociception Index (ANI) was monitored during simulation. Likert scale questionnaire was filled out after each simulation. RESULTS: For each task, TCT was significantly lower for SER and seniors than simulator-naive residents (P = 0.0163). After only 5 simulations, SER were able to reach and even exceed the seniors' level in terms of TCT, with a median time of 10.8 min for SER and 11.9 min for seniors, and wire's movements with a median distance during cannulation of 4.44 m for SER and 4.17 m for seniors. Seniors remained better than SER in terms of precise wire manipulation (wire movement after cannulation), 4.17 m against 4.44 m (3.72-5.96), respectively. Based on the Likert scale stress analysis, seniors felt less stressed than both residents' groups (P = 0.0618). Seniors' initial ANI and mean ANI over the session were significantly lower than those of the residents, P = 0.0358 and P = 0.0250, respectively. CONCLUSIONS: We showed that 5 simulation sessions allowed residents to reach experienced surgeons' capacities on FEVS concerning TCT. Subjectively, seniors felt less stressed than residents, contrary to the results of our objective measures of stress.

Sex-Specific Morphometric Analysis of Ascending Aorta and Aortic Arch for Planning Thoracic Endovascular Aortic Repair: A Retrospective Cohort Study.

OBJECTIVE: In many studies on aortic disease, women are underrepresented. The present study aims to assess sex-specific morphometric differences and gain more insight into endovascular treatment of the ascending aorta (AA) and arch. METHODS: Electrocardiogram-gated cardiac computed tomography scans of 116 consecutive patients who were evaluated for transcatheter aortic valve replacement were retrospectively reviewed. Measurements of the AA and aortic arch were made in multiplanar views, perpendicular to the semi-automatic centerline. Multiple linear regression analysis was performed to identify predictors affecting AA and aortic arch diameter in men and women. Propensity score matching was used to investigate whether sex influences aortic morphology. RESULTS: In both sexes, body surface area (BSA) was identified as a positive predictor and diabetes as a negative predictor for aortic diameters. In men, age was identified as a positive predictor and smoking as a negative predictor for aortic diameters. Propensity score matching identified 40 pairs. Systolic and diastolic mean diameters and AA length were significantly wider in men. On average, male aortas were 7.4% wider than female aortas, both in systole and diastole. CONCLUSIONS: The present analysis demonstrates that, in women, increased BSA is associated with increased aortic arch diameters, while diabetes is associated with decreased AA and arch diameters. In men, increased BSA and age are associated with increased AA and arch diameters, while smoking and diabetes are associated with decreased AA and arch diameters. Men were confirmed to have 7.4% greater AA and arch diameters than women. CLINICAL IMPACT: Men had 7.4% greater ascending aorta and arch diameters than women in a retrospective cohort, gated computed tomography-based study of 116 patients. Sex-specific differences in ascending aortic and arch size should be considered by aortic endovascular device manufacturers and physicians when developing ascending and arch endografts and planning aortic interventions.

StemRad MD, An Exoskeleton-Based Radiation Protection System, Reduces Ergonomic Posture Risk Based on a Prospective Observational Study.

OBJECTIVE: Poor ergonomic posture during interventional procedures might lead to increased physical discomfort and work-related musculoskeletal disorders. Adjunctive equipment such as lead aprons (LAs) has been shown to increase ergonomic posture risk (EPR). The objective of this study was to evaluate the effectiveness of StemRad MD (StemRad Ltd., Tel Aviv, Israel), a weightless exoskeleton-based radiation protective ensemble, in reducing EPR on the operator using wearable inertial measurement unit (IMU) sensors. METHODS: A prospective, observational study was conducted at an academic hospital. Inertial measurement unit sensors were affixed to the upper back of 9 interventionalists to assess ergonomic risk posture during endovascular procedures while wearing a traditional LA or the StemRad MD radiation protection system. Total fluoroscopy time, procedure type, and ergonomic risk postures were recorded and analyzed. RESULTS: Twenty-one cases were performed with StemRad MD and 30 with LAs. Mean procedure time for the StemRad MD procedures was 48.4±23.3 minutes (range: 24-106 min), and for LA procedures, it was 34.66±25.83 minutes (range: 6-100 min) (p=.060). The operators assumed low-risk ergonomic positions in 96.1% of StemRad MD cases and in 62.9% of LA cases (p=.001), and high-risk ergonomic positions in 0% and 6.2%, respectively (p=.80). Mean EPR score for StemRad MD was 1.16, and for the LA, it was 1.49 (p=.001). CONCLUSIONS: StemRad MD significantly reduces the EPR to the torso compared with a LA-based radiation protection system. CLINICAL IMPACT: Poor ergonomic posture during interventional procedures might leas to work-related musculoskeletal disorders for healthcare workers. StemRad MD, a weightless, exoskeleton-based radiation protection system was shown to significantly reduce ergonomic posture risk to the torso compared to conventional lead aprons. This might lead to reduced physical discomfort for procedure-based specialists.

