Background Low-profile (LP) stent grafts are now commercially available in Europe for endovascular aortic aneurysm repair (EVAR). In this study the midterm outcomes and characteristics of patients ...treated with this last generation of stent grafts were compared with a cohort of patients treated with “standard-profile” (SP) stent grafts. Methods The current study enrolled all patients treated for elective EVAR by the SP Zenith Flex stent graft (Cook Medical, Bloomington, Ind) between March 2010 and November 2011 and patients treated for elective EVAR by the Zenith LP stent graft (Cook Medical) between November 2011 and March 2013. All patients had a follow-up >18 months. Preoperative computed tomography angiograms were analyzed on a dedicated three-dimensional workstation. All data were prospectively collected in an electronic database and retrospectively analyzed. A comparative study was conducted. Results The present study included 208 patients (107 SP and 101 LP). Patients' physiologic characteristics were similar in both groups. The iliac anatomy was considered “more challenging” in LP patients: respectively, 7% and 22% ( P = .002) of SP and LP patients had bilateral external iliac diameter <7 mm; and 16% and 34% ( P = .005) had a combination of an external iliac diameter <7 mm and an iliac tortuosity ratio index >1.5. No 30-day deaths were documented. The 24-month freedom from reintervention and overall survival rates after SP and LP were, respectively, 88% and 91% ( P = .450) and 92% and 96% ( P = .153). The 24-month rates for freedom from sac expansion and from limb occlusion were 96.4% and 98.7% ( P = .320) and 92% and 95% ( P = .293), respectively. One patient in each group presented with a type I endoleak during follow-up, and two LP patients presented with a type III endoleak ( P = .235). Conclusions This study demonstrates that the last-generation LP stent grafts have favorable midterm outcomes similar to SP stent grafts despite being used to treat more patients with unfavorable iliac anatomy.
Background One explanation for the high burden of allergic and autoimmune diseases in industrialized countries is inappropriate immune development under modern environmental conditions. There is ...increasing evidence that the process of immune deviation already begins in utero , but the underlying immunologic mechanisms are not clear. Objective We sought to identify differences in the function of neonatal antigen-presenting cells (APCs) in children born in settings that are more traditional versus those of modern societies. Methods Cord blood mononuclear cells were collected from newborns from Papua New Guinea (PNG; traditional) and Australia (modern) and compared for differences in APCs and T-cell phenotype and function. Results Australian cord naive T cells (CD4+ CD25− CD127+ cells) showed an enhanced and more rapid proliferative response in an autologous, APC-dependent culture system, a result of differences in neonatal APCs rather than T-cell function. This included an increased capacity to process antigen and to upregulate activation markers after stimulation. In contrast, resting PNG APCs exhibited higher baseline levels of activation and inhibitory markers and were less responsive or nonresponsive to stimulation in vitro. Conclusions This study supports the hypothesis that prenatal environments can influence the developing immune system in utero . Children born under modern environmental conditions exhibit increased APC reactivity at birth compared with children born under traditional environmental conditions. The functionally more quiescent nature of PNG neonatal APCs might protect against the development of harmful inflammatory responses in early life.
Background The protective effect of Mycobacterium bovis BCG vaccination against infection and atopy varies between populations. Objective To identify differences in neonatal responses to BCG between ...diverse populations and study longitudinal associations with memory T-cell responses. Methods Cord blood mononuclear cells were collected from Papua New Guinean (PNG) and Western Australian (WA) newborns. Toll-like receptor (TLR)-2, TLR4, and TLR9 mRNA expression and in vitro BCG-stimulated (±IFN-γ priming) innate cytokine responses were compared. When PNG infants were 3 months old, PBMCs were stimulated in vitro with Mycobacterium -purified protein derivative (PPD) to determine memory T-cell responses. Results BCG-induced IL-10 and IFN-γ responses were significantly higher in cord blood mononuclear cells of PNG newborns, and TLR2 and TLR9 expression was significantly higher and TLR4 expression lower compared with WA newborns. High neonatal IL-10 and low IFN-γ responses to BCG were found to promote the development of PPD-memory TH 2 responses in infancy, whereas neonatal BCG-TNFα responses inhibited the development of PPD-IL 10 responses. When primed with IFN-γ, BCG-induced TNF-α, IL-12p70, and in particular IFN-γ responses were enhanced to a significantly higher extent in WA than in PNG newborns. In response to IFN-γ priming and BCG stimulation, natural killer cells of WA newborns produced IFN-γ, whereas natural killer cells of PNG newborns contributed only indirectly to this response. Conclusion Neonatal BCG-related innate immune responses control the differentiation of TH memory responses and vary between populations. This may explain differences in the effects of BCG vaccination between populations.
