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1.
S D Med ; 74(2): 70-74, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34161687

RESUMEN

INTRODUCTION: Pulmonary embolism (PE) is a significant disease process that affects an estimated 117 cases per 100,000 person-years. Chronic pulmonary hypertension (CPH) is a long-term complication associated with acute PE which has a significant cost to treat, ranging from $98,000-117,000. METHODS: A retrospective chart review of 341 patients from January 2011 to November 2018 who presented with massive or submassive PE and were treated with either systemic heparin therapy or catheter directed thrombolysis (CDT). The results of the short-term cost analysis and pulmonary hypertension rates from data collected was then used in a long-term cost model using a standardized 100 patient model. RESULTS: Treatment with CDT resulted in fewer bleeding complications (4.2 percent vs. 13.8 percent, p=0.005), a shorter length of stay, a greater percentage of patients returning to their prior living conditions (89.0 percent vs. 79.3 percent, p=0.042), and a lower rate of chronic pulmonary hypertension at 12 months (6.3 percent vs. 15.9 percent, p=0.030) than those treated with systemic heparin. The expense of treatment utilizing CDT was greater than those undergoing systemic heparin treatment with a difference of approximately $31,000 (p=0.001) though our cost model showed the heparin group to have a higher cost over time. CONCLUSIONS: For patients with massive or submassive PE, this study demonstrated a significant long-term cost savings and improved outcomes for patients treated with catheter directed thrombolysis when compared to systemic heparin administration.


Asunto(s)
Hipertensión Pulmonar , Embolia Pulmonar , Catéteres , Costos y Análisis de Costo , Heparina/uso terapéutico , Humanos , Hipertensión Pulmonar/tratamiento farmacológico , Embolia Pulmonar/tratamiento farmacológico , Estudios Retrospectivos , Terapia Trombolítica , Resultado del Tratamiento
2.
J Vasc Surg ; 72(6): 1897-1905.e2, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32335306

RESUMEN

OBJECTIVE: In the present study, we reviewed the 30-day and 1-year clinical results of the use of the investigational unitary manifold (UM) stent graft system (Sanford Health, Sioux Falls SDak) for the repair of Crawford type IV, pararenal, paravisceral, juxtarenal, and short-neck infrarenal aneurysms (<10 mm). METHODS: The present study was a single-center, multiarm, prospective review of the first 44 patients who had undergone repair of Crawford type IV, pararenal, juxtarenal, and short-neck infrarenal aneurysms (<10 mm) using the physician-modified UM under a physician-sponsored investigational device exemption. The primary end point was freedom from major adverse events at 30 days, including all-cause mortality, myocardial infarction, stroke, paraplegia, bowel ischemia, respiratory failure, and renal failure. RESULTS: Technical success was achieved in all 44 patients (100%), with a large number of these patients having undergone previous aortic repair (20 of 44; 45.5%). All the intended 170 visceral vessels (100%) had been successfully cannulated and stent grafted. No episodes of paraplegia or in-hospital deaths were recorded. One patient had died of aneurysm-related ischemic stroke (2.3%). The rate of transient nonclinically significant spinal cord ischemia was 4.5%. At the last follow-up, one reintervention had been required owing to branch patency from a thrombotic event. Of the 170 bridging stent grafts, 169 have remained patent through a mean follow-up of 8.8 months (range, 0-36 months). No type I or III endoleaks, migration, or component separation in the investigational device has occurred. CONCLUSIONS: The early and midterm results with the use of the UM suggest it could be a viable option for the repair of Crawford type IV, pararenal, paravisceral, juxtarenal, and short-neck infrarenal aneurysms (<10 mm) without exposing patients to the increased risk of permanent spinal cord ischemia, renal failure, visceral vessel ischemia, or aneurysm-related mortality that results from open thoracoabdominal aortic aneurysm repair. The high technical success rate, in native and previous repairs, supports the utility of this device as a bail-out technique for failed endovascular aneurysm repair or proximal extension of disease after previous aortic repair. However, experience is limited, and this approach requires further study before widespread adoption.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Procedimientos Endovasculares/instrumentación , Stents , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/mortalidad , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/mortalidad , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/mortalidad , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/mortalidad , Femenino , Humanos , Masculino , Complicaciones Posoperatorias/etiología , Estudios Prospectivos , Diseño de Prótesis , South Dakota , Factores de Tiempo , Resultado del Tratamiento
3.
J Vasc Surg ; 71(5): 1750-1757.e7, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31519510