Experimental Analysis of Radiation Protection Offered by a Novel Exoskeleton-Based Radiation Protection System versus Conventional Lead Aprons.

PURPOSE: To evaluate the radiation protection offered by an exoskeleton-based radiation protection system (Stemrad MD) and to compare it with that offered by conventional lead aprons. METHODS: The experimental setup involved 2 anthropomorphic phantoms, an operator, a patient, and a C-arm as the x-ray radiation source. Thermoluminescent detectors were used to measure radiation doses to different radiosensitive body parts on the operator phantom both with the exoskeleton and a conventional lead apron at the left radial and right femoral positions. Detected radiation doses for the exoskeleton and lead apron for different body parts and positions were compared. RESULTS: At the left radial position, the mean radiation dose (mGy) reduction by the exoskeleton compared with that by the lead apron was >90% for the left eye lens (0.22 ± 0.13 vs 5.18 ± 0.08; P < .0001), right eye lens (0.23 ± 0.13 vs 4.98 ± 0.10; P < .0001), left head (0.11 ± 0.16 vs 3.53 ± 0.07; P < .0001), right head (0.27 ± 0.09 vs 3.12 ± 0.10; P < .0001), and left brain (0.04 ± 0.08 vs 0.46 ± 0.07; P < .0001). At the right femoral position, radiation reduction was >90% for the left eye lens (0.14 ± 0.10 vs 4.16 ± 0.09; P < .0001), right eye lens (0.06 ± 0.08 vs 1.90 ± 0.11; P < .0001), left head (0.10 ± 0.08 vs 4.39 ± 0.08; P < .0001), left brain (0.03 ± 0.07 vs 1.44 ± 0.08; P < .0001), right brain (0.00 ± 0.14 vs 0.11 ± 0.13; P = .06), and thyroid (0.04 ± 0.07 vs 0.27 ± 0.09; P < .0001). Protection of the torso was equivalent to that offered by conventional lead aprons. CONCLUSIONS: The exoskeleton-based system provided superior radiation protection to the physician compared with that provided by conventional lead aprons. The effects are particularly impactful for the brain, eye lens, and head areas.

Editor's Choice - Trends in Management and Outcomes of Type B Aortic Dissection: A Report From the International Registry of Aortic Dissection.

OBJECTIVE: To describe the trends in management and outcomes of patients with acute type B aortic dissection in the International Registry of Acute Aortic Dissection. METHODS: From 1996 - 2022, 3 908 patients were divided into similar sized quartiles (T1, T2, T3, and T4). In hospital outcomes were analysed for each quartile. Survival rates following admission were compared using Kaplan-Meier analyses with Mantel-Cox Log rank tests. RESULTS: Endovascular treatment increased from 19.1% in T1 to 37.2% in T4 (ptrend < .001). Correspondingly, medical therapy decreased from 65.7% in T1 to 54.0% in T4 (ptrend < .001), and open surgery from 14.8% in T1 to 7.0% in T4 (ptrend < .001). In hospital mortality decreased in the overall cohort from 10.7% in T1 to 6.1% in T4 (ptrend < .001), as well as in medically, endovascularly and surgically treated patients (ptrend = .017, .033, and .011, respectively). Overall post-admission survival at three years increased (T1: 74.8% vs. T4: 77.3%; p = .006). CONCLUSION: Considerable changes in the management of acute type B aortic dissection were observed over time, with a significant increase in the use of endovascular treatment and a corresponding reduction in open surgery and medical management. These changes were associated with a decreased overall in hospital and three year post-admission mortality rate among quartiles.

"Octafen": A Noninvestigational Alternative Endograft Configuration for the Treatment of Thoracoabdominal Aortic Aneurysms.

