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OBJECTIVE: In 2019, the management of end-stage kidney disease (ESKD) shifted away from "Fistula First" (FF) to "ESKD Life-Plan: Patient Life-Plan First then Access Needs." Indeed, some patients exhibit such excessive comorbidity that even relatively minor vascular surgery may be complicated. The purpose of this study was to retrospectively assess complications and mortality (and delineate operative futility) in patients undergoing arteriovenous fistula (AVF) creation in the FF era. METHODS: Consecutive AVFs created in a single institution before 2021 were retrospectively reviewed. Operative futility was defined as never-accessed fistula, no initiation of dialysis, failure of access maturation (despite secondary intervention), hemodialysis access-induced distal ischemia requiring ligation, early loss of secondary patency, and/or patient mortality within the first 6 postoperative months. RESULTS: A total of 401 AVFs were created including radial-cephalic (44%), brachial-cephalic (41%), and brachial-basilic (15%) constructions. Patients exhibited a mean age of 69 ± 15 years; 63% were male, and most (74%) were already being hemodialyzed at the time of fistula creation. Forty-five patients (11%) suffered a cardiac event, and five patients died (1%) within 90 days of their access surgery. Perioperative cardiac events were significantly more common after age 80 (19% vs 8%; P = .004); age >80 years was an independent predictor of major 90-day complications (odds ratio [OR], 1.88; 95% confidence interval [CI], 1.04-3.39; P = .036) and the sole independent predictor of major morbidity defined as cardiopulmonary complications, stroke, or death within the first year (OR, 2.01; 95% CI, 1.24-3.25; P = .004). Operative futility was encountered in 52% of the cohort (n = 208 patients): 40% (n = 160) of primary AVFs failed to mature despite assistance, 19% (n = 77) had lost secondary patency by 6 months, 13% of patients (n = 53) were never started on dialysis after access creation, 4% (n = 16) were dead by 6 months, 2% of AVFs (n = 10) matured but were never accessed, and 2% (n = 9) required ligation for hemodialysis access-induced distal ischemia. Not surprisingly, the sole independent protector against operative futility was that catheter-based dialysis had been established prior to AVF creation (OR, 0.36; 95% CI, 0.22-0.59; P < .01). CONCLUSIONS: Approximately 50% of primary AVF operations performed in the aggressive FF era were deemed futile. Octogenarians were particularly prone to futility and complications during this era. A paradigm shift, from FF to an "ESKD Life-Plan" will, hopefully, more thoughtfully match vascular access strategies to individual patient needs.
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Fístula Arteriovenosa , Derivación Arteriovenosa Quirúrgica , Fallo Renal Crónico , Anciano de 80 o más Años , Humanos , Masculino , Persona de Mediana Edad , Anciano , Femenino , Derivación Arteriovenosa Quirúrgica/efectos adversos , Estudios Retrospectivos , Grado de Desobstrucción Vascular , Resultado del Tratamiento , Fallo Renal Crónico/etiología , Diálisis Renal/efectos adversos , Fístula Arteriovenosa/etiología , Isquemia/etiologíaRESUMEN
OBJECTIVE: Occlusive disease of the common femoral artery can generate profound lower extremity ischemia as the normal collateral pathways from the profunda to the superficial femoral artery cannot adequately develop. In patients with lifestyle-limiting claudication, isolated common femoral endarterectomy (CFE) is highly effective. Because CFE does not provide direct, in-line flow to the plantar arch, it has been felt to provide inadequate revascularization to patients with chronic limb-threatening ischemia (CLTI). The purpose of this retrospective clinical study was to report and assess the natural history of selected patients with CLTI treated with isolated CFE (without concomitant infrainguinal revascularization). METHODS: Consecutive CFEs performed in a large, urban hospital for CLTI between 2014 and 2021 were reviewed. Patient characteristics, limb, and anatomical stages using the Wound, Ischemia, foot Infection (WIfI) and Global Limb Anatomic Staging System were tabulated. Limb-specific and survival-related end points were analyzed. RESULTS: Fifty-eight patients presenting with CLTI underwent isolated CFE (mean age, 74 ± 10 years; 62% male, 90% current or prior smoker). Comorbidities included diabetes (52%), coronary artery disease (55%), congestive heart failure (22%), and end-stage renal failure on hemodialysis (5%). Patients presented with either rest pain (36%) or tissue loss (64%); the latter group exhibited advanced limb threat (68% in WIfI stage 3 or 4). The majority of patients had associated severe infrainguinal disease (50% Global Limb Anatomic Staging Systems 3). After a median follow-up of 17 months (range, 10-29 months), vascular reintervention was required in 7 patients (12%). One patient (2%) required major limb amputation after presentation in WIfI stage 4 (W3I3fI0). Indeed, WIfI stage 4 was a significant univariate predictor of the need for subsequent infrainguinal bypass (P = .034). CONCLUSIONS: Isolated CFE as primary therapy in highly selected patients with CLTI was safe and effective. Index limb stage is predictive of the need for associated infrainguinal revascularization in this complex population.