RESUMEN

OBJECTIVE: Peripheral artery disease is the second most common cardiovascular disease. It can often occur in complex form when there is a presence of long, diffuse, and multiple lesions. Current treatments use either single long drug-coated balloons (DCBs) or multiple DCBs; however, treatment success is limited. The purpose of this study was to investigate the preclinical feasibility of our multiple-release Tailored Medical Devices DCB (MR-TMD-DCB) to treat multiple arterial segments using a single DCB. METHODS: The MR-TMD-DCBs were developed using a two-layer coating approach. The DCBs were developed in a certified Current Good Manufacturing Practices facility using presterilized materials and reagent and then characterized for coating morphology, thermal and chemical changes, and in vitro particulate shedding. The drug loss, tissue uptake, and undelivered drug amounts were analyzed using an in vitro peripheral artery flow model and explanted pig arteries. Then, an in vivo survival study was performed using a healthy porcine model to measure the short-term drug uptake (seven swine; 14 treatments at day 1) and retention (seven swine; 14 treatments at day 7) in two different arterial segments after treatment with a single MR-TMD-DCB. RESULTS: The coating on the MR-TMD-DCB was smooth and homogeneous with paclitaxel molecularly dispersed in its amorphous state. A negligible number of particulates were shed from the MR-TMD-DCB coating. A similar amount of drug was accurately delivered into two separate explanted arteries using a single MR-TMD-DCB during the in vitro flow model testing (707 ± 109 ng/mg in the first explanted artery and 783 ± 306 ng/mg in the second explanted artery). The MR-TMD-DCB treatment resulted in equivalent drug amounts in the two arterial segments at day 1 (63 ± 19 ng/mg in the first treatment site and 59 ±19 ng/mg in the second treatment site) and at day 7 (9 ± 6 ng/mg in the first treatment site and 10 ± 6 ng/mg in the second treatment site). In addition, the drug levels at each time point were in the clinically relevant range to prevent neointimal hyperplasia. CONCLUSIONS: The MR-TMD-DCBs provided equivalent and clinically relevant drug retention levels into two different arterial segments. Thus, MR-TMD-DCBs can be used to accurately deliver drug into multiple arterial segments with the use of a single DCB. The clinical outcomes of these findings need further investigation. Future long-term pharmacokinetics and safety studies will be performed to evaluate the safety and efficacy of the MR-TMD-DCB.


Asunto(s)
Angioplastia de Balón/instrumentación , Fármacos Cardiovasculares/administración & dosificación , Paclitaxel/administración & dosificación , Enfermedad Arterial Periférica/terapia , Animales , Fármacos Cardiovasculares/química , Materiales Biocompatibles Revestidos , Modelos Animales de Enfermedad , Paclitaxel/química , Material Particulado , Porcinos , Grado de Desobstrucción Vascular
4.
Mater Sci Eng C Mater Biol Appl ; 93: 61-69, 2018 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-30274093

RESUMEN

Construction of an artificial vascular graft is widely considered a promising strategy in vascular tissue engineering. However, limited sources of functional vascular smooth muscle cells (VSMCs) remain a major obstacle in vascular tissue engineering. In this study, we innovatively developed an approach to obtain functional VSMCs by onsite differentiating human bone marrow-derived mesenchymal stem cells (MSCs) directed by decellularized extracellular matrix (ECM) and fibroblasts. The resulting cells and ECM-cells constructs were characterized by real time RT-PCR, immunofluorescence staining, cell contractile functions, and migration capacity. Our results showed both ECM and fibroblasts induced MSCs differentiation toward VSMC-like cells with increased transcription of marker genes, upregulated expression of contractile apparatus proteins, and enhanced functional activity of VSMC phenotype. Interestingly, our findings revealed that native ECM and fibroblasts-coculture had a higher potential to promote MSCs differentiation into VSMCs than growth factors cocktail (GFC) supplemented culture, thereby providing a potential source of VSMCs for blood vessel constitution.


Asunto(s)
Prótesis Vascular , Diferenciación Celular , Matriz Extracelular/química , Fibroblastos/metabolismo , Células Madre Mesenquimatosas/metabolismo , Miocitos del Músculo Liso/metabolismo , Ingeniería de Tejidos , Técnicas de Cocultivo , Fibroblastos/citología , Humanos , Células Madre Mesenquimatosas/citología , Miocitos del Músculo Liso/citología
5.
J Vasc Surg ; 67(5): 1537-1545.e7, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-28843789

