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1.
J Vasc Surg Venous Lymphat Disord ; : 101895, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38679142

RESUMO

OBJECTIVE: Iliocaval thrombotic obstruction is a challenging condition, especially since thrombus age and corresponding pathological remodeling at presentation are unknown, which directly impacts management. Our aim was to assess the ability of Magnetic Resonance Imaging (MRI) in determining age thresholds of experimentally created inferior vena cava (IVC) thrombosis in pigs. METHODS: We used a previously described swine model of IVC thrombosis. Animals underwent MRI at baseline, immediately after thrombosis creation and after a follow-up period extending from 2 to 28 days. Thirteen animals were divided into 3 groups according to disease's chronicity: acute (AG, N1 = 5), subacute (SAG, N2 = 4) and chronic group (CG, N3 = 4) with a mean thrombosis age of respectively 6.4 ± 2.5, 15.7 ± 2.8 and 28 ± 5.7 days. A T1 weighted volumetric interpolated breath-hold examination sequence was used to anatomically delineate IVC thrombus as a region of interest. Three other MRI sequences were used to assess thrombus signal. RESULTS: Kruskal-Wallis showed a statistically significant difference in T1 relaxation times after contrast injection (P = .026) between the 3 groups of chronicity: AG (360.2 ± 102.5) was significantly different from CG (336.7 ± 55.2 ms; P = .003) and SAG (354.1 ± 89.7 ms) was significantly different from AG (P = .027). There was a statistically significant difference in native T2 relaxation times (P = .038) between the 3 groups: AG (160 ± 86.7 ms) was significantly different from SAG (142.3 ± 55.4 ms; P = .027) and SAG was significantly different from CG (178.4 ± 11.7 ms; P = .004). CONCLUSIONS: This study highlighted MRI characteristics in a swine model that may have the potential to significantly differentiate a subacute and a chronic stage from an acute stage of deep venous thrombosis in humans. Further clinical studies in humans are warranted.

3.
Eur J Vasc Endovasc Surg ; 63(4): 623-630, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35272950

RESUMO

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.


Assuntos
Procedimentos Endovasculares , Trombose Venosa , Animais , Modelos Animais de Doenças , Procedimentos Endovasculares/métodos , Feminino , Humanos , Veia Ilíaca/diagnóstico por imagem , Veia Ilíaca/cirurgia , Stents , Suínos , Trombina , Resultado do Tratamento , Grau de Desobstrução Vascular/fisiologia , Veia Cava Inferior/diagnóstico por imagem , Veia Cava Inferior/cirurgia , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/etiologia , Trombose Venosa/terapia
4.
Int Angiol ; 40(3): 222-228, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33660497

RESUMO

INTRODUCTION: Radiation-induced arteriopathy (RIA) is a rare complication but may become more common due to the increased use of radiotherapy and the prolonged survival of patients. There is still a lack of evidence concerning treatment options. The aim of this study is to review reported cases of lower-limb RIA in order to provide guidelines for management. EVIDENCE ACQUISITION: We reported 4 cases treated for lower limb RIA and performed a systematic literature review without time limitation in the Medline database using the MeSh tems "iliac artery/radiation effects" OR "femoral artery/radiation effects." Main outcomes of interest were radiation dose, time before symptoms, symptoms, involved vessels, treatment and outcome. EVIDENCE SYNTHESIS: Twenty-five studies were included, reporting a total of 43 patients. Median time between irradiation and symptoms was 12 years (range: 9 days-49 years), with a median irradiation dose of 40Gy. Clinical presentation was claudication in 18 patients (52%), critical limb threatening ischemia (CLTI) in 4 patients (11%), acute limb ischemia (ALI) in 3 patients (9%) and hemorrhage in 6 patients (17%), the remaining 4 patients were asymptomatic (11%). Vessels involved were iliac arteries in 65% of the cases, femoropopliteal arteries in 28% of cases and concomitant supra and infrainguinal vessels in 7% of the cases. Claudication was mostly treated by open surgery (62%). Treatment of CLTI included primary amputation (50%), open surgery (25%) or endovascular surgery (25%). ALI was treated medically (33%), by open surgery (33%) or in situ thrombolysis (33%). Hemorrhagic cases or pulsatile masses were mostly treated by open surgery (66%). Follow-up was reported in 26 patients (67%), with mean follow-up of 12 months (range: 2 weeks - 5 years). During follow-up, 16% of these patients presented a recurrence of symptoms, and 8% required a reintervention. CONCLUSIONS: There seems to be no evidence for open versus endovascular treatment, but close and long-term follow-up is needed in these patients due to the possible late presentation and recurrence of symptoms after treatment.