Objective To assess the relationship between the annual caseload of elective open abdominal aortic aneurysm (AAA) repairs performed by individual surgeons and mortality. Methods PubMed, EMBASE, and ...the Cochrane library were searched for articles on the volume-outcome relationship in AAA surgery. The review conformed to the QUOROM statement. The data were meta-analyzed to compare the mortality rates of higher- and lower-volume surgeons. A critical volume threshold was calculated for better practice. Results Fourteen relevant articles were retrieved from the searches. A systematic review was performed, and six were meta-analyzed. A total of 115,273 elective open AAA repairs were considered, with a mean mortality rate of 5.56%. Significant relationships between higher surgeon caseload and lower mortality were demonstrated in 12 of 14 studies. From the meta-analysis, the pooled effect estimate was an odds ratio of 0.56 (95% confidence interval, 0.54-0.57) in favor of higher-volume surgeons. A critical volume threshold was identified as 13 cases per annum for individual surgeons. Conclusions As surgeons performed higher annual volumes of elective open AAA repairs, significantly lower mortality rates were demonstrated. Surgeons wishing to perform elective AAA repairs should achieve a minimum case volume of 13 repairs per annum.
Background Different methods have been used to assess remodeling of the thoracic aorta after endovascular treatment of Stanford type B aortic dissections. Changes in morphology may be described using ...diameter, area, or volume. The aim of this study was to determine if aortic diameter measurements could be used to approximate aortic area in order to refine reporting standards. Methods The study population encompassed 100 patients enrolled in the VIRTUE registry (designed to assess thoracic endografting with the Valiant Stent Graft System Medtronic, Minneapolis, MN for the treatment of type B aortic dissections). Diameter and area measurements of the true lumen, false lumen, and whole aorta were made using three-dimensional computed tomographic (3D CT) workstations, at different anatomic locations. Measurements included preoperative, postoperative, and follow-up scans. The Pearson test was used to determine general correlation between diameter and volume at each location. Scatter plots were drawn and linear regression models were used to draw a line of best fit. Comparison of these with nonlinear models was performed. Results Aortic true and false lumen diameter and area showed good correlation ( p < 0.001) in the majority of anatomic locations. This relationship was present preoperatively and during follow-up ( p < 0.001). The linear regression models fit well with high R2 values. At very large aortic sizes nonlinear models were a slightly better fit, but this was not significant. Conclusions Aortic diameter measurements correlate with luminal areas in patients with type B aortic dissection. This implies area increases proportionately with diameter over time. Therefore, diameter measurements using multiplanar reconstructions based on a central luminal line appear to be adequate when assessing aortic remodeling after endovascular treatment of aortic dissection.