RESUMEN

OBJECTIVE: The purpose of this study was to investigate the newly developed drug-coated balloon (DCB) using polyethylene oxide (PEO) as a platform and to compare it directly with a commercially available DCB in a preclinical experimental setting. METHODS: The PEO balloon was characterized for coating morphology and degree of paclitaxel (PAT) crystallinity. PAT tissue levels were then measured up to 30 days in a healthy porcine model (10 swine, 20 vessels) after treatment with either a PEO balloon or a commercially available DCB. An in vitro bench-top model was used to compare the particulates released from the PEO balloon and commercially available DCB. RESULTS: The coating on the PEO balloon was smooth and homogeneous with PAT in its amorphous state. From the porcine survival study, the PAT tissue levels were comparable between PEO balloon and commercially available DCB after 7 days of treatment. Both the PEO balloon and the commercially available DCB retained therapeutic drug up to 30 days. During the simulated in vitro model, the PEO balloon shed significantly fewer particulates that were smaller than those of the commercially available DCB. Most important, the PEO balloon shed 25 times fewer large particulates than the commercially available DCB. CONCLUSIONS: The amorphous PAT in the PEO balloon provided comparable drug tissue retention levels to those of the commercially available DCB and fewer particulates. Thus prepared PEO balloon proved to be safe and effective in the preclinical experimental setting. The clinical outcomes of these findings need further investigation.


Asunto(s)
Angioplastia de Balón/instrumentación , Fármacos Cardiovasculares/administración & dosificación , Materiales Biocompatibles Revestidos , Portadores de Fármacos , Arteria Ilíaca/efectos de los fármacos , Paclitaxel/administración & dosificación , Polietilenglicoles/química , Dispositivos de Acceso Vascular , Animales , Fármacos Cardiovasculares/química , Fármacos Cardiovasculares/farmacocinética , Cristalización , Composición de Medicamentos , Liberación de Fármacos , Femenino , Arteria Ilíaca/metabolismo , Arteria Ilíaca/patología , Paclitaxel/química , Paclitaxel/farmacocinética , Tamaño de la Partícula , Conejos , Solubilidad , Propiedades de Superficie , Sus scrofa , Distribución Tisular
7.
S D Med ; 70(3): 109-117, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28813772

RESUMEN

OBJECTIVE: To evaluate the safety and efficacy of a one-time infusion of paclitaxel through an Atrium ClearWay balloon in infra inguinal de novo peripheral lesions. METHODS: This is a single-center prospective study looking at treatment of 50 limbs. Treatment includes standard infra inguinal endovascular revascularization followed by a pre-prescribed infusion of paclitaxel. Control is standard reintervention without subsequent paclitaxel infusion. Patients were followed at one, four, and 10 months with ankle-brachial index (ABI)s, arterial duplex of the treated limb, and Rutherford classification stage measured before and after procedures and at each follow-up. Freedom from binary restenosis was tracked with duplex ultrasound, and freedom from target lesion revascularization (TLR) was also tracked in the treatment group. Binary restenosis and TLR data was harvested from the patient record for the control group. RESULTS: Average ABI and Rutherford classification stage improved as expected. The treatment group had a freedom from TLR rate of 86 percent and a freedom from binary restenosis rate of 80 percent at 10 months. Average ABI improved from 0.65 at baseline to 0.94 at 10 months in the treatment group. The control group had a 72 percent freedom from TLR and a 58 percent freedom from binary restenosis at 10 months. Average ABI of the control group improved from 0.67 at baseline to 0.85 at 10 months in the control group. There were no amputations, open bypass revascularizations, or hypersensitivity reactions observed in the treatment group. CONCLUSIONS: Infusion of paclitaxel in de novo lesions appears to be a safe and efficacious treatment in the peripheral vasculature when compared to a historical control group. While it is early, it appears that the patients do receive some benefit from this one time infusion, and this approach should be studied further.


Asunto(s)
Angioplastia de Balón , Fármacos Cardiovasculares/administración & dosificación , Paclitaxel/administración & dosificación , Enfermedad Arterial Periférica/terapia , Anciano , Estudios de Casos y Controles , Humanos , Extremidad Inferior/irrigación sanguínea , Proyectos Piloto , Estudios Prospectivos
8.
J Biomed Mater Res A ; 105(9): 2441-2450, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28466979

RESUMEN

Polytetrafluoroethylene (PTFE) is one of the commonly used materials in making various cardiovascular implants. However, the success rates of these implants in several occasions are hindered by unwanted immune responses from immune cells, such as macrophages. In this study, we investigated the response of macrophages with different structures (flat, expanded, and electrospun) of PTFE having varied surface topographies: smooth planar surface (flat PTFE), node-fibrils (ePTFE), and randomly oriented microfibers (electrospun PTFE). The electrospun PTFE showed the least adhesion of macrophages. Also, the morphology of macrophages adhered on electrospun PTFE exhibited minimal activation. The macrophage pro-inflammatory cytokine secretions showed that the lowest level of TNF-α was produced on electrospun PTFE whereas IP-10 was produced in lowest levels on expanded PTFE (ePTFE). The production of IL-6 and MCP-1 cytokines was also dependent on the structure of PTFE that the macrophages interacted with, but in a time-dependent manner. Confocal microscopy images taken at 7, 14, and 21 days showed that the electrospun PTFE resulted in the lowest percentage of macrophage fusion, thus indicating the least possible chance of foreign body giant cell (FBGC) formation. Therefore, this study showed that electrospun PTFE with randomly oriented microfibers can provide reduced adhesion, activation, and FBGC formation of macrophages compared to the smooth and planar surface of flat PTFE and node-fibril structured surface of ePTFE. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2441-2450, 2017.