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OBJECTIVE: Common femoral endarterectomy (CFE) comprises the current standard-of-care for symptomatic common femoral artery occlusive disease. Although it provides effective inflow revascularization via a single incision, it remains an invasive procedure in an often-frail patient population. The purpose of this retrospective clinical study was to assess the morbidity and mortality of CFE in a contemporary cohort. METHODS: Consecutive CFEs performed at a large, urban hospital were reviewed. Six-month mortality, local complications (hematoma, lymphatic leak, pseudoaneurysm, wound infection, and/or dehiscence), and systemic complications were analyzed using univariate and multivariate analyses. RESULTS: A total of 129 isolated CFEs were performed over 7 years for claudication (36%), rest pain (16%), tissue loss (29%), or acute on chronic limb ischemia (21%). Mean age was 75 ± 9 years, and 68% of patients were male. Comorbidities were prevalent, including coronary artery disease (54%), diabetes (41%), chronic pulmonary disease (25%), and congestive heart failure (22%). The majority of CFEs were performed under general anesthesia (98%) with patch angioplasty using bovine pericardium (73% vs 27% Dacron). Twenty-two patients (17%) sustained local complications following the procedure; their occurrence was significantly associated with obesity (P = .002) but no technical or operative factors. Nineteen patients (15%) sustained serious systemic complications; their occurrence was significantly associated with chronic limb-threatening ischemia (P < .001), and a high American Society of Anesthesiologists (ASA) class (P = .002). By 6 months, 17 patients (13%) had died. Being on dialysis, presenting with chronic limb-threatening ischemia, and being in a high ASA class at the time of operation were all associated with 6-month mortality; a high ASA class at the time of operation was independently predictive of mortality (odds ratio, 3.08; 95% confidence interval, 1.03-9.24; P = .044). CONCLUSIONS: Although commonly performed, CFE is not a benign vascular procedure. Disease presentation, anesthetic risk, and expected longevity play an important role in clinical outcomes. Evolving endovascular approaches to the common femoral artery could serve to reduce morbidity and mortality in the future.
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Endarterectomía , Arteria Femoral , Humanos , Masculino , Femenino , Endarterectomía/efectos adversos , Endarterectomía/mortalidad , Anciano , Estudios Retrospectivos , Arteria Femoral/cirugía , Factores de Riesgo , Anciano de 80 o más Años , Resultado del Tratamiento , Factores de Tiempo , Comorbilidad , Complicaciones Posoperatorias/mortalidad , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/epidemiología , Claudicación Intermitente/cirugía , Claudicación Intermitente/mortalidad , Medición de Riesgo , Enfermedad Arterial Periférica/cirugía , Enfermedad Arterial Periférica/mortalidad , Isquemia/mortalidad , Isquemia/cirugía , Hospitales Urbanos/estadística & datos numéricos , Arteriopatías Oclusivas/cirugía , Arteriopatías Oclusivas/mortalidad , Persona de Mediana EdadRESUMEN
BACKGROUND: Chronic limb-threatening (CLTI) is associated with 25% limb loss and 25% mortality at 1-year. Its lethality increases to 45% in patients subjected to a major amputation. Percutaneous peripheral intervention (PPI) constitutes an attractive and less morbid treatment option for patients with CLTI. The purpose of this study was to assess amputation-free survival (AFS) in a contemporary cohort treated with endovascular recanalization and assess its predictors. METHODS: Patients with CLTI undergoing endovascular revascularization at a single regional hospital between 2015-2019 were reviewed. Baseline demographic characteristics, Wound, Ischemia, and foot Infection (WIfI) stage, technical details, and clinical outcomes were tabulated. The primary endpoint was AFS; a P-value < 0.05 was used for univariate screening and inclusion in a multivariable model. RESULTS: A total of 137 limbs in 111 patients were studied. Comorbidities were prevalent and included diabetes (65%), congestive heart failure (21%), and dialysis dependence (18%). The majority of revascularized limbs presented with advanced wounds (66% WIfI stages 3-4; 47% Rutherford category 6). Presenting WIfI stages were similar across races (P = 0.26). Peripheral interventions most commonly targeted femoropopliteal disease (69%), although 26% were multilevel. Percutaneous atherectomy, stenting, and paclitaxel-coated or eluting devices were utilized in 68%, 28%, and 15% of cases, respectively. After a median follow-up of 16 months (interquartile range IQR = 4-29 months), significant independent predictors of reduced AFS included nonWhite race (HR = 2.96 [1.42-6.17]; P = 0.004) and WIfI stage 4 wounds (HR = 2.23 [1.10-4.52]; P = 0.026). At one year following successful revascularization, only 59% ± 1% of patients were alive with their limb intact. CONCLUSIONS: Despite considerable and consistent advances in urban health care delivery and the techniques of PPI, CLTI remains a morbid and deadly disease. Even in the endovascular era, nearly half of all patients presenting with CLTI will lose their limb and/or life within the first year. Unfortunately, late-stage presentation continues to be commonplace. Although endovascular intervention can reliably restore patency to affected arteries, this appears insufficient to restore most patients to health.