PURPOSE: To demonstrate the feasibility of Octafen technique, a novel endovascular configuration for the treatment of thoracoabdominal aortic aneurysms (TAAA). TECHNIQUE: Two patients with complex TAAA and high surgical risk were treated with Octafen endograft configuration in a hybrid operating room with computed tomography (CT)-fluoroscopy image fusion guidance, using 3D-3D fusion techniques to facilitate procedural success. The procedure is a modification of the previously-described Octopus technique for endovascular repair of TAAA. The main advantage of this technique is the ability to use devices to repair a TAAA with the combination of off-the-shelf and noninvestigational custom-made devices. The devices used are readily available to most practicing vascular surgeons, which provides an alternative treatment in case of limited access to investigational devices, in time-sensitive cases, and in patients with limited functional capacity who cannot undergo open repair. In the modification described herein, we use a combination of standard bifurcated endovascular aneurysm repair (EVAR) devices (Excluder; W.L. Gore & Associates, Flagstaff, Arizona) in combination with a 2-vessel renal fenestrated device (Z-Fen; Cook Medical, Bloomington, Indiana). The article describes a step-by-step approach to this technique to elucidate pitfalls, benefits, and advantages. CONCLUSION: The Octafen technique might offer an alternative option for thoracoabdominal aneurysm treatment circumventing the need for access to custom-made, investigational devices. CLINICAL IMPACT: In this manuscript, we describe a technique for endovascular repair of thoraco-abdominal aortic aneurysms that involves the combination of off-the-shelf and non-investigational, custom-made devices. The 'Octafen' technique provides a treatment alternative in case of limited access to investigational devices and can be adjusted according to patient anatomy.

Endovascular Porcine Model of Iliocaval Venous Thrombosis.

OBJECTIVE: To develop a large animal model of iliocaval deep venous thrombosis (DVT), which enables development and evaluation of interventional management and existing imaging modalities. METHODS: The experimental protocol consisted of a total endovascular approach. Pigs were percutaneously accessed through the right internal jugular and bilateral femoral veins. Three balloon catheters were inflated to induce venous stasis in the infrarenal inferior vena cava (IVC) and bilateral common iliac veins (CIVs). Hypercoagulability was induced by injecting 10 000 IU of thrombin. After 2.5 hours, the balloon catheters were removed before animal recovery. After seven, 14, 21, 28, or 35 days, animals were euthanised; the IVC and CIV were harvested en bloc, cross sectioned and prepared for histological examination. Multimodal imaging was performed before and after thrombus creation, and before animal euthanasia. RESULTS: Thirteen female domestic pigs with a mean weight of 59.3 kilograms were used. The mean maximum IVC diameter and area were 16.4 mm and 1.2 cm2, respectively. The procedure was successful in 12 animals with occlusive venous thrombosis in the region of interest on immediate post-operative magnetic resonance venography and a mean thrombus volume of 19.8 cm3. Clinical pathology results showed platelet consumption, D dimer increase, and inflammatory response. Histological evaluation demonstrated a red cell, fibrin, and platelet rich thrombus on day 1, with progressive inflammatory cell infiltration from day 7. Collagen deposition appeared in week 2 and neovascularisation in week 3. CONCLUSION: Endovascular occlusion combined with thrombin infusion is a reliable minimally invasive approach to produce acute and subacute DVT in a large animal model.

Evaluating a Novel Telescoping Catheter Set for Treatment of Central Venous Occlusions.

BACKGROUND: Central venous occlusive disease (CVOD) is a prevalent problem in patients with end-stage renal disease (ESRD) and can lead to access malfunction or ligation for symptomatic relief. The purpose of this study is to evaluate the efficacy of the TriForce® Peripheral Crossing Set (Cook Medical), a novel reinforced telescoping catheter set designed to provide additional support for crossing difficult central venous occlusions. METHODS: This is a single-center retrospective study from a quaternary referral center. We identified 37 patients over a 17-month period who underwent 56 attempts at endovascular recanalization for the treatment of central venous occlusion. Technical success rates, procedural data, and outcomes were compared between those undergoing recanalization using traditional wire/catheter sets versus the TriForce catheter set. RESULTS: Average age was 48 ± 2 years. Comorbidities were similar between the two cohorts and included ESRD (61%), deep venous thrombosis (30%), and May-Thurner syndrome (7%). Forty attempts were made with traditional wire/catheter sets and 16 attempts with the TriForce catheter set to treat 2.1 ± 0.2 and 1.9 ± 0.3 occluded venous segments, respectively (P = 0.74). Technical success rates were significantly higher for the group undergoing recanalization using the TriForce catheter (69% versus 38%, P = 0.04) and 4 patients were successfully recanalized using the TriForce catheter set after a failed attempt with traditional wire/catheter sets. Mean fluoroscopy time and radiation dose were 13 ± 3 min and 14,623 ± 2,775 µGy∗m2 for traditional techniques versus 30 ± 6 min and 30,408 ± 10,433 µGy∗m2 for the novel telescoping catheter set (P = 0.01 and 0.09, respectively). Freedom from reintervention at 1 year was 60% for the TriForce cohort versus 44% for the traditional wire/catheter cohort (P = 0.25). CONCLUSIONS: The novel TriForce reinforced telescoping catheter set is a useful adjunct that may improve recanalization rates of CVOD compared with traditional wire/catheter sets.