Asunto(s)
Células Gigantes de Cuerpo Extraño/citología , Activación de Macrófagos/efectos de los fármacos , Macrófagos/citología , Politetrafluoroetileno/química , Politetrafluoroetileno/farmacología , Animales , Materiales Biocompatibles/farmacología , Adhesión Celular/efectos de los fármacos , Recuento de Células , Citocinas/metabolismo , Células Gigantes de Cuerpo Extraño/efectos de los fármacos , Mediadores de Inflamación/metabolismo , Macrófagos/efectos de los fármacos , Ratones , Células RAW 264.7
9.
J Biomed Mater Res B Appl Biomater ; 105(2): 376-390, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-26513737

RESUMEN

Drug-infusion balloons are one of the currently used local drug delivery devices for preventing restenosis after endovascular treatments. An antiproliferative drug (paclitaxel, PAT) is infused through the balloon using a cremophor-based formulation to control restenosis. However, the major limitations of this approach are poor in vivo drug uptake and a limit in the amount of PAT delivered because of cremophor toxicity. In this study, we have investigated the use of different excipients for effectively infusing PAT out of the balloon for improved drug uptake in the tissue. The excipients include nanoparticle albumin-bound PAT (nab-PAT, a nanobiomaterial used in cancer therapy), urea (a hydrophilic agent used for faster drug transfer), iodixanol (a contrast agent used for coronary angiography), and cremophor-PAT (the most commonly used PAT formulation). An in vitro drug release, smooth muscle cell (SMC) response, endothelial cell (EC) response, and in vivo drug uptake were investigated for all the different excipients of PAT infused through the balloon. The nab-PAT was as effective as cremophor in infusing out of the balloon and inhibiting SMC growth. Also, nab-PAT showed a significantly greater amount of in vivo PAT uptake than that of cremophor-PAT. Urea and iodixanol were not effective in delivering a clinically relevant dose of PAT due to the poor solubility of PAT in these excipients. Urea eradicated all the SMCs and ECs, suggesting a toxic effect, which impedes its use in balloon-based therapy. Thus, this study demonstrated that nab-PAT is an effective formulation to locally deliver PAT through infusion balloons. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 376-390, 2017.


Asunto(s)
Catéteres , Sistemas de Liberación de Medicamentos/métodos , Células Endoteliales/metabolismo , Miocitos del Músculo Liso/metabolismo , Paclitaxel/farmacología , Células Endoteliales/citología , Humanos , Miocitos del Músculo Liso/citología , Porosidad
10.
J Vasc Surg ; 65(6): 1813-1819, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-27693030

RESUMEN

OBJECTIVE: This study proposes to establish a simulation-based technique for evaluating shear accumulation in stent grafts and to use the technique to assess the performance of a novel branched stent graft system. METHODS: Computational fluid dynamics models, with transient boundary conditions, particle injection, and rigid walls, simplifying assumptions were developed and used to evaluate the shear accumulation in various stent graft configurations with a healthy aorta as comparison. RESULTS: Shear streamlines are presented for the various configurations. Shear accumulation was also calculated for each configuration. The number of particles with shear accumulations >3.5 Pa-s for each configuration was compared with the shear accumulation values of commercially available mechanical aortic valves from the literature. CONCLUSIONS: The stent graft configuration with the diaphragm does have particles with shear accumulation >3.5 Pa-s. However, the percentage of particles with shear accumulation above 3.5 Pa-s is less than the two commercially available mechanical aortic valves, and more surprisingly, is smaller than in the healthy aorta.


