927 resultados para Endovascular Presence


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OBJECTIVE: Intensive image surveillance after endovascular aneurysm repair is generally recommended due to continued risk of complications. However, patients at lower risk may not benefit from this strategy. We evaluated the predictive value of the first postoperative computed tomography angiography (CTA) characteristics for aneurysm-related adverse events as a means of patient selection for risk-adapted surveillance. METHODS: All patients treated with the Low-Permeability Excluder Endoprosthesis (W. L. Gore & Assoc, Flagstaff, Ariz) at a tertiary institution from 2004 to 2011 were included. First postoperative CTAs were analyzed for the presence of endoleaks, endograft kinking, distance from the lowermost renal artery to the start of the endograft, and for proximal and distal sealing length using center lumen line reconstructions. The primary end point was freedom from aneurysm-related adverse events. Multivariable Cox regression was used to test postoperative CTA characteristics as independent risk factors, which were subsequently used as selection criteria for low-risk and high-risk groups. Estimates for freedom from adverse events were obtained using Kaplan-Meier survival curves. RESULTS: Included were 131 patients. The median follow-up was 4.1 years (interquartile range, 2.1-6.1). During this period, 30 patients (23%) sustained aneurysm-related adverse events. Seal length <10 mm and presence of endoleak were significant risk factors for this end point. Patients were subsequently categorized as low-risk (proximal and distal seal length ≥10 mm and no endoleak, n = 62) or high-risk (seal length <10 mm or presence of endoleak, or both; n = 69). During follow-up, four low-risk patients (3%) and 26 high-risk patients (19%) sustained events (P < .001). Four secondary interventions were required in three low-risk patients, and 31 secondary interventions in 23 high-risk patients. Sac growth was observed in two low-risk patients and in 15 high-risk patients. The 5-year estimates for freedom from aneurysm-related adverse events were 98% for the low-risk group and 52% for the high-risk group. For each diagnosis, 81.7 image examinations were necessary in the low-risk group and 8.2 in the high-risk group. CONCLUSIONS: Our results suggest that the first postoperative CTA provides important information for risk stratification after endovascular aneurysm repair when the Excluder endoprosthesis is used. In patients with adequate seal and no endoleaks, the risk of aneurysm-related adverse events was significantly reduced, resulting in a large number of unnecessary image examinations. Adjusting the imaging protocol beyond 30 days and up to 5 years, based on individual patients' risk, may result in a more efficient and rational postoperative surveillance.

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OBJECTIVE: A familial predisposition to abdominal aortic aneurysms (AAAs) is present in approximately one-fifth of patients. Nevertheless, the clinical implications of a positive family history are not known. We investigated the risk of aneurysm-related complications after endovascular aneurysm repair (EVAR) for patients with and without a positive family history of AAA. METHODS: Patients treated with EVAR for intact AAAs in the Erasmus University Medical Center between 2000 and 2012 were included in the study. Family history was obtained by written questionnaire. Familial AAA (fAAA) was defined as patients having at least one first-degree relative affected with aortic aneurysm. The remaining patients were considered sporadic AAA. Cardiovascular risk factors, aneurysm morphology (aneurysm neck, aneurysm sac, and iliac measurements), and follow-up were obtained prospectively. The primary end point was complications after EVAR, a composite of endoleaks, need for secondary interventions, aneurysm sac growth, acute limb ischemia, and postimplantation rupture. Secondary end points were specific components of the primary end point (presence of endoleak, need for secondary intervention, and aneurysm sac growth), aneurysm neck growth, and overall survival. Kaplan-Meier estimates for the primary end point were calculated and compared using log-rank (Mantel-Cox) test of equality. A Cox-regression model was used to calculate the independent risk of complications associated with fAAA. RESULTS: A total of 255 patients were included in the study (88.6% men; age 72 ± 7 years, median follow-up 3.3 years; interquartile range, 2.2-6.1). A total of 51 patients (20.0%) were classified as fAAA. Patients with fAAA were younger (69 vs 72 years; P = .015) and were less likely to have ever smoked (58.8% vs 73.5%; P = .039). Preoperative aneurysm morphology was similar in both groups. Patients with fAAA had significantly more complications after EVAR (35.3% vs 19.1%; P = .013), with a twofold increased risk (adjusted hazard ratio, 2.1; 95% confidence interval, 1.2-3.7). Secondary interventions (39.2% vs 20.1%; P = .004) and aneurysm sac growth (20.8% vs 9.5%; P = .030) were the most important elements accounting for the difference. Furthermore, a trend toward more type I endoleaks during follow-up was observed (15.6% vs 7.4%; P = .063) and no difference in overall survival. CONCLUSIONS: The current study shows that patients with a familial form of AAA develop more aneurysm-related complications after EVAR, despite similar AAA morphology at baseline. These findings suggest that patients with fAAA form a specific subpopulation and create awareness for a possible increase in the risk of complications after EVAR.