In the Fundamentals of Endovascular and Vascular Surgery model motion metrics reliably differentiate competency.

OBJECTIVE: The Fundamentals of Endovascular and Vascular Surgery, a curriculum that includes an endovascular model for skills testing, aims to differentiate between competent and noncompetent performers. The aim of our study was to further validate the model and to test its reliability in assessing the performance of endovascular trainees in an uncontrolled setting. METHODS: The model was tested exclusively in a virtual reality environment. On the basis of their endovascular experience, 52 participants were divided into three groups: novice (<50 endovascular cases), intermediate (50-500 endovascular cases), and expert (>500 endovascular cases). Performance was evaluated in four tasks, measuring the tool tip position and velocity on the virtual model. Average tool tip velocity and movement smoothness in the velocity frequency domain are validated parameters defining proficiency of movement. The data were filtered and interpolated to calculate the metrics. Trials containing critical tool manipulation errors were excluded. RESULTS: In total, 52 tasks completed by novices, 25 completed by intermediates, and 38 completed by experts were analyzed to determine performance. The difference in performance between the novice and expert groups was statistically significant for guidewire smoothness (P < .001). The expert group had a statistically significantly higher average guidewire velocity compared with the novice group (P < .001). CONCLUSIONS: The Fundamentals of Endovascular and Vascular Surgery model continues to differentiate novices from experts on the basis of their handling of guidewire and catheter tools, measured as smoothness and velocity. This model offers a useful instrument to test competency of endovascular surgeons.

Three-Year Follow-up of Patients With Iliac Occlusive Disease Treated With the Viabahn Balloon- Expandable Endoprosthesis.

PURPOSE: To assess the midterm safety and effectiveness of the Gore Viabahn Balloon-Expandable Endoprosthesis (VBX Stent-Graft) in the treatment of patients with de novo or restenotic aortoiliac lesions. MATERIALS AND METHODS: The prospective, multicenter, nonrandomized, single-arm VBX FLEX clinical study (ClinicalTrials.gov identifier: NCT02080871) evaluated 134 patients (mean age 66±9.5 years; 79 men) up to 3 years after treatment with the VBX Stent-Graft. A total of 213 lesions were treated with 234 stent-grafts. The primary safety endpoint was a composite of major adverse events (MAEs), which were evaluated through 30 days and 9 months. Secondary outcomes collected through 3 years included freedom from target lesion revascularization (TLR), target vessel revascularization (TVR), clinically-driven TLR (CD-TLR), and CD-TVR as well as Rutherford category, resting ankle-brachial index (ABI), and functional status. A univariate analysis determined any correlation between baseline variables and TLR. RESULTS: The observed composite percentage of MAEs was 2.3%, well below the 17% performance goal (p<0.001). Of the 134 patients in the per protocol analysis, 107 (80%) completed the study. The 1-year Kaplan-Meier estimate of primary patency was 94.5% and primary assisted patency was 99.0%. The estimate of freedom from TLR per-lesion/vessel was 97.6% at 9 months and 91.2% at 3 years. The 9-month estimate of freedom from CD-TLR was 98.6% and the 3-year estimate was 98.1%. The 3-year mean resting ABI was 0.93±0.19, an improvement of 0.17±0.26 from baseline (p<0.001). At 3 years, 82 patients (92.1%) improved ≥1 Rutherford category from baseline, and 77 patients (86.5%) maintained or improved upon their baseline functional status. CONCLUSION: The VBX Stent-Graft is a robust and durable treatment option for aortoiliac occlusive disease as evidenced by the sustained 3-year safety and effectiveness outcomes.