Asunto(s)
Aorta Torácica/cirugía , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/instrumentación , Diseño de Prótesis , Stents , Tromboembolia/etiología , Aorta Torácica/fisiopatología , Velocidad del Flujo Sanguíneo , Simulación por Computador , Humanos , Hidrodinámica , Modelos Cardiovasculares , Flujo Pulsátil , Flujo Sanguíneo Regional , Medición de Riesgo , Factores de Riesgo , Estrés Mecánico , Tromboembolia/fisiopatología
11.
J Biomed Mater Res A ; 104(9): 2291-304, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27119260

RESUMEN

In this study, the effect of different structures (flat, expanded, and electrospun) of polytetrafluoroethylene (PTFE) on the interactions of endothelial cells (ECs), smooth muscle cells (SMCs), and platelets was investigated. In addition, the mechanisms that govern the interactions between ECs, SMCs, and platelets with different structures of PTFE were discussed. The surface characterizations showed that the different structures of PTFE have the same surface chemistry, similar surface wettability and zeta potential, but uniquely different surface topography. The viability, proliferation, morphology, and phenotype of ECs and SMCs interacted with different structures of PTFE were investigated. Expanded PTFE (ePTFE) provided a relatively better surface for the growth of ECs. In case of SMC interactions, although all the different structures of PTFE inhibited SMC growth, a maximum inhibitory effect was observed for ePTFE. In case of platelet interactions, the electrospun PTFE provided a better surface for preventing the adhesion and activation of platelets. Thus, this study demonstrated that the responses of ECs, SMCs, and platelets strongly dependent on the surface topography of the PTFE. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2291-2304, 2016.


Asunto(s)
Plaquetas/metabolismo , Células Endoteliales/metabolismo , Ensayo de Materiales , Miocitos del Músculo Liso/metabolismo , Adhesividad Plaquetaria , Politetrafluoroetileno/química , Plaquetas/citología , Línea Celular , Células Endoteliales/citología , Humanos , Miocitos del Músculo Liso/citología , Propiedades de Superficie
12.
Vascular ; 24(1): 103-5, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25972031

RESUMEN

Here we present three cases performed using a novel technique where aortic flow is compartmentalized proximal to the target vessels through a physician-modified endograft. The visceral segment is then further compartmentalized by the use of another physician modified endograft. By compartmentalizing the flow proximal to the visceral segment, both the true lumen and false lumen can be used as conduits for coextensive bridging stent grafts. Overall, patients have tolerated this procedure extremely well, and while further study and follow-up must be conducted, this procedure could offer a reasonable long-term solution to thoracoabdominal aortic aneurysms complicated by dissection.


Asunto(s)
Aneurisma de la Aorta Torácica/cirugía , Disección Aórtica/cirugía , Implantación de Prótesis Vascular/métodos , Procedimientos Endovasculares/métodos , Anciano , Disección Aórtica/diagnóstico , Disección Aórtica/fisiopatología , Aneurisma de la Aorta Torácica/diagnóstico , Aneurisma de la Aorta Torácica/fisiopatología , Prótesis Vascular , Implantación de Prótesis Vascular/instrumentación , Enfermedad Crónica , Procedimientos Endovasculares/instrumentación , Humanos , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Flujo Sanguíneo Regional , Resultado del Tratamiento
13.
Acta Biomater ; 29: 333-351, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26432441

RESUMEN

Drug-coated balloons (DCBs) are used to treat various cardiovascular diseases. Currently available DCBs carry drug on the balloon surface either solely or using different carriers. Several studies have shown that a significant amount of drug is lost in the blood stream during balloon tracking to deliver only a sub-therapeutic level of drug at the treatment site. This research is focused on developing paclitaxel (PAT) loaded polyethylene oxide (PEO) films (PAT-PEO) as a controlled drug delivery carrier for DCBs. An array of PAT-PEO films were developed in this study to provide tailored release of >90% of drug only at specific time intervals, which is the time frame required for carrying out balloon-based therapy. The characterizations of PAT-PEO films using SEM, FTIR, and DSC showed that the films developed were homogenous and the PAT was molecularly dispersed in the PEO matrix. Mechanical tests showed that most PAT-PEO films developed were flexible and ductile, with yield and tensile strengths not affected after PAT incorporation. The viability, proliferation, morphology, and phenotype of smooth muscle cells (SMCs) interacted with control-PEO and PAT-PEO films were investigated. All control-PEO and PAT-PEO films showed a significant inhibitory effect on the growth of SMCs, with the degree of inhibition strongly dependent on the w/v% of the polymer used. The PAT-PEO coating was produced on the balloons. The integrity of PAT-PEO coating was well maintained without any mechanical defects occurring during balloon inflation or deflation. The drug release studies showed that only 15% of the total PAT loaded was released from the balloons within the initial 1min (typical balloon tracking time), whereas 80% of the PAT was released between 1min and 4min (typical balloon treatment time). Thus, this study demonstrated the use of PEO as an alternate drug delivery system for the balloons. STATEMENT OF SIGNIFICANCE: Atherosclerosis is primarily responsible for cardiovascular diseases (CVDs) in millions of patients every year. Drug-coated balloons (DCBs) are commonly used to treat various CVDs. However, in several currently used DCBs, a significant amount of drug is lost in the blood stream during balloon tracking to deliver only a sub-therapeutic level of drug at the treatment site. In this study, paclitaxel containing polyethylene oxide (PEO) films were developed to provide unique advantages including drug release profiles specifically tailored for balloon-based therapy, homogeneous films with molecularly dispersed drug, flexible and ductile films, and exhibits significant inhibitory effect on smooth muscle cell growth. Thus, this study demonstrated the use of PEO as an alternate drug delivery platform for DCBs to improve its efficacy.