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Procedimientos Endovasculares , Enfermedad Arterial Periférica , Humanos , Recuperación del Miembro , Enfermedad Arterial Periférica/diagnóstico por imagen , Enfermedad Arterial Periférica/terapia , Isquemia Crónica que Amenaza las Extremidades , Procedimientos Endovasculares/efectos adversos , Resultado del Tratamiento , Factores de Riesgo , Factores de Tiempo , Isquemia/diagnóstico por imagen , Isquemia/cirugía , Enfermedad Crónica , Estudios RetrospectivosRESUMEN
BACKGROUND: Autogenous arteriovenous fistula creation is the preferred route for vascular access for hemodialysis. Although preoperative venous mapping ultrasonography has been advocated as an operative planning adjunct and recently incorporated into the Society for Vascular Surgery clinical guidelines, controversy remains regarding its usefulness for predicting access success. The purpose of the present retrospective clinical study was to test the hypothesis that vein size measured on routine preoperative venous mapping is a poor predictor of primary fistula maturation. METHODS: Consecutive upper extremity autogenous arteriovenous fistulas created by three dedicated vascular surgeons were retrospectively reviewed. The demographic characteristics, preoperative venous mapping, functional maturation, and patency were analyzed. The clinically relevant variables were tested for predictive significance using a logistic regression model. RESULTS: A total of 199 upper extremity autogenous arteriovenous fistulas had been created during a 5-year period. Patients were aged 70 ± 16 years (range, 20-96 years), and 62% were men. Most had already been undergoing dialysis before fistula creation (83%), usually via a tunneled central venous catheter (62%). Radial-cephalic, brachial-cephalic, and brachial-basilic arteriovenous fistulas had been created in 82 patients (41%), 76 patients (38%), and 10 patients (5%), respectively. Fistula maturation, defined as a palpable thrill and/or successful cannulation of the fistula with the ability to deliver a flow rate of 400 mL/min, was achieved in 67% of the patients. A higher body mass index was associated with nonmaturation on both univariate and multivariate analyses (success, 28.6 ± 7.7 kg/m2; vs failed, 31.6 ± 9.4 kg/m2; P = .029; odds ratio [OR], 1.06; 95% confidence interval [CI], 1.02-1.10; P < .01). On univariate analysis, the maximum target vein diameter assessed by preoperative venous mapping was slightly larger in the group achieving successful maturation (2.9 ± 1.1 mm vs 2.6 ± 0.9 mm; P = .014). However, neither the maximum target vein diameter nor a target vein size >3 mm was significantly predictive of maturation on multivariate analysis (maximum vein diameter: OR, 0.65; 95% CI, 0.35-1.22; P = .176; vein size >3 mm: OR, 0.91; 95% CI, 0.32-2.60; P = .857). After a median follow-up of 15 months (interquartile range, 26 months), the primary functional patency, primary-assisted patency, and secondary patency rates were 39.1% ± 0.6%, 94.5% ± 0.6%, and 97.9% ± 0.5%. No association of vein diameter with long-term patency was found. CONCLUSIONS: Despite the national fistula-first initiatives, most patients still undergo access via catheter at the initiation of hemodialysis. The use of routine preoperative venous mapping does not predict successful primary maturation. Also, no clinically useful predictor of fistula maturation was identified in the present study.