Critical Review of Large Animal Models for Central Deep Venous Thrombosis.

OBJECTIVE: To review the existing literature on large animal models of central venous thrombosis (CVT) and to evaluate its relevance in regard to the development and testing of dedicated therapeutics applicable to humans. METHODS: A systematic literature search was conducted in PubMed and Embase. Articles describing an in vivo experimental protocol of CVT in large animals, involving the iliac vein and/or the vena cava and/or the brachiocephalic vein, were included. The primary aim of the study, animal characteristics, experimental protocol, and thrombus evaluation were recorded. RESULTS: Thirty-eight papers describing more than 30 different protocols were included. Animals used were pigs (53%), dogs (21%), monkeys (24%), and cattle (3%). The median number of animals per study was 12. Animal sex, strain, and weight were missing in 18 studies (47%), seven studies (18%), and eight studies (21%), respectively. CVT was always induced by venous stasis: solely (55%), or in addition to hypercoagulability (37%) or endothelial damage (10%). The size of the vessel used for thrombus creation was measured in four studies (10%). Unexpected animal death occurred in nine studies (24%), ranging from 3% to 37% of the animals. Twenty-two studies (58%) in the acute phase and 31 studies in the chronic phase (82%) evaluated the presence or absence of the thrombus created, and its occlusive characteristic was reported, respectively, in five and 17 studies. Histological examination was performed in 24 studies (63%) with comparison to human thrombus in one study. CONCLUSION: This review showed advantages and weaknesses of the existing large animal models of CVT. Future models should insist on more rigour and consistency in reporting animal characteristics, as well as evaluating and comparing the thrombus created to human thrombus.

Impact of Aortic Tortuosity on Displacement Forces in Descending Thoracic Aortic Aneurysms.

OBJECTIVE: As elastin fibres in the aorta deteriorate with age, the descending thoracic aorta (DTA) becomes longer and more tortuous. In patients with DTA aneurysms, this increased tortuosity may result in a hostile haemodynamic environment for thoracic endovascular aortic repair (TEVAR). The objective of this study was to analyse how increased tortuosity affects haemodynamic displacement forces (DFs) in different segments of the DTA in patients with DTA aneurysms (DTAAs). METHODS: Thirty patients with DTAAs were selected to form three equal groups based on the maximum tortuosity of their DTA: low < 30°, moderate 30°-60°, and high > 60°. Computational fluid dynamics simulations were performed to calculate DFs in all patients. Image based segmentations were carried out to create patient specific models of the aortic geometry. When physiological simulation results were obtained, the haemodynamic DFs on the aortic wall were calculated in four segments of the DTA (zones 4A - D). To enable comparison of DFs in different segments, the DF was normalised by the aortic wall surface area, the equivalent surface traction (EST). RESULTS: The mean age was 73 years, with 67% male. In zone 4C, where most tortuosity occurs, the EST in patients with high tortuosity was more than three times higher, than those with low tortuosity (low, 743 N/m2; moderate, 956 N/m2; high, 2294 N/m2; p = .004). These differences could be attributed to the higher sideways components of the DF vectors, which were more than two times greater in patients with high tortuosity than in patients with low or moderate tortuosity (low, 5.01 N; moderate, 5.50 N; high, 13.21 N; p = .009). CONCLUSION: High tortuosity results in increased displacement forces in the distal segments of the DTA. These forces should be taken into account when planning for TEVAR, as potentially they increase the risk of stent graft related complications, such as migration and endoleak.

Tortuosity of the Descending Thoracic Aorta in Patients with Aneurysm and Type B Dissection.

OBJECTIVE: Tortuosity in the descending thoracic aorta (DTA) comes with aging and increases the risk of endoleaks after TEVAR. With this report, we would like to define and classify tortuosity in the DTA of patients with thoracic aortic disease. METHODS: Retrospective case-control study of two hundred seven patients, comparing sixty-nine controls without aortic disease (CG), to sixty-nine patients with descending thoracic aortic aneurysm (AG) and sixty-nine patients with type B aortic dissection (DG). 3Mensio Vascular software was used to analyze CTA scans and collect the following measurements; tortuosity index, curvature ratio and the maximum tortuosity of the DTA. The DTA was divided into four equal zones. The maximum tortuosity was divided into three groups: low (<30°), moderate (30°-60°) and high tortuosity (>60°). RESULTS: Compared to the CG, tortuosity was more pronounced in the DG, and even more in the AG, evidenced by the tortuosity index (1.11 vs. 1.20 vs. 1.31; p < 0.001), curvature ratio (1.00 vs. 1.01 vs. 1.03; p < 0.001), maximum tortuosity in degrees (28.17 vs. 33.29 vs. 43.83; p < 0.001) and group of tortuosity (p < 0.001). The maximum tortuosity was further distal for the DG and AG, evidenced by the zone of maximum tortuosity (4A vs. 4B vs. 4B; p < 0.001). CONCLUSION: This study shows that tortuosity in the DTA is more prominent in diseased aortas, especially in aneurysmal disease. This phenomenon needs to be taken into account during planning of TEVAR to prevent stent graft-related complications and to obtain positive long-term outcome.