Asunto(s)
Angioplastia de Balón/métodos , Catéteres , Membranas Artificiales , Paclitaxel , Polietilenglicoles , Aorta/metabolismo , Aorta/patología , Células Cultivadas , Humanos , Músculo Liso/metabolismo , Músculo Liso/patología , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/patología , Paclitaxel/química , Paclitaxel/farmacocinética , Paclitaxel/farmacología , Polietilenglicoles/química , Polietilenglicoles/farmacocinética , Polietilenglicoles/farmacología
14.
J Biomed Mater Res B Appl Biomater ; 104(7): 1416-30, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-26227252

RESUMEN

Drug-coated balloons (DCBs) have now emerged as a promising approach to treat peripheral artery disease. However, a significant amount of drug from the balloon surface is lost during balloon tracking and results in delivering only a subtherapeutic dose of drug at the diseased site. Hence, in this study, the use of dextran sulfate (DS) polymer was investigated as a platform to control the drug release from balloons. An antiproliferative drug, paclitaxel (PAT), was incorporated into DS films (PAT-DS). The characterizations using SEM, FT-IR, and DSC showed that the films prepared were smooth and homogenous with PAT molecularly dispersed in the bulk of DS matrix in amorphous form. An investigation on the interaction of smooth muscle cells (SMCs) with control-DS and PAT-DS films showed that both films inhibited SMC growth, with a superior inhibitory effect observed for PAT-DS films. PAT-DS coatings were then produced on balloon catheters. The integrity of coatings was well-maintained when the balloons were either deflated or inflated. In this study, up to 2.2 µg/mm(2) of PAT was loaded on the balloons using the DS platform. Drug elution studies showed that only 10 to 20% of the total PAT loaded was released from the PAT-DS coated balloons during the typical time period of balloon tracking (1 min) and then ∼80% of the total PAT loaded was released during the typical time period of balloon inflation and treatment (from 1 min to 4 min). Thus, this study demonstrated the use of DS as a platform to control drug delivery from balloons. © 2015 The Authors Journal of Biomedical Materials Research Part B: Applied Biomaterials Published by Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1416-1430, 2016.


Asunto(s)
Angioplastia de Balón/instrumentación , Materiales Biocompatibles Revestidos , Sulfato de Dextran , Sistemas de Liberación de Medicamentos/métodos , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Paclitaxel , Células Cultivadas , Materiales Biocompatibles Revestidos/química , Sulfato de Dextran/química , Sulfato de Dextran/farmacología , Humanos , Ensayo de Materiales , Músculo Liso Vascular/citología , Miocitos del Músculo Liso/citología , Paclitaxel/química , Paclitaxel/farmacología , Enfermedad Arterial Periférica/metabolismo , Enfermedad Arterial Periférica/terapia
15.
J Vasc Surg ; 64(3): 788-96, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26209577

RESUMEN

OBJECTIVE: This study examined the flow behavior of four stent graft configurations for endovascular repair of complex aneurysms of the descending aorta. METHODS: Computational fluid dynamics models with transient boundary conditions and rigid wall simplifying assumptions were developed and used with four distinct geometries to compare various near-wall hemodynamic parameters. RESULTS: Graphic plots for time-averaged wall shear stress, oscillating shear index, and relative residence time were presented and compared among the four stent graft configurations of interest. CONCLUSIONS: Abrupt 90° and 180° changes in stent geometry (particularly in the side branches) cause a high momentum change and thus increased flow separation and mixing, which has significant implications in blood flow characteristics near the wall. By comparison, longer bridging stents provide more gradual changes in momentum, thus allowing blood flow to develop before reaching the target vessel.