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OBJECT: In 1999 we reported that 94% of unruptured middle cerebral artery (MCA) aneurysms managed prospectively between 1993 and 1997, according to a protocol favoring endovascular coiling, were best treated by surgical clipping. The goal of the current study was to delineate the most appropriate treatment option for unruptured MCA aneurysms today, considering the technical advances in imaging and in endovascular treatment. METHODS: 35 consecutive patients harboring 40 unruptured MCA aneurysms were treated between 1997 and December 2000. Patients with unruptured cerebral aneurysms are managed prospectively according to the same protocol as reported previously [1]: the primary treatment recommendation is endovascular packing with Guglielmi detachable coils (GDCs). Surgical clipping is recommended after failed attempt at coil placement or in the presence of angioanatomical features that contraindicate that type of endovascular therapy. RESULTS: One unruptured MCA aneurysm was treated by endovascular embolization, 37 unruptured MCA aneurysms were clipped, whereas 2 unruptured MCA aneurysms were trapped with simultaneous extracranial-intracranial revascularization. Postoperative angiography revealed complete exclusion of all aneurysms. Preservation of vascular permeability was demonstrated in all clip-reconstructed aneurysms, despite arterial branches frequently originating from the aneurysmal base. Cerebral revascularization of the distal MCA was successful in the 2 patients with giant aneurysms. None of the patients presented permanent disabling complications from the treatment of the unruptured MCA aneurysm. CONCLUSION: Despite major technical advances in imaging and in endovascular treatment of cerebral aneurysms, surgical clipping still is the most efficient treatment for unruptured MCA aneurysms at the beginning of the new millennium.

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INTRODUCTION: The indications for endovascular aortic aneurysm repair (EVAR) are mainly established in hostile abdomen, in patients with significant comorbidities which affect the general operability of the patient and, given the necessary infrastructure, also in ruptured aneurysm. Along to those, we present another possible indication in the presence of a kidney allograft in patients with aortic aneurysm. METHODS: Based on a case report of aorto-biiliac stent-graft repair of an infrarenal aortic aneurysm in a patient with renal allograft, a systematic review of the literature was performed of all similar cases concerning surgical therapy in this constellation. RESULTS: EVAR was performed using an aorto-biiliac system (Zenith) Trifab, COOK) in a 61-year-old male patient 11 years after heterotopic renal allotransplantation in the right iliac fossa. Preoperative renal function was normal. Because the donor renal artery was anastomosed to the recipient's external iliac artery the stent-graft was implanted from the left common femoral artery to minimize temporary allograft ischemia. The intra- and postoperative course was uneventful with a follow-up of presently 12 months. A primary type-II endoleak (retroleak from a lumbar artery) is being treated conservatively so far with embolization being a future option. At present there are 15 cases of EVAR in renal allograft patients that have been reported, all of them being successful. DISCUSSION: All data existing in the literature reported to date as well as our own experience justify the first choice of EVAR in morphologically suitable cases. One major advantage of EVAR in this constellation is the avoidance of aortic cross clamping which poses the graft at risk of ischemia. Long-term results will be most important for definite assessment of EVAR. However, contrast media application during the operation and for CT surveillance should be considered as a major disadvantage.