Type 1b Endoleaks After Thoracic Endovascular Aortic Repair are Inadequately Reported: A Systematic Review.

BACKGROUND: Complications after thoracic endovascular aortic repair (TEVAR) are common. Even after a successful TEVAR, a late endoleak (>30 days) can occur. The objective of this study is to summarize the current evidence and, if lacking, the need of evidence regarding the incidence and predictive factors for type 1b endoleak in patients with aortic aneurysm treated with TEVAR. METHODS: A systematic review of the literature was performed on endoleak type 1b, in patients with aortic aneurysm, after TEVAR. The PubMed and Embase databases were systematically searched for articles regarding endoleak type 1b up to January 2019. The main subjects discussed are the incidence, risk factors, treatment, and prognosis. RESULTS: About 722 articles were screened, and 16 articles were included in this review. The reported incidence of endoleak is between 1.0% and 15.0%, with a mean follow-up duration of at least 1 year. Type 1b endoleak is associated with an increased aortic tortuosity index (>0.15 cm-1). No significant difference is found in relation to age and gender. Treatment is required in most cases (22/27) and is usually performed with distal extension of the stent graft (21/27). There are no data regarding stent graft oversizing, length of distal landing zone, and differences between devices or the prognosis for patients with type 1b endoleak. CONCLUSIONS: Limited literature is available on the occurrence of type 1b endoleak after TEVAR. A tortuous aorta can be associated as a predictive factor for the occurrence of type 1b endoleak. Data clearly delineating the anatomic variables predicting type 1b endoleak should be examined and listed. Likewise, the impact of more recent conformable devices to prevent complications like type 1b endoleaks from occurring should be elucidated.

Clinical Experience with the Gore Hybrid Vascular Graft in Complex Revascularizations Demonstrates Safety and Efficacy.

BACKGROUND: Arterial revascularizations can present significant challenges when vessels are disadvantaged and advances in technology present the surgeon with innovative opportunities. A number of studies have used the GORE® Hybrid Vascular Graft (GHVG), and we have been using this device in arterial revascularizations since it came to market. The aim of this study is therefore to present a large single-center experience using the GHVG. This series presents patients with complex revascularizations in multiple vascular beds. METHODS: We retrospectively analyzed a single-center series of 43 patients who received a total of 56 GHVGs in complex revascularization procedures at Houston Methodist Hospital from March 2012 to April 2017. We excluded 5 patients (7 grafts in total) because of loss of follow-up. An additional 8 patients were excluded from the analysis (11 grafts in total) secondary to mortalities unrelated to their grafts (7 patients died during index hospitalization and 1 patient died shortly after discharge). RESULTS: Our results demonstrated an 18-month primary patency, assisted primary patency, and secondary patency of 82, 86, and 96%, respectively. These complex revascularizations included a total of 56 devices placed. GHVGs were placed in the external iliac artery (27/56), renal artery (12/56), common femoral artery (6/56), superficial femoral artery (4/56), common iliac artery (3/56), grafts (3/56), profunda femoris artery (1/56), and the superior mesenteric artery (1/56). Early mortality in patients (7/8) was because of the nature of their disease and not related to the surgical intervention. CONCLUSIONS: The GHVG has the ability to create a sutureless anastomosis in a disadvantaged vessel or to promote a potentially better outcome by either avoiding prolonged ischemia to visceral branches or avoiding extensive abdominal or retroperitoneal exposure in an iliofemoral bypass. These results demonstrate the value of the GHVG in complex revascularizations not amenable to traditional open surgical bypass. LEVEL OF EVIDENCE: IV.

Impact of Cardiac Cycle on Thoracic Aortic Geometry-Morphometric Analysis of Ecg Gated Computed Tomography.