Assuntos
Doença Arterial Periférica , Amputação Cirúrgica , Humanos , Claudicação Intermitente/etiologia , Claudicação Intermitente/terapia , Isquemia/cirurgia , Isquemia/terapia , Salvamento de Membro , Extremidade Inferior , Doença Arterial Periférica/cirurgia , Doença Arterial Periférica/terapia , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
5.
Ann Vasc Surg ; 72: 383-389, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32890642

RESUMO

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.


Assuntos
Procedimentos Endovasculares/instrumentação , Dispositivos de Acesso Vascular , Doenças Vasculares/terapia , Veias , Obstrução do Cateter , Cateterismo Venoso Central/efeitos adversos , Constrição Patológica , Procedimentos Endovasculares/efeitos adversos , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Doenças Vasculares/diagnóstico por imagem , Doenças Vasculares/etiologia , Doenças Vasculares/fisiopatologia , Grau de Desobstrução Vascular , Veias/diagnóstico por imagem , Veias/fisiopatologia
6.
Eur J Vasc Endovasc Surg ; 61(1): 146-154, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33187923

RESUMO

OBJECTIVE: To co-register conventional computed tomography angiography (CTA), with ex vivo micro-computed tomography (microCT) and histology of popliteal atherosclerotic plaques. Improving the non-invasive imaging capabilities may be valuable to advance patient care with peripheral arterial obstructive disease towards lesion and individual based treatment. METHODS: In this prospective observational study, 12 popliteal arteries from 11 symptomatic patients who had undergone transfemoral amputations for chronic limb threatening ischaemia and who had pre-operative CTA, were analysed ex vivo by microCT and histology. A total of 353 histological cross sections were co-registered with microCT and CTA, and classified as: lipid rich (LP, n = 26), fibrous (FP, n = 80), or calcific (CP, n = 247) plaques. CTA and microCT plaque density was calculated in 791 regions of interest as Hounsfield units (HU). RESULTS: CTA and microCT could identify plaque components that were confirmed by histology such as fibrous tissue (FP), lipid pool/core (LP), and calcification (CP). MicroCT densities were 77.8 HU for FP (IQR 52.8, 129.5 HU), -28.4 HU for LP (IQR -87.1, 13.2 HU), and 3826.0 HU for CP (IQR 2989.0, 4501.0 HU). CTA densities of the three components of the plaque were: 78.0 HU for FP (IQR 59.5, 119.8 HU), 32.5 HU for LP (IQR 15.0, 42 HU), and 641.5 HU for CP (IQR 425.8, 1135 HU). The differences were statistically significant between the HU densitometric characteristics among the three groups (p < .0001) for both imaging modalities. Overall, microCT performed better diagnostically than conventional CTA for the three types of plaques: areas under the receiving operator characteristics curve were greater for microCT than CTA for FP (0.97 vs. 0.90), for LP (0.88 vs. 0.67), and for CP (0.97 vs. 0.90). CONCLUSION: CTA and microCT can be used to identify histological atherosclerotic plaque components, with better diagnostic performance for microCT. This study demonstrates the feasibility of using microCT to assess plaque morphology lesions in a manner that approaches histology thus becoming a useful tool for ex vivo assessment of atherosclerosis and towards lesion based treatment.