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OBJECTIVE: Anemia is a common comorbid condition in various inflammatory states and an established predictor of mortality in patients with chronic heart failure, ischemic heart disease, and end-stage renal disease. The present study of patients with abdominal aortic aneurysm (AAA) undergoing endovascular repair (EVAR) assessed the relationships between baseline hemoglobin concentration and AAA size, as well as anemia and long-term survival. METHODS: Between March 1994 and November 2006, 711 patients (65 women, mean age 75.8 +/- 7.8 years) underwent elective EVAR. Anemia was defined as a hemoglobin level <13 g/dL in men and <12 g/dL in women. Post-EVAR mean follow-up was 48.3 +/- 32.0 months. Association of hemoglobin level with AAA size was assessed with multiple linear regression. Mortality was determined with use of the internet-based Social Security Death Index and the electronic hospital record. Kaplan-Meier survival curves of anemic and nonanemic patient groups were compared by the log-rank method. Multivariable logistic regression models were used to determine the influence of anemia on vital status after EVAR. RESULTS: A total of 218/711 (30.7%) of AAA patients undergoing EVAR had anemia at baseline. After adjustment for various risk factors, hemoglobin level was inversely related to maximum AAA diameter (beta: - .144, 95%-CI: -1.482 - .322, P = .002). Post-EVAR survival was 65.5% at 5 years and 44.4% at 10 years. In long-term follow-up, survival was significantly lower in patients with anemia as compared to patients without anemia (P < .0001 by log-rank). Baseline hemoglobin levels were independently related to long-term mortality in multivariable Cox regression analysis adjusted for various risk factors (adjusted HR: 0.866, 95% CI: .783 to .958, P = .005). Within this model, statin use (adjusted HR: .517, 95% CI: .308 to .868, P = .013) was independently related to long-term survival, whereas baseline AAA diameter (adjusted HR: 1.022, 95% CI: 1.009 to 1.036, P = .001) was an independently associated with increased mortality. CONCLUSIONS: Baseline hemoglobin concentration is independently associated with AAA size and reduced long-term survival following EVAR. Thus, the presence or absence of anemia offers a potential refinement of existing risk stratification instruments.

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PURPOSE: To elucidate the association of impaired pulmonary status (IPS) and diabetes mellitus (DM) with clinical outcome and the incidences of aortic neck dilatation and type I endoleak after elective endovascular infrarenal aortic aneurysm repair (EVAR). METHODS: In 164 European institutions participating in the EUROSTAR registry, 6383 patients (5985 men; mean age 72.4+/-7.6 years) underwent EVAR. Patients were divided into patients without versus with IPS or with/without DM. Clinical assessment and contrast-enhanced computed tomography (CT) were performed at 1, 3, 6, 12, 18, and 24 months and annually thereafter. Cumulative endpoint analysis comprised death, aortic rupture, type I endoleak, endovascular reintervention, and surgical conversion. RESULTS: Prevalence of IPS was 2733/6383 (43%) and prevalence of DM was 810/6383 (13%). Mean follow-up was 21.1+/-18.4 months. Thirty-day mortality, AAA rupture, and conversion rates did not differ between patients with versus without IPS and between patients with versus without DM. All-cause and AAA-related mortality, respectively, were significantly higher in patients with IPS compared to patients with normal pulmonary status (31.0% versus 19.0%, p<0.0001 and 6.8% versus 3.3%, p = 0.0057) throughout follow-up. In multivariate analysis adjusted for smoking, age, gender, comorbidities, fitness for open repair, co-existing common iliac aneurysm, neck and aneurysm size, arterial angulations, aneurysm classification, endograft oversizing >or=15%, and type of stent-graft, the presence of IPS was not associated with significantly higher rates of aortic neck dilatation (30.6% versus 38.0%, p>0.05) and did not influence cumulative rates of type I endoleak, endovascular reintervention, or conversion to open surgery (p>0.05). Similarly, the presence of DM did not influence the above-mentioned study endpoints. CONCLUSION: In contrast to observations regarding the natural course of AAAs, impaired pulmonary status does not negatively influence aortic neck dilatation, while the presence of diabetes does not protect from these dismal events after EVAR.

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Compared with the coronary setting, knowledge about antithrombotic therapies after endovascular treatment (EVT) is inadequate in patients with peripheral artery disease (PAD). Based on a review of trials and guidelines, which is summarized in this article, there is scant evidence that antithrombotic drugs improve outcome after peripheral EVT. To address this knowledge gap, the randomized, open-label, multinational edoxaban in patients with Peripheral Artery Disease (ePAD) study (ClinicalTrials.gov identifier NCT01802775) was designed to explore the safety and efficacy of a combined regimen of antiplatelet therapy with clopidogrel and anticoagulation with edoxaban, a selective and direct factor Xa inhibitor, both combined with aspirin. As of July 2014, 203 patients (144 men; mean age 67 years) from 7 countries have been enrolled. These patients have been allocated to once-daily edoxaban [60 mg for 3 months (or 30 mg in the presence of factors associated with increased exposure)] or clopidogrel (75 mg/d for 3 months). All patients received aspirin (100 mg/d) for the 6-month duration of the study. The primary safety endpoint is major or clinically relevant nonmajor bleeding; the primary efficacy endpoint is restenosis or reocclusion at the treated segment(s) measured at 1, 3, and 6 months using duplex ultrasound scanning. All outcomes will be assessed and adjudicated centrally in a masked fashion. The ePAD study is the first of its kind to investigate a combined regimen of antiplatelet therapy and anticoagulation through factor Xa inhibition with edoxaban.