BACKGROUND: Understanding morphological changes of ascending aorta, aortic arch and descending aorta with cardiac and respiratory motion is critical for planning of endovascular repair of thoracic aorta. The aim of this study was to determine the impact of the cardiac cycle on thoracic aortic geometry. METHODS: In this retrospective study, electrocardiogram-gated cardiac computed tomography from 116 patients who were evaluated for transcatheter aortic valve replacement were reviewed. A protocol for measurements of maximal diameters and lengths of the thoracic aorta and supra-aortic vessels was established. Measurements were made in multiplanar views perpendicular to the semiautomatically created centerline on both systolic and diastolic phases. RESULTS: Mean age was 77 ± 11 years of our study cohort. Mean systolic and diastolic diameter were 31.6 ± 0.42 and 30.1 ± 4.4 mm at the sinotubular junction (STJ), 35.6 ± 4.8 and 34.8 ± 4.7 mm in the ascending aorta, 29.1 ± 3.3 and 28.5 ± 3.3 mm in the aortic arch (distal left common carotid artery), and 26.7 ± 5.4 and 25.8 ± 5.4 mm in the descending aorta. Mean diameter change was 1.5 ± 0.9 mm at the STJ, 0.8 ± 0.9 mm in the ascending aorta, 0.6 ± 0.8 mm in the aortic arch, and 0.9 ± 1.2 mm in the descending aorta. Mean arterial strain was 5.0 ± 3.2% at the level of the STJ, 2.4 ± 2.7% in the ascending aorta, 2.0 ± 2.9% in the aortic arch, and 3.9 ± 5.7% in the descending aorta. CONCLUSIONS: Our results demonstrated that small but significant circumferential and longitudinal strain was present at every aortic level. These findings may have implications for endovascular thoracic aortic repair and may provide reference values for future comparison.

Proposed Magnetic Resonance Imaging Criteria to Diagnose Intramural Haematoma and to Predict Aortic Healing after Acute Type B Aortic Syndrome.

OBJECTIVE: Type B acute aortic syndrome (AAS) encompasses aortic dissection (AD) and intramural haematoma (IMH), the diagnosis, evolution, and treatment of which are subject to controversies. The aim of this pilot investigation was to assess the ability of specific magnetic resonance imaging (MRI) criteria to differentiate AD from IMH and predict optimal aortic remodeling following AAS. METHODS: In this retrospective study, all patients presenting between 2008 and 2015 with type B AAS, who had diagnostic MRI following admission, were included. Three MRI criteria were proposed to identify IMH: (i) no visualised entry tear; (ii) no contrast uptake in the aortic lesion on the first pass angiographic run; (iii) no contrast uptake in the aortic lesion on the equilibrium phase T1 sequence. On each patient's diagnostic and follow up imaging studies, the volume of (i) false lumen/IMH, (ii) total aorta, and (iii) true lumen were calculated. Using the Wilcoxon signed rank test, the evolution of these volumes according to the presence or absence of the aforementioned criteria were compared. RESULTS: Of 39 patients, in seven all MRI criteria were positive (group IMH) and 32 had one or more negative criteria (group AD). Patients with IMH and AD were similar with respect to sex, age, and delay between onset of symptoms and diagnostic and follow up imaging studies. Eighteen patients had a follow up imaging study after a mean period of 11.2 months: six in the IMH group and 12 in the AD group. Lesion volume decrease and relative true lumen volume increase were statistically significant in group IMH (p = .046 and p = .046, respectively), whereas there was a statistically significant increase of lesion volume (p = .008) in the AD group. CONCLUSION: This pilot study proposed three simple MRI criteria to differentiate between AD and IMH. Once prospectively and clinically validated, this could have substantial therapeutic benefits as IMH are likely to heal spontaneously.

Computed tomography angiography-fluoroscopy image fusion allows visceral vessel cannulation without angiography during fenestrated endovascular aneurysm repair.