Assuntos
Angiografia por Tomografia Computadorizada , Isquemia/diagnóstico por imagem , Doença Arterial Periférica/diagnóstico por imagem , Placa Aterosclerótica/diagnóstico por imagem , Microtomografia por Raio-X , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Angiografia por Tomografia Computadorizada/métodos , Feminino , Humanos , Isquemia/patologia , Perna (Membro)/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/patologia , Placa Aterosclerótica/patologia , Artéria Poplítea/diagnóstico por imagem , Artéria Poplítea/patologia , Estudos Prospectivos , Microtomografia por Raio-X/métodos
7.
Eur J Vasc Endovasc Surg ; 60(2): 243-252, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32359973

RESUMO

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.


Assuntos
Veias Braquiocefálicas , Veia Ilíaca , Veias Cavas , Trombose Venosa , Animais , Coagulação Sanguínea , Veias Braquiocefálicas/patologia , Modelos Animais de Doenças , Cães , Haplorrinos , Humanos , Veia Ilíaca/patologia , Especificidade da Espécie , Sus scrofa , Veias Cavas/patologia , Trombose Venosa/sangue , Trombose Venosa/etiologia , Trombose Venosa/patologia , Trombose Venosa/terapia
8.
J Cardiovasc Surg (Torino) ; 61(4): 402-415, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32337939

RESUMO

This article reviews endovascular management of chronic post-dissection aneurysms of the aortic arch. Therapeutic strategies intended for this complex aortic condition are evolving rapidly to allow the treatment of various hostile aortic anatomy and frail patients. Principles, technical considerations, devices and outcomes of each technique are reviewed and summarized. Hybrid repair offer similar early mortality and stroke rates compared to open conventional surgery. Arch chimney and other parallel graft techniques present poor long term outcome, and should be limited to emergency situations where no other option is available. Fenestrated stent-grafting is subjected to many technical challenges in aortic arch due to difficulties in stent-graft orientation and fenestration positioning. In situ fenestration is an off-label technique that should only be used as an emergency bailout maneuver, considering that temporary coverage of supra aortic trunk vessel and its long-term durability raise concern. Finally, in experienced hands and appropriate anatomic conditions, arch branched graft technology has shown itself to be a safe and effective alternative to open conventional surgery. No randomized controlled trials have yet compared total endovascular aortic arch repair with hybrid techniques and open arch repair. The management of chronic post-dissection aneurysms of the aortic arch is challenging, decision-making and interventions should continue to be performed in high-volume centers with a dedicated aortic team with an expertise in both open and endovascular repairs.


Assuntos
Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular/métodos , Prótese Vascular , Procedimentos Endovasculares , Doença Crônica , Humanos
9.
JACC Cardiovasc Interv ; 13(4): 418-427, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-32081234

RESUMO

OBJECTIVES: The objective of this study was to comprehensively evaluate the pathology of acute and chronic femoral stenting in symptomatic atherosclerotic patients and to understand the causes of stent failure (SF) using multimodality imaging including micro-computed tomography. BACKGROUND: Although the pathology of coronary stenting has been well studied, the pathology of lower extremity femoral stenting remains poorly understood. METHODS: Twelve stented femoral lesions removed at surgery (n = 10) and at autopsy (n = 2) were obtained from 10 patients (median age 74 years; interquartile range [IQR]: 66 to 82 years) with histories of peripheral artery disease (critical limb ischemia in 7) (7 men and 3 women). All specimens underwent radiography, micro-computed tomography, and histological assessment. RESULTS: The median duration of implantation was 150 days (IQR: 30 to 365 days), the median stent diameter was 5.90 mm (IQR: 5.44 to 7.16 mm), and the median stent length was 39.5 mm (IQR: 27 to 107.5 mm). Of the 12 stented lesions, 2 had drug-eluting stents, and 10 had bare-metal stents. SF was observed in 8 of 12 lesions. The major cause of SF was acute thrombosis (6 of 8), but causes varied (delayed healing, stent underexpansion, false lumen stenting, and fracture), and 2 had restenosis. Stent fractures were observed in 3 cases by micro-computed tomography. Both drug-eluting stents, implanted for >1 year, showed delayed healing with circumferential peristrut fibrin deposition and SF. CONCLUSIONS: This histological study is the first to examine the pathological cause of SF. Stent thrombosis was the major cause of SF. Delayed healing was a common feature of bare-metal stents implanted for <90 days, while all drug-eluting stents, despite implantation duration >1 year, showed delayed healing.