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Derivación Arteriovenosa Quirúrgica , Ultrasonografía , Extremidad Superior/irrigación sanguínea , Grado de Desobstrucción Vascular , Venas/diagnóstico por imagen , Venas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Derivación Arteriovenosa Quirúrgica/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Diálisis Renal , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: Percutaneous peripheral intervention (PPI) is often the first mode of therapy for patients with symptomatic arterial occlusive disease. Technical success generally remains high although "failure-to-cross" still complicates 5-20% of cases. Extended efforts to cross long, occlusive lesions can utilize significant hospital and practitioner resources. The hospital is typically reimbursed for this effort as facility fees are charged by the hour and materials are charged per use. However, given the lack of a CPT® code for "failure-to-cross," practitioners are rarely appropriately compensated. The purpose of this study is to analyze the predictors, technical details, outcomes, and costs of "failure-to-cross" during PPI. METHODS: All PPI procedures over a 2-year period at a single institution were retrospectively reviewed. Clinical characteristics, results, costs, and reimbursements obtained from hospital cost accounting were compared among successful therapeutic interventions, crossing failures, and diagnostic angiograms without attempted intervention. RESULTS: A total of 146 consecutive PPIs were identified; the rate of "failure-to-cross" was 11.6% (17 patients). The majority of patients with "failure-to-cross" were male (82%) with single-vessel runoff (53%). Compared to successful interventions, the incidences of chronic limb-threatening ischemia (82% vs. 70%, P = 0.34) and infrapopliteal occlusive disease were similar (47% vs. 31%, P = 0.20). "Failure-to-cross" procedures were just as long as successful procedures; there were no significant differences in fluoroscopy time (27 ± 10 vs. 24 ± 14 min, P = 0.52), in-room time (106 ± 98 vs. 103 ± 44 min, P = 0.84), or contrast dye volume utilization (73 ± 37 vs. 96 ± 54 mL, P = 0.12). As expected, "failure-to-cross" procedures incurred far higher hospital charges and costs compared to noninterventional diagnostic angiograms (charges $13,311 ± 6,067 vs. $7,690 ± 1,942, P < 0.01; costs $5,289 ± 2,099 vs. $2,826 ± 1,198, P < 0.01). Despite the additional time and effort spent attempting to cross difficult lesions, the operators were reimbursed at the same low rate as a purely diagnostic procedure (average fee charge $7,360; average reimbursement $992). After 1 year, the 17 patients in whom lesions could not be crossed were treated with advanced interventional procedures with success (n = 2), surgical bypass grafting (n = 5), extremity amputation (n = 4), or no additional intervention in their salvaged limb (n = 6). CONCLUSIONS: Patients whose lesions cannot be crossed during PPI fare worse than patients undergoing successful interventions. Hospital costs and charges appropriately reflect the high technical difficulty and resource utilization of extended attempts at endovascular therapy. For practitioners, crossing lesions during PPI is truly a "pay-for-performance" procedure in that only successful procedures are reasonably reimbursed.
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Procedimientos Endovasculares/economía , Planes de Aranceles por Servicios/economía , Costos de la Atención en Salud , Isquemia/economía , Isquemia/terapia , Enfermedad Arterial Periférica/economía , Enfermedad Arterial Periférica/terapia , Reembolso de Incentivo/economía , Anciano , Anciano de 80 o más Años , Enfermedad Crónica , Current Procedural Terminology , Procedimientos Endovasculares/efectos adversos , Femenino , Precios de Hospital , Costos de Hospital , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Resultado del TratamientoRESUMEN
BACKGROUND: Designing peripheral arterial stents has proved challenging, as implanted devices will repetitively and unpredictably deform and fatigue during movement. Preclinical testing is often inadequate, given the lack of relevant animal models. The purpose of this study was to test the hypothesis that deformation of the human peripheral vasculature could be qualitatively and quantitatively modeled using an experimental animal. METHODS: Anteroposterior contrast angiography was performed in domestic Landrace-Yorkshire farm pigs. Images were obtained with the hind limbs naturally extended then repeated, (1) flexed approximately 90° at the hip and knee, (2) overflexed in a nonphysiological fashion. Quantitative vascular angiographic analysis was utilized to measure arterial diameter, length, and deformation. Percent axial arterial compression and bending were assessed. RESULTS: Eight iliofemoral arteries in four animals were imaged. Mean luminal diameters of the iliac and femoral segments in the neutral position were 5.4 ± 0.5 mm and 4.6 ± 0.5 mm. Hind limb physiologic flexion induced profound arterial compression, 17 ± 8% and 29 ± 6% and bending, 36°±10° and 76° ± 13° within the iliac and femoral segments, respectively. With extreme flexion, the femoral artery could be reliably bent >90°. The observed findings exceeded the deformation observed historically within the human superficial femoral (â¼5% compression and 10° bending) and popliteal artery (â¼10% compression and 70° bending). CONCLUSIONS: Significant nonradial deformation of the porcine iliofemoral arteries was observed during manual hind limb flexion and exceeded that typically observed in humans. This model constitutes a "worst case" scenario for testing deformation and fatigue of intravascular devices indicated for the human peripheral vasculature.