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Feature selection is important in medical field for many reasons. However, selecting important variables is a difficult task with the presence of censoring that is a unique feature in survival data analysis. This paper proposed an approach to deal with the censoring problem in endovascular aortic repair survival data through Bayesian networks. It was merged and embedded with a hybrid feature selection process that combines cox's univariate analysis with machine learning approaches such as ensemble artificial neural networks to select the most relevant predictive variables. The proposed algorithm was compared with common survival variable selection approaches such as; least absolute shrinkage and selection operator LASSO, and Akaike information criterion AIC methods. The results showed that it was capable of dealing with high censoring in the datasets. Moreover, ensemble classifiers increased the area under the roc curves of the two datasets collected from two centers located in United Kingdom separately. Furthermore, ensembles constructed with center 1 enhanced the concordance index of center 2 prediction compared to the model built with a single network. Although the size of the final reduced model using the neural networks and its ensembles is greater than other methods, the model outperformed the others in both concordance index and sensitivity for center 2 prediction. This indicates the reduced model is more powerful for cross center prediction.

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Abdominal aortic aneurysm is the pathological dilation of the abdominal tract of the aorta and, if left untreated, could undergo rupture with a mortality rate of up to 90%. EVAR is the most common method for AAA treatment consisting in the internal coverage of the aorta with a metallic stent to isolate the aneurysmatic segment from the systemic circulation. Although EVAR technical success rate is high, reinterventions are common. Among the causes of reinterventions typeII endoleaks are the most frequent and consist in retrograde blood flow into the aneurysmal sac from collateral aortic branches. Continued perfusion of the aneurysm sac may lead to aneurysm rupture, therefore AAA sac embolization is performed using metallic coils. However, the presence of artifacts caused by the presence of metallic coils is a limitation because they are radiopaque and can hamper the endoleak during imaging follow-up. This study is aimed at developing a biocompatible hydrogel that could be injected into the aneurysmal sac and may allow a selective intraprocedural sac embolization to reduce post procedural typeII endoleak and eventual AAA rupture. P(BT75BSI25) was synthesized by polycondensation and its biocompatibility tested to assess whether the polymers had no toxic effects. HUVEC cell line was used to mimic the environment in which the polymer would be in contact with, PBS was used as a positive control and MTT assay was performed to evaluate cellular viability after being in contact with the hydrogel. MTT assay showed no significant difference between PBS and P(BT75BSI25), thus the polymer is biocompatible, as confirmed by the analysis of apoptosis by flow cytometry. An aromatic copolymer was obtained via polycondensation and was found to be biocompatible in contact with endothelial cells. This suggests that the hydrogel could be potentially used in the clinical setting for the treatment of type II endoleak after EVAR.

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The present paper describes a novel, simple and reliable differential pulse voltammetric method for determining amitriptyline (AMT) in pharmaceutical formulations. It has been described for many authors that this antidepressant is electrochemically inactive at carbon electrodes. However, the procedure proposed herein consisted in electrochemically oxidizing AMT at an unmodified carbon nanotube paste electrode in the presence of 0.1 mol L(-1) sulfuric acid used as electrolyte. At such concentration, the acid facilitated the AMT electroxidation through one-electron transfer at 1.33 V vs. Ag/AgCl, as observed by the augmentation of peak current. Concerning optimized conditions (modulation time 5 ms, scan rate 90 mV s(-1), and pulse amplitude 120 mV) a linear calibration curve was constructed in the range of 0.0-30.0 μmol L(-1), with a correlation coefficient of 0.9991 and a limit of detection of 1.61 μmol L(-1). The procedure was successfully validated for intra- and inter-day precision and accuracy. Moreover, its feasibility was assessed through analysis of commercial pharmaceutical formulations and it has been compared to the UV-vis spectrophotometric method used as standard analytical technique recommended by the Brazilian Pharmacopoeia.