BACKGROUND: Fenestrated endovascular aneurysm repair (FEVAR) is an evolving technique to treat juxtarenal abdominal aortic aneurysms (AAAs). Catheterization of visceral and renal vessels after the deployment of the fenestrated main body device is often challenging, usually requiring additional fluoroscopy and multiple digital subtraction angiograms. The aim of this study was to assess the clinical utility and accuracy of a computed tomography angiography (CTA)-fluoroscopy image fusion technique in guiding visceral vessel cannulation during FEVAR. METHODS: Between August 2014 and September 2016, all consecutive patients who underwent FEVAR at our institution using image fusion guidance were included. Preoperative CTA images were fused with intraoperative fluoroscopy after coregistering with non-contrast-enhanced cone beam computed tomography (syngo 3D3D image fusion; Siemens Healthcare, Forchheim, Germany). The ostia of the visceral vessels were electronically marked on CTA images (syngo iGuide Toolbox) and overlaid on live fluoroscopy to guide vessel cannulation after fenestrated device deployment. Clinical utility of image fusion was evaluated by assessing the number of dedicated angiograms required for each visceral or renal vessel cannulation and the use of optimized C-arm angulation. Accuracy of image fusion was evaluated from video recordings by three raters using a binary qualitative assessment scale. RESULTS: A total of 26 patients (17 men; mean age, 73.8 years) underwent FEVAR during the study period for juxtarenal AAA (17), pararenal AAA (6), and thoracoabdominal aortic aneurysm (3). Video recordings of fluoroscopy from 19 cases were available for review and assessment. A total of 46 vessels were cannulated; 38 of 46 (83%) of these vessels were cannulated without angiography but based only on image fusion guidance: 9 of 11 superior mesenteric artery cannulations and 29 of 35 renal artery cannulations. Binary qualitative assessment showed that 90% (36/40) of the virtual ostia overlaid on live fluoroscopy were accurate. Optimized C-arm angulations were achieved in 35% of vessel cannulations (0/9 for superior mesenteric artery cannulation, 12/25 for renal arteries). CONCLUSIONS: Preoperative CTA-fluoroscopy image fusion guidance during FEVAR is a valuable and accurate tool that allows visceral and renal vessel cannulation without the need of dedicated angiograms, thus avoiding additional injection of contrast material and radiation exposure. Further refinements, such as accounting for device-induced aortic deformation and automating the image fusion workflow, will bolster this technology toward optimal routine clinical use.

Electromagnetic tracking of flexible robotic catheters enables "assisted navigation" and brings automation to endovascular navigation in an in vitro study.

OBJECTIVE: Combining three-dimensional (3D) catheter control with electromagnetic (EM) tracking-based navigation significantly reduced fluoroscopy time and improved robotic catheter movement quality in a previous in vitro pilot study. The aim of this study was to expound on previous results and to expand the value of EM tracking with a novel feature, assistednavigation, allowing automatic catheter orientation and semiautomatic vessel cannulation. METHODS: Eighteen users navigated a robotic catheter in an aortic aneurysm phantom using an EM guidewire and a modified 9F robotic catheter with EM sensors at the tip of both leader and sheath. All users cannulated two targets, the left renal artery and posterior gate, using four visualization modes: (1) Standard fluoroscopy (control). (2) 2D biplane fluoroscopy showing real-time virtual catheter localization and orientation from EM tracking. (3) 2D biplane fluoroscopy with novel EM assisted navigation allowing the user to define the target vessel. The robotic catheter orients itself automatically toward the target; the user then only needs to advance the guidewire following this predefined optimized path to catheterize the vessel. Then, while advancing the catheter over the wire, the assisted navigation automatically modifies catheter bending and rotation in order to ensure smooth progression, avoiding loss of wire access. (4) Virtual 3D representation of the phantom showing real-time virtual catheter localization and orientation. Standard fluoroscopy was always available; cannulation and fluoroscopy times were noted for every mode and target cannulation. Quality of catheter movement was assessed by measuring the number of submovements of the catheter using the 3D coordinates of the EM sensors. A t-test was used to compare the standard fluoroscopy mode against EM tracking modes. RESULTS: EM tracking significantly reduced the mean fluoroscopy time (P < .001) and the number of submovements (P < .02) for both cannulation tasks. For the posterior gate, mean cannulation time was also significantly reduced when using EM tracking (P < .001). The use of novel EM assisted navigation feature (mode 3) showed further reduced cannulation time for the posterior gate (P = .002) and improved quality of catheter movement for the left renal artery cannulation (P = .021). CONCLUSIONS: These results confirmed the findings of a prior study that highlighted the value of combining 3D robotic catheter control and 3D navigation to improve safety and efficiency of endovascular procedures. The novel EM assisted navigation feature augments the robotic master/slave concept with automated catheter orientation toward the target and shows promising results in reducing procedure time and improving catheter motion quality.