Assuntos
Procedimentos Endovasculares/instrumentação , Artéria Femoral , Isquemia/terapia , Imagem Multimodal , Doença Arterial Periférica/terapia , Falha de Prótese , Stents , Calcificação Vascular/terapia , Idoso , Idoso de 80 Anos ou mais , Remoção de Dispositivo , Procedimentos Endovasculares/efeitos adversos , Feminino , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/patologia , Artéria Femoral/cirurgia , Humanos , Isquemia/diagnóstico por imagem , Isquemia/patologia , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/patologia , Valor Preditivo dos Testes , Trombose/diagnóstico por imagem , Trombose/patologia , Fatores de Tempo , Resultado do Tratamento , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/patologia , Cicatrização , Microtomografia por Raio-X
11.
Ann Vasc Surg ; 65: 174-182, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31678128

RESUMO

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.


Assuntos
Aorta Torácica/diagnóstico por imagem , Aortografia , Técnicas de Imagem de Sincronização Cardíaca , Angiografia por Tomografia Computadorizada , Eletrocardiografia , Hemodinâmica , Idoso , Idoso de 80 Anos ou mais , Aorta Torácica/fisiopatologia , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Estudos Retrospectivos
13.
Eur J Vasc Endovasc Surg ; 57(3): 350-359, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30377034

RESUMO

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.


Assuntos
Aneurisma Aórtico/diagnóstico por imagem , Hematoma/diagnóstico por imagem , Angiografia por Ressonância Magnética , Cicatrização , Idoso , Aneurisma Aórtico/fisiopatologia , Aneurisma Aórtico/terapia , Diagnóstico Diferencial , Feminino , Hematoma/fisiopatologia , Hematoma/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Valor Preditivo dos Testes , Estudos Retrospectivos , Síndrome , Fatores de Tempo , Resultado do Tratamento
15.
Methodist Debakey Cardiovasc J ; 14(3): 208-213, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30410651

RESUMO

There is a growing need for dedicated endovascular devices to treat pathologies affecting the venous system. However, because of a lack of research into venous diseases and treatments, the optimal design, material, and mechanical properties of venous stents remain unknown. Development of the ideal venous stent should be based on a thorough understanding of the underlying venous pathology. There are multiple venous diseases that differ from each other depending on their location (iliocaval, superior vena cava), mechanism (thrombotic versus nonthrombotic lesions), and chronicity. Thus, it is likely that stent material, design, and features should differ according to each underlying disease. From a mechanical point of view, the success of a venous stent hinges on its ability to resist crushing (which requires high global and local radial rigidity) and to match with the compliant implant environment (which requires high flexibility). Device oversizing, textile coverage, and drug coating are additional features that should be considered in the context of venous diseases rather than directly translated from the arterial world. This review examines the unique forces affecting venous stents, the problems with using arterial devices to treat venous pathologies, preliminary results of a study comparing crush resistance of commercially available laser-cut stents with a novel braided stent design, and its applicability to venous interventions.


Assuntos
Procedimentos Endovasculares/instrumentação , Stents , Doenças Vasculares/cirurgia , Veias/cirurgia , Animais , Procedimentos Endovasculares/efeitos adversos , Hemodinâmica , Humanos , Desenho de Prótese , Falha de Prótese , Estresse Mecânico , Resultado do Tratamento , Doenças Vasculares/diagnóstico por imagem , Doenças Vasculares/fisiopatologia , Veias/diagnóstico por imagem , Veias/fisiopatologia
17.
J Vasc Surg ; 68(1): 2-11, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29395427

RESUMO

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.