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We have shown how the analysis of the angiotomography reconstruction through OsiriX program has assisted in endovascular perioperative programming. We presented its application in situations when an unexpected existence of metallic overlapping artifact (orthopedic osteosynthesis) compromised the adequate visualization of the arterial lesion during the procedure. Through manipulation upon OsiriX software, with assistance of preview under virtual fluoroscopy, it was possible to obtain the angles that would avoid this juxtaposition. These angles were reproduced in the C-arm, allowing visualization of the occluded segment, reducing the need for repeated image acquisitions and contrast overload, allowing the continuation of the procedure.

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Health economic evaluations require estimates of expected survival from patients receiving different interventions, often over a lifetime. However, data on the patients of interest are typically only available for a much shorter follow-up time, from randomised trials or cohorts. Previous work showed how to use general population mortality to improve extrapolations of the short-term data, assuming a constant additive or multiplicative effect on the hazards for all-cause mortality for study patients relative to the general population. A more plausible assumption may be a constant effect on the hazard for the specific cause of death targeted by the treatments. To address this problem, we use independent parametric survival models for cause-specific mortality among the general population. Because causes of death are unobserved for the patients of interest, a polyhazard model is used to express their all-cause mortality as a sum of latent cause-specific hazards. Assuming proportional cause-specific hazards between the general and study populations then allows us to extrapolate mortality of the patients of interest to the long term. A Bayesian framework is used to jointly model all sources of data. By simulation, we show that ignoring cause-specific hazards leads to biased estimates of mean survival when the proportion of deaths due to the cause of interest changes through time. The methods are applied to an evaluation of implantable cardioverter defibrillators for the prevention of sudden cardiac death among patients with cardiac arrhythmia. After accounting for cause-specific mortality, substantial differences are seen in estimates of life years gained from implantable cardioverter defibrillators.

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Squamous cell carcinoma is the most common neoplasm of the larynx, and its evolution depends on tumor staging. Vascular endothelial growth factor is a marker of angiogenesis, and its expression may be related to increased tumor aggressiveness, as evidenced by the presence of cervical lymphatic metastases. To evaluate the expression of the vascular endothelial growth factor marker in non-glottic advanced squamous cell carcinoma of the larynx (T3/T4) and correlate it with the presence of cervical lymph node metastases. Retrospective clinical study and immunohistochemical analysis of vascular endothelial growth factor through the German scale of immunoreactivity in products of non-glottic squamous cell carcinomas. This study analyzed 15 cases of advanced non-glottic laryngeal tumors (T3/T4), four of which exhibited cervical lymphatic metastases. There was no correlation between vascular endothelial growth factor expression and the presence of cervical metastases. Although vascular endothelial growth factor was expressed in a few cases, there was no correlation with the spread of cervical lymph metastases.

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The present study compared the accuracy of three electronic apex locators (EALs) - Elements Diagnostic®, Root ZX® and Apex DSP® - in the presence of different irrigating solutions (0.9% saline solution and 1% sodium hypochlorite). The electronic measurements were carried out by three examiners, using twenty extracted human permanent maxillary central incisors. A size 10 K file was introduced into the root canals until reaching the 0.0 mark, and was subsequently retracted to the 1.0 mark. The gold standard (GS) measurement was obtained by combining visual and radiographic methods, and was set 1 mm short of the apical foramen. Electronic length values closer to the GS (± 0.5 mm) were considered as accurate measures. Intraclass correlation coefficients (ICCs) were used to verify inter-examiner agreement. The comparison among the EALs was performed using the McNemar and Kruskal-Wallis tests (p < 0.05). The ICCs were generally high, ranging from 0.8859 to 0.9657. Similar results were observed for the percentage of electronic measurements closer to the GS obtained with the Elements Diagnostic® and the Root ZX® EALs (p > 0.05), independent of the irrigating solutions used. The measurements taken with these two EALs were more accurate than those taken with Apex DSP®, regardless of the irrigating solution used (p < 0.05). It was concluded that Elements Diagnostic® and Root ZX® apex locators are able to locate the cementum-dentine junction more precisely than Apex DSP®. The presence of irrigating solutions does not interfere with the performance of the EALs.