Asunto(s)
Aorta Torácica/cirugía , Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Procedimientos Endovasculares/instrumentación , Hemodinámica , Stents , Aorta Torácica/fisiopatología , Aneurisma de la Aorta Torácica/fisiopatología , Velocidad del Flujo Sanguíneo , Simulación por Computador , Humanos , Hidrodinámica , Modelos Cardiovasculares , Diseño de Prótesis , Flujo Sanguíneo Regional , Estrés Mecánico , Factores de Tiempo , Grado de Desobstrucción Vascular
16.
Ann Vasc Surg ; 29(7): 1468-74, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26122416

RESUMEN

BACKGROUND: This article presents an endovascular approach to repair a unilateral or bilateral aortoiliac aneurysm with a bifurcated iliac limb that can maintain perfusion to the internal iliac artery (IIA) bilaterally through a brachial access. METHODS: A standard infrarenal aortic aneurysm repair is performed followed by iliac aneurysm exclusion. To obtain exclusion in the common iliac artery aneurysm, a bifurcated Endurant iliac limb is modified to compartmentalize iliac flow 2-3 cm above the internal iliac ostia. Then, a balloon-expandable covered stent graft is used to achieve sealing in the IIA and external iliac artery (EIA). The IIA is stented from the arm and the EIA is stented from the groin. RESULTS: There was no in-hospital or 30-day mortality. The procedural design was followed in each of the patients who received treatment. Technical success was 100%, short-term clinical success was 92%, and midterm clinical success was 83%. Average dosage of contrast medium was 116 mL (range, 55-193 mL), and average fluoroscopy time was 42.1 min (range, 20.8-91.6 min). Average length of hospital stay was 2.6 days (range, 1-9 days). There was 1 recorded endoleak. No reports of gluteal claudication, sexual dysfunction, or bowel or spinal claudication have been found. CONCLUSIONS: The technique described here does not require an up-and-over approach, allowing simplified bilateral repair. Although this is a promising technique, long-term durability needs to be evaluated in a controlled prospective study.


Asunto(s)
Angioplastia de Balón/instrumentación , Aneurisma de la Aorta/cirugía , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Aneurisma Ilíaco/cirugía , Stents , Anciano , Anciano de 80 o más Años , Angioplastia de Balón/efectos adversos , Aneurisma de la Aorta/diagnóstico , Aneurisma de la Aorta/fisiopatología , Aortografía , Implantación de Prótesis Vascular/efectos adversos , Medios de Contraste/administración & dosificación , Humanos , Aneurisma Ilíaco/diagnóstico , Aneurisma Ilíaco/fisiopatología , Tiempo de Internación , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Diseño de Prótesis , Flujo Sanguíneo Regional , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
17.
Vascular ; 23(3): 310-5, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25015113

RESUMEN

Patients suffering from aortic arch aneurysms continue to encounter few treatment options. Because of co-morbidities, most are deemed to not be open surgical candidates. The two cases presented here demonstrate a novel endovascular approach in the care of an arch aneurysm complicated by dissection. Even though final graft configurations differed slightly between the two cases, all three great vessels were successfully de-branched through the combination of standard endovascular aneurysm repair techniques and modifications to off-the-shelf devices. Aortic flow was compartmentalized in the ascending aorta at or near the level of the sinotubular junction. This was done with a physician-assembled endografts. One of these lumens was dedicated to the descending aorta, while the other was further divided into three channels used to stent the great vessels. Completion angiography demonstrated patency in the arch, great vessels, and descending aorta. No endoleaks have been reported. Although data is limited, this approach appears promising.


Asunto(s)
Aorta Torácica/cirugía , Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Procedimientos Endovasculares , Stents , Anciano , Aneurisma de la Aorta Torácica/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
18.
J Vasc Surg Venous Lymphat Disord ; 3(3): 251-7, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26992302

RESUMEN

OBJECTIVE: The objective of this study was to evaluate the safety and effectiveness of ultrasound-accelerated thrombolysis in acute pulmonary embolism. METHODS: A retrospective study of 45 patients was performed to evaluate treatment of acute pulmonary embolism at a single center from January 2011 to December 2013. All patients were diagnosed with computed tomography or ventilation-perfusion scan and had hemodynamic instability (systolic blood pressure <100 mm Hg) or right-sided heart strain evidenced by right ventricular dilation, septal deviation, or hypokinesis by echocardiography or computed tomography. EkoSonic catheters (EKOS Corporation, Bothell, Wash) were placed into the affected pulmonary arteries, and recombinant tissue plasminogen activator was infused through the catheters at 0.5 to 1.0 mg/h per catheter. RESULTS: Hypotension (systolic blood pressure <100 mm Hg) was present in 12 patients, with 100% resolution by treatment completion. Tachycardia (heart rate >100 beats/minute) was present in 26 patients and resolved in 92% by treatment completion; the average heart rate for all patients decreased from 109 to 77 beats/minute during the treatment period. Direct pulmonary artery pressure measurement showed average decrease of 21.5 mm Hg, representing a 40.2% reduction. Postprocedure echocardiography demonstrated complete resolution of cardiac dysfunction in 64%. Patients received a total dose of 30.5 mg (range, 14-66 mg) recombinant tissue plasminogen activator during an infusion time of 14.2 hours (range, 8-21 hours). There were no deaths through 90 days of follow-up and no major periprocedural bleeding events. CONCLUSIONS: This retrospective study demonstrates the safety and efficacy of current ultrasound-accelerated thrombolysis methods to treat acute pulmonary embolism.