Assuntos
Aorta Abdominal/diagnóstico por imagem , Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/cirurgia , Aortografia/métodos , Implante de Prótese Vascular/métodos , Cateterismo Periférico/métodos , Angiografia por Tomografia Computadorizada , Procedimentos Endovasculares/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Vísceras/irrigação sanguínea , Idoso , Pontos de Referência Anatômicos , Implante de Prótese Vascular/efeitos adversos , Cateterismo Periférico/efeitos adversos , Tomografia Computadorizada de Feixe Cônico , Procedimentos Endovasculares/efeitos adversos , Feminino , Fluoroscopia , Humanos , Masculino , Imagem Multimodal , Variações Dependentes do Observador , Valor Preditivo dos Testes , Punções , Reprodutibilidade dos Testes , Estudos Retrospectivos , Texas , Resultado do Tratamento , Gravação em Vídeo
18.
J Vasc Surg ; 67(4): 1274-1281, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28583735

RESUMO

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.


Assuntos
Aneurisma Aórtico/cirurgia , Cateterismo Periférico/instrumentação , Fenômenos Eletromagnéticos , Procedimentos Endovasculares/instrumentação , Radiografia Intervencionista/instrumentação , Procedimentos Cirúrgicos Robóticos/instrumentação , Dispositivos de Acesso Vascular , Aneurisma Aórtico/diagnóstico por imagem , Automação , Desenho de Equipamento , Fluoroscopia , Humanos , Modelos Anatômicos , Duração da Cirurgia , Imagens de Fantasmas
19.
Comput Biol Med ; 86: 6-17, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28494383

RESUMO

Centerlines of blood vessels are useful tools to make important anatomical measurements (length, diameter, area), which cannot be accurately obtained using 2D images. In this paper a brand new method for centerline extraction of vascular trees is presented. By using computational fluid dynamics (CFD) we are able to obtain a robust and purely functional centerline allowing us to support better measurements than classic purely geometrical-based centerlines. We show that the CFD-based centerline is within a few pixels from the geometrical centerline where the latter is defined (far away from inlet/outlets and from the branches). We show that the centerline computed with our method is not affected by traditional errors of other classical volume-based algorithms such as topological thinning, and could be a potential alternative to be considered for future studies.


Assuntos
Algoritmos , Aorta/fisiologia , Simulação por Computador , Hemodinâmica/fisiologia , Modelos Cardiovasculares , Aorta/anatomia & histologia , Humanos
20.
Methodist Debakey Cardiovasc J ; 13(1): 34-36, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28413581

RESUMO

Although anticoagulation remains the mainstay of therapy for patients with venous thromboembolism, guidelines recommend the use of inferior vena cava (IVC) filters in those who fail anticoagulation or have contraindications to its use. Short-term use of filters has proven effective in reducing the rate of pulmonary embolism. However, their extended use is associated with a variety of complications such as thrombosis, filter migration, or caval perforation, thus making a case for timely filter retrieval. This is the case of a 68-year-old female with a history of chronic oral anticoagulation use for multiple deep venous thrombi (DVT) and pulmonary emboli (PE) who required cervical and thoracic spinal intervention for spondylosis and foramina stenosis. Given her increased risk of recurrent DVT and PE perioperatively, we elected to place a Cook Celect™ IVC filter (Cook Medical, Bloomington, IN) after oral anticoagulation was stopped for the procedure. Her treatment course was prolonged due to wound-healing complications. We elected to use the Magellan Robotic Catheter System (Hansen Medical, Mountain View, CA) for filter retrieval when she presented 6 months later with caval perforation from the filter struts. With its ease of use, superior mechanical stability, and maneuverability, robot-assisted IVC filter retrieval may be a safer and more reliable substitute for traditional navigation techniques when presented with challenging filter retrievals.


Assuntos
Remoção de Dispositivo/métodos , Procedimentos Endovasculares , Implantação de Prótese/instrumentação , Robótica , Filtros de Veia Cava , Veia Cava Inferior , Tromboembolia Venosa/terapia , Idoso , Feminino , Humanos , Desenho de Prótese , Radiografia Intervencionista , Resultado do Tratamento , Veia Cava Inferior/diagnóstico por imagem , Tromboembolia Venosa/diagnóstico por imagem
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