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Arteria Femoral/fisiología , Ensayo de Materiales/métodos , Arteria Poplítea/fisiología , Diseño de Prótesis , Falla de Prótesis , Angiografía , Animales , Fenómenos Biomecánicos , Medios de Contraste/administración & dosificación , Procedimientos Endovasculares/instrumentación , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/cirugía , Miembro Posterior/irrigación sanguínea , Miembro Posterior/fisiología , Humanos , Masculino , Modelos Animales , Arteria Poplítea/diagnóstico por imagen , Arteria Poplítea/cirugía , Rango del Movimiento Articular/fisiología , Stents , Estrés Mecánico , Sus scrofa , Enfermedades Vasculares/cirugíaRESUMEN
BACKGROUND: Drug-coated balloons are increasingly used for peripheral vascular disease, and, yet, mechanisms of tissue uptake and retention remain poorly characterized. Most systems to date have used paclitaxel, touting its propensity to associate with various excipients that can optimize its transfer and retention. We examined zotarolimus pharmacokinetics. METHODS AND RESULTS: Animal studies, bench-top experiments, and computational modeling were integrated to quantify arterial distribution after zotarolimus-coated balloon use. Drug diffusivity and binding parameters for use in computational modeling were estimated from the kinetics of zotarolimus uptake into excised porcine femoral artery specimens immersed in radiolabeled drug solutions. Like paclitaxel, zotarolimus exhibited high partitioning into the arterial wall. Exposure of intimal tissue to drug revealed differential distribution patterns, with zotarolimus concentration decreasing with transmural depth as opposed to the multiple peaks displayed by paclitaxel. Drug release kinetics was measured by inflating zotarolimus-coated balloons in whole blood. In vivo drug uptake in swine arteries increased with inflation time but not with balloon size. Simulations coupling transmural diffusion and reversible binding to tissue proteins predicted arterial distribution that correlated with in vivo uptake. Diffusion governed drug distribution soon after balloon expansion, but binding determined drug retention. CONCLUSIONS: A large bolus of zotarolimus releases during balloon inflation, some of which pervades the tissue, and a fraction of the remaining drug adheres to the tissue-lumen interface. As a result, the duration of delivery modulates tissue uptake where diffusion and reversible binding to tissue proteins determine drug transport and retention, respectively.
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Angioplastia de Balón/métodos , Sirolimus/análogos & derivados , Animales , Sistemas de Liberación de Medicamentos/métodos , Femenino , Arteria Femoral/efectos de los fármacos , Arteria Femoral/metabolismo , Masculino , Técnicas de Cultivo de Órganos , Paclitaxel/administración & dosificación , Paclitaxel/farmacocinética , Sirolimus/administración & dosificación , Sirolimus/farmacocinética , Porcinos , Distribución Tisular/efectos de los fármacos , Distribución Tisular/fisiologíaRESUMEN
BACKGROUND: The ZOMAXX I trial tested the noninferiority of a zotarolimus-eluting coronary stent (ZoMaxx(™) ) when compared with a paclitaxel-eluting coronary stent (Taxus(™) Express(2™) ) in a randomized trial of percutaneous intervention for de novo coronary artery stenosis. Angiographic analysis at the primary endpoint of 9 months has been reported previously. The purpose of this follow-on analysis was to describe the clinical results of the ZoMaxx and Taxus cohorts of the ZOMAXX I trial after 5 years. METHODS AND RESULTS: In the ZOMAXX I trial, 199 patients received a ZoMaxx stent and 197 patients received a Taxus stent at 29 investigative sites in Europe, Australia, and New Zealand. The two groups were generally well matched with respect to both clinical and lesional characteristics, including the incidence of diabetes (ZoMaxx 22% vs. Taxus 26%; P = 0.29), reference vessel diameter (ZoMaxx 2.79 ± 0.43 mm vs. Taxus 2.81 ± 0.46 mm; P = 0.65), and lesion length (ZoMaxx 14.9 ± 5.7 mm vs. Taxus 14.6 ± 5.5; P = 0.61). Through 5 years of follow-up, a total of 21 patients had died, six patients had withdrawn, nine had been lost to follow-up, and 13 missed their 5-year visit, leaving a total of 347 patients for analysis (169 ZoMaxx and 178 Taxus). At the 5-year time point, there were no significant differences in any clinical metric including ischemia-driven target lesion revascularization (TLR; ZoMaxx 10.6% vs. Taxus 7.1%; P = 0.29), Q-wave myocardial infarction (ZoMaxx 1.5% vs. Taxus 1.0%; P = 0.99), definite/probable stent thrombosis (ZoMaxx 1.5% vs. Taxus 3.0%; P = 0.34), and cardiac death (ZoMaxx 3.0% vs. Taxus 1.0%; P = 0.28). CONCLUSIONS: After 5 years, the differences in clinical outcome between patients treated with ZoMaxx vs. Taxus stents did not reach statistical significance. However, the nominally higher rate of ischemia-driven TLR (10.6 vs. 7.1%) and the previously reported higher rate of restenosis after 9 months suggest that the ZoMaxx stent afforded less neointimal inhibition when compared with Taxus. © 2013 Wiley Periodicals, Inc.