Asunto(s)
Embolia Pulmonar/terapia , Terapia Trombolítica , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Fibrinolíticos , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Arteria Pulmonar , Embolia Pulmonar/diagnóstico , Estudios Retrospectivos , Activador de Tejido Plasminógeno , Resultado del Tratamiento
19.
J Vasc Surg ; 60(5): 1177-1184, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24997805

RESUMEN

OBJECTIVE: The objective of this study was to demonstrate a technique that uses physician-assembled endografts to make use of the benefits of parallel grafts while also providing for circumferential seal and fixation in repair of thoracoabdominal aneurysms in inoperable patients. METHODS: A single-center all-comers retrospective analysis of 14 patients was performed that looked at the early outcomes of patients treated for thoracoabdominal aneurysms. Three Crawford type II, four type III, four type IV, and three type V thoracoabdominal aneurysms were treated. Contrast material, fluoroscopy time, length of stay, clinical success, and technical success were measured. RESULTS: There was no in-hospital, 30-day, or 6-month mortality. We found two type III endoleaks in the early design. One required coil embolization. Average volume of contrast material and average fluoroscopy time were 76.9 mL and 119.1 minutes, respectively. Average length of stay was 10.5 days, and average procedure time was 251.2 minutes. Clinical success was observed in 78.6% of patients to date, and technical success was observed in 85.7% of patients. CONCLUSIONS: Short-term results show that this approach is safe. The device can be safely implanted, is off-the-shelf, and can treat each of the Crawford thoracoabdominal aneurysm types. Finally, the assembly of off-the-shelf components may shorten the regulatory path for this physician-assembled endograft.


Asunto(s)
Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Procedimientos Endovasculares/instrumentación , Diseño de Prótesis , Stents , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta Torácica/diagnóstico , Aortografía , Implantación de Prótesis Vascular/efectos adversos , Medios de Contraste , Embolización Terapéutica , Endofuga/etiología , Endofuga/terapia , Procedimientos Endovasculares/efectos adversos , Humanos , Tiempo de Internación , Persona de Mediana Edad , Tempo Operativo , Estudios Retrospectivos , South Dakota , Factores de Tiempo , Resultado del Tratamiento
20.
Ann Vasc Surg ; 28(4): 1031.e15-20, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24184461

RESUMEN

BACKGROUND: Arteriovenous malformations (AVMs) are difficult to treat and manage because of their high recurrence and complication rates. In particular, peripheral AVMs pose multiple clinical challenges because of their high flow rates and the frequent presence of multifocal nidi. METHODS: A 37-year-old man with a massive AVM involving the left common, deep, and superficial femoral arteries and veins is discussed herein. After initially being treated at another facility with coil embolization in 2005, he went untreated until he presented to us in April 2012 with swelling, tissue breakdown, leg ulcers, pain, and difficulty walking. When our extensive packed coil embolization proved ineffective, we knew that other standard treatments would be impractical, given the size of the AVM. Because the patient was in significant danger of bleeding, we treated him endovascularly with a system of modified stent grafts to exclude the arterial branches feeding multiple nidi. RESULTS: Postoperative computed tomography angiography scans revealed exclusion of the AVM and excellent flow to the deep and superficial femoral arteries. At 6 months postoperatively, the patient had no complications, and the leg continued to decompress. At 8 months postoperatively, we started additional treatment using percutaneous sclerotherapy to treat residual areas. CONCLUSION: A modular hybrid bifurcated stent graft system is a viable option to treat or manage complex peripheral arteriovenous malformations.


Asunto(s)
Malformaciones Arteriovenosas/cirugía , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Procedimientos Endovasculares/instrumentación , Arteria Femoral/cirugía , Vena Femoral/cirugía , Stents , Adulto , Malformaciones Arteriovenosas/diagnóstico , Malformaciones Arteriovenosas/fisiopatología , Embolización Terapéutica , Arteria Femoral/anomalías , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/fisiopatología , Vena Femoral/anomalías , Vena Femoral/diagnóstico por imagen , Vena Femoral/fisiopatología , Hemodinámica , Humanos , Masculino , Inhibidores de Agregación Plaquetaria/uso terapéutico , Diseño de Prótesis , Flujo Sanguíneo Regional , Escleroterapia , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
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