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Fármacos Cardiovasculares/administración & dosificación , Estenosis Coronaria/terapia , Stents Liberadores de Fármacos , Paclitaxel/administración & dosificación , Intervención Coronaria Percutánea/instrumentación , Sirolimus/análogos & derivados , Anciano , Australia , Angiografía Coronaria , Reestenosis Coronaria/etiología , Estenosis Coronaria/diagnóstico por imagen , Estenosis Coronaria/mortalidad , Trombosis Coronaria/etiología , Europa (Continente) , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/etiología , Neointima , Nueva Zelanda , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/mortalidad , Diseño de Prótesis , Factores de Riesgo , Índice de Severidad de la Enfermedad , Sirolimus/administración & dosificación , Factores de Tiempo , Resultado del TratamientoRESUMEN
Objective: Recanalization with balloon angioplasty and/or self-expanding stents (SES) has become the endovascular treatment of choice for symptomatic femoropopliteal occlusive disease. These strategies generate suboptimal clinical results, however, because they fail to expand the artery fully and ineffectively prevent recoil, neointimal hyperplasia, and restenosis. Balloon-expandable stents, given their greater radial force and rigid structure, represent a more effective treatment strategy, but only short lengths can be implanted safely in arteries that deform and bend with skeletal motion. The purpose of this preclinical experiment was to test the hypothesis that simultaneous implantation of a series of short, resorbable, balloon-expandable, paclitaxel-eluting scaffolds would prevent neointimal hyperplasia and stenosis compared with SES in an animal model of percutaneous femoropopliteal intervention. Methods: We extruded 6 × 60 mm Efemoral Vascular Scaffold Systems (EVSS) from copolymers of poly-L-lactic acid, coated with paclitaxel 3 µg/mm2, crimped onto a single delivery balloon, and implanted percutaneously into the iliofemoral arteries of eight Yucatan mini-swine. We implanted 7- to 8-mm × 60 mm SES into the contralateral experimental arteries. The animals were serially imaged with contrast angiography and optical coherence tomography after 30, 90, 180, 365, and 730 days. The primary end point of this study was neointimal morphometry over time. Secondary end points included acute deformation and angiographic and optical coherence tomography-derived measurements of chronic vascular response. Results: Over the 2-year study period, one SES was found to be completely occluded at 90 days; all EVSS were widely patent at all time points. Arteries treated with SES exhibited profound neointimal hyperplasia with in-stent stenosis. In contrast, arteries treated with EVSS exhibited only modest vascular responses and minimal stenosis. After 2 years, the mean neointimal thickness (0.45 ± 0.12 vs 1.31 ± 0.91 mm; P < .05) and area (8.41 ± 3.35 vs 21.86 ± 7.37 mm2; P < .05) were significantly decreased after EVSS implantation. By 2 years, all scaffolds in all EVSS-treated arteries had resorbed fully. Conclusions: In this preclinical animal model of peripheral endovascular intervention, the EVSS decreased neointimal hyperplasia and stenosis significantly compared with SES, then dissolved completely between the first and second years after implantation.
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INTRODUCTION: A novel self-expanding, drug-eluting stent (DES) was designed to slowly release everolimus in order to prevent restenosis after percutaneous peripheral intervention. The purpose of this experimental animal study was to test the hypothesis that long-term local, stent-mediated delivery of everolimus would reduce neointimal hyperplasia in porcine iliac arteries. METHODS: The iliac arteries of 24 Yucatan mini-swine were percutaneously treated with overlapping 8- × 28-mm self-expanding nitinol stents loaded with everolimus (225 µg/cm2 stent surface area) formulated in a poly(ethylene-co-vinyl alcohol) copolymer intended to deliver the drug in a sustained fashion over about 6 months (DES). Bare nitinol self-expanding stents (bare metal stent [BMS]) were implanted in an identical fashion on the contralateral side to serve as controls. After 3, 6, or 12 months, the animals were sacrificed and the stented arteries perfusion-fixed for histomorphometric analysis. RESULTS: The chronic presence of everolimus in arterial tissue reduced stent-induced inflammation after 3 months (inflammation score: BMS 2.29±0.44 vs DES 0.17±0.17; P=.001) and 6 months (BMS 2.06±0.43 vs DES 0.50±0.5; P=.007), although some late inflammation was observed after drug exhaustion (BMS 1.00±0.25 vs DES 2.56±0.62 after 12 months; P=not significant [NS]). Treatment with locally delivered everolimus significantly reduced neointimal hyperplasia after 3 months (neointimal thickness: BMS 0.79±0.20 vs DES 0.37±0.04 mm; P=.03) and 6 months (BMS 0.73±0.14 vs DES 0.41±0.08 mm; P=.05), although the effect had dissipated after 12 months (BMS 0.68±0.11 vs DES 0.67±0.11 mm; P=NS). Remarkably, stent-induced neoatherosclerosis, characterized by the histologic presence of foamy macrophages and cholesterol clefts, was significantly attenuated by treatment with everolimus (atherogenic change scores at 3 months: BMS 0.56±0.15 vs DES 0.04±0.04; P=.003; 6 months: BMS 0.84±0.23 vs DES 0.00±0.00; P=.004; and 12 months: BMS 0.09±0.10 vs DES 0.19±0.19; P=NS). CONCLUSIONS: In this experimental animal model, local arterial stent-mediated delivery of everolimus inhibited the formation of neointimal hyperplasia and neoatherosclerosis during the first 6 months. The effect was transient, however, as arterial morphology and histology appeared similar to control stented arteries after 12 months.
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Aterosclerosis/terapia , Stents Liberadores de Fármacos , Procedimientos Endovasculares , Oclusión de Injerto Vascular/prevención & control , Inmunosupresores/administración & dosificación , Sirolimus/análogos & derivados , Animales , Aterosclerosis/etiología , Aterosclerosis/patología , Modelos Animales de Enfermedad , Procedimientos Endovasculares/efectos adversos , Everolimus , Oclusión de Injerto Vascular/etiología , Oclusión de Injerto Vascular/patología , Hiperplasia/etiología , Hiperplasia/patología , Hiperplasia/prevención & control , Arteria Ilíaca/patología , Arteria Ilíaca/cirugía , Neointima/etiología , Neointima/patología , Neointima/prevención & control , Sirolimus/administración & dosificación , Porcinos , Porcinos EnanosRESUMEN
BACKGROUND: A novel self-expanding drug-eluting stent was designed to release everolimus 225 µg/cm(2) to prevent restenosis following peripheral arterial intervention. The purpose of this study was to measure the pharmacokinetic profile of everolimus following stent implantation. METHODS: One hundred four patients with symptomatic peripheral arterial disease underwent implantation of everolimus-eluting stents in the femoropopliteal arteries. In a prespecified subset of 26 patients, blood samples for assay of everolimus content were collected prior to stent implantation, at 1, 4, and 8 hours postprocedure, prior to discharge, and at 1 month postprocedure. RESULTS: A total of 39 stents, ranging from 28 mm to 100 mm in length, were implanted in 26 patients, resulting in a total delivered everolimus dose range of 3.0 to 7.6 mg. Following the procedure, the maximum observed everolimus blood concentrations (C(max)) varied from 1.83 ± 0.05 ng/mL after implantation of a single 80-mm stent to 4.66 ± 1.78 ng/mL after implantation of two 100-mm stents. The mean time to peak concentration (T(max)) varied from 6.8 hours to 35 hours. The pharmacokinetics of everolimus were dose-proportional in that dose-normalized C(max) and area under the curve values were constant over the studied dose range. CONCLUSIONS: After implantation of everolimus-eluting self-expanding stents in the femoropopliteal arteries, systemic blood concentrations of everolimus are predictable and considerably lower than blood concentrations observed following safe oral administration of everolimus.
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Fármacos Cardiovasculares/farmacocinética , Stents Liberadores de Fármacos , Procedimientos Endovasculares/instrumentación , Arteria Femoral , Enfermedad Arterial Periférica/terapia , Arteria Poplítea , Sirolimus/análogos & derivados , Anciano , Fármacos Cardiovasculares/administración & dosificación , Fármacos Cardiovasculares/sangre , Constricción Patológica , Europa (Continente) , Everolimus , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Diseño de Prótesis , Recurrencia , Sirolimus/administración & dosificación , Sirolimus/sangre , Sirolimus/farmacocinética , Resultado del TratamientoRESUMEN
OBJECTIVE: Critical limb ischemia, the most severe form of peripheral arterial disease, results in extremity amputation if left untreated. Endovascular recanalization of stenotic or occluded infrapopliteal arteries has recently emerged as an effective form of therapy, although the duration of patency is typically limited by restenosis. Recently, it has been suggested that drug-eluting stents originally developed for the coronary arteries might also be effective in preventing restenosis in the infrapopliteal arteries. This prospective, randomized, controlled clinical trial tested the hypothesis that treatment of infrapopliteal arterial occlusive lesions with an everolimus-eluting stent (Xience V) would provide superior patency to treatment with a bare-metal stent (Multi-Link Vision). METHODS: A sample size of 140 patients was planned to be enrolled at five European investigative sites. The primary end point was arterial patency at 12 months, defined as the absence of ≥50% restenosis based on quantitative analysis of contrast angiography. RESULTS: Between March of 2008 and September of 2009, 74 patients were treated with Xience V and 66 patients were treated with Vision. After 12 months, the primary patency rate after treatment with Xience V was 85% compared with 54% after treatment with Vision (P = .0001). Treatment with Xience V significantly reduced mean in-stent diameter stenosis (21% ± 21% vs 47% ± 27%; P < .0001) and mean in-stent late lumen loss (0.78 ± 0.63 vs 1.41 ± 0.89 mm; P = .001). There were no differences in the percentage of patients receiving a designation of Rutherford class 0 or 1 at the 12-month follow-up visit (56% for Vision, vs 60% for Xience V; P = .68). Major extremity amputations were rare in both groups (two for Vision and one for Xience V). The use of the Xience V stent significantly reduced the need for repeat intervention: freedom from target lesion revascularization was 91% for Xience V vs 66% for Vision (P = .001). CONCLUSIONS: Treatment of the infrapopliteal occlusive lesions of critical limb ischemia with everolimus-eluting stents reduces restenosis and the need for reintervention compared with bare metal stents.
Asunto(s)
Angioplastia/instrumentación , Arteriopatías Oclusivas/terapia , Fármacos Cardiovasculares/administración & dosificación , Stents Liberadores de Fármacos , Isquemia/terapia , Metales , Arteria Poplítea , Sirolimus/análogos & derivados , Stents , Anciano , Anciano de 80 o más Años , Amputación Quirúrgica , Angioplastia/efectos adversos , Arteriopatías Oclusivas/complicaciones , Arteriopatías Oclusivas/diagnóstico por imagen , Arteriopatías Oclusivas/fisiopatología , Constricción Patológica , Enfermedad Crítica , Europa (Continente) , Everolimus , Femenino , Humanos , Isquemia/diagnóstico por imagen , Isquemia/etiología , Isquemia/fisiopatología , Estimación de Kaplan-Meier , Recuperación del Miembro , Masculino , Persona de Mediana Edad , Arteria Poplítea/diagnóstico por imagen , Arteria Poplítea/fisiopatología , Estudios Prospectivos , Diseño de Prótesis , Radiografía , Recurrencia , Medición de Riesgo , Factores de Riesgo , Sirolimus/administración & dosificación , Factores de Tiempo , Resultado del Tratamiento , Grado de Desobstrucción VascularRESUMEN
Retroperitoneal fibrosis (RPF) is an uncommon fibrotic disorder that can cause pain, ureteral obstruction, deep venous thrombosis, hydrocele, and, rarely, aortic occlusion. Herein is described a 65-year-old man with aortic occlusion from idiopathic RPF who was treated with axillobifemoral bypass grafting, which failed in the intermediate term. On representation with critical claudication, he underwent thoracobifemoral bypass grafting via a lateral retroperitoneal tunnel created through a midline, infraumbilical counterincision. He was discharged home on postoperative day 5. This illustrates the successful use of thoracic aortic inflow to treat the aortoiliac occlusive complication of RPF.
RESUMEN
Understanding and recognizing anatomic anomalies of the aortic arch is important when planning extra-anatomic debranching before thoracic endovascular aortic repair. A rare anomaly is the left vertebral artery aberrantly arising from the aortic arch; found in â¼5% of adults. When present, the artery courses through the carotid sheath at a variable length before entering the third or fourth cervical transverse foramen. In the present report, we have described the case of a 49-year-old man with a symptomatic, enlarging type B aortic dissection with an aberrant left vertebral artery and the novel methods used to surgically correct his pathology.
RESUMEN
Symptomatic femoropopliteal occlusive disease has been increasingly treated using endovascular methods. However, restenosis, especially after implantation of permanent metallic stents, has remained common. To date, resorbable scaffolds have failed to achieve sufficient radial strength to enable the successful treatment of long, mobile, peripheral arteries. In the present nonsurvival, large animal experiment, a novel device consisting of multiple, short, serial, balloon-expandable, bioresorbable scaffolds was deployed in arteries subjected to supraphysiologic deformation. Compared with native vessels, the scaffolded arteries continued to bend (113° ± 19° vs 110° ± 20°; P = .10) and shorten (15% ± 15% vs 20% ± 14%; P = .16), unencumbered by the placement of the investigational device. The mean luminal diameter of the scaffolded arteries was preserved without kinks or occlusions in exaggerated flexion (4.7 ± 0.7 vs 4.7 ± 0.5 mm in extension vs flexion; P = .80). Arterial deformation was borne by shortening of the interscaffold spaces (2.2 ± 0.8 mm vs 1.9 ± 0.7 mm in extension vs flexion; P < .01) and the scaffolds themselves (10.7 ± 1.4 mm vs 9.9 ± 1.1 mm in extension vs flexion; P < .01). The results from the present study challenge the perceived limitations of balloon-expandable devices implanted in peripheral mobile arteries. We have presented a bioresorbable scaffold that combines sufficient radial strength to preserve the mean luminal diameter with movement and the flexibility to accommodate femoropopliteal deformation.