IMPORTANCE: The quality of routine care for children is rarely assessed, and then usually in single settings or for single clinical conditions. OBJECTIVE: To estimate the quality of health care for ...children in Australia in inpatient and ambulatory health care settings. DESIGN, SETTING, AND PARTICIPANTS: Multistage stratified sample with medical record review to assess adherence with quality indicators extracted from clinical practice guidelines for 17 common, high-burden clinical conditions (noncommunicable n = 5, mental health n = 4, acute infection n = 7, and injury n = 1), such as asthma, attention-deficit/hyperactivity disorder, tonsillitis, and head injury. For these 17 conditions, 479 quality indicators were identified, with the number varying by condition, ranging from 9 for eczema to 54 for head injury. Four hundred medical records were targeted for sampling for each of 15 conditions while 267 records were targeted for anxiety and 133 for depression. Within each selected medical record, all visits for the 17 targeted conditions were identified, and separate quality assessments made for each. Care was evaluated for 6689 children 15 years of age and younger who had 15 240 visits to emergency departments, for inpatient admissions, or to pediatricians and general practitioners in selected urban and rural locations in 3 Australian states. These visits generated 160 202 quality indicator assessments. EXPOSURES: Quality indicators were identified through a systematic search of local and international guidelines. Individual indicators were extracted from guidelines and assessed using a 2-stage Delphi process. MAIN OUTCOMES AND MEASURES: Quality of care for each clinical condition and overall. RESULTS: Of 6689 children with surveyed medical records, 53.6% were aged 0 to 4 years and 55.5% were male. Adherence to quality of care indicators was estimated at 59.8% (95% CI, 57.5%-62.0%; n = 160 202) across the 17 conditions, ranging from a high of 88.8% (95% CI, 83.0%-93.1%; n = 2638) for autism to a low of 43.5% (95% CI, 36.8%-50.4%; n = 2354) for tonsillitis. The mean adherence by condition category was estimated as 60.5% (95% CI, 57.2%-63.8%; n = 41 265) for noncommunicable conditions (range, 52.8%-75.8%); 82.4% (95% CI, 79.0%-85.5%; n = 14 622) for mental health conditions (range, 71.5%-88.8%); 56.3% (95% CI, 53.2%-59.4%; n = 94 037) for acute infections (range, 43.5%-69.8%); and 78.3% (95% CI, 75.1%-81.2%; n = 10 278) for injury. CONCLUSIONS AND RELEVANCE: Among a sample of children receiving care in Australia in 2012-2013, the overall prevalence of adherence to quality of care indicators for important conditions was not high. For many of these conditions, the quality of care may be inadequate.
Objective Endovascular aneurysm repair (EVAR) has reduced early adverse outcomes from abdominal aortic aneurysm (AAA) repair. Preferential use of EVAR may have altered the profile of patients who ...undergo open repair. The validity of scoring systems such as the Glasgow Aneurysm Score (GAS), devised when open surgery was the only treatment, required reappraisal. Methods Patients were identified from a database of patients undergoing elective infrarenal aneurysm repair at seven United Kingdom centers, and the GAS was calculated for each patient. Discrimination and calibration were calculated to determine the performance of the model in this setting using the C statistic, tertile analysis, and the χ2 test. Univariate analysis was performed to determine if a new iteration of the GAS could be produced. Results We identified 330 patients who met the inclusion criteria. There were 18 deaths ≤30 days of surgery (5.4%). The average (standard deviation) GAS was 78.6 (8.8) for the survivors and 81.9 (10.4) for nonsurvivors ( P = .122). The C statistic was 0.625 (95% confidence interval, 0.481-0.769; P = .75) suggesting a discriminatory ability not much better than chance alone. Despite this, calibration of the model was good. There was no significant difference in the comorbidities of either group, so no recalibration of the GAS could be performed. Conclusion The GAS did not discriminate between survivors and nonsurvivors after open AAA repair in this cohort. In the era of EVAR, it is possible that the GAS does not predict the outcome of open AAA repair. An alternative explanation is that patients with risk factors for poor outcomes from EVAR, such as adverse AAA morphology, are being selected out for open repair.
Introduction It is difficult to reliably predict abdominal aortic aneurysm (AAA) expansion and rupture in individuals. There is increasing interest in the role of patient-specific biomechanical ...profiling of AAA development and rupture. This review examines evidence to support the use of biomechanical profiling in AAA. Methods The literature was systematically reviewed to examine the evidence to support the role of patient-specific biomechanical profiles in the management of patients with AAA. A search of Medline, Medline in process and other nonindexed citations, and EMBASE was performed for articles published from January 1980 to December 2008. The search strategy retrieved 2410 titles. After exclusions, 83 articles were reviewed in full and form the basis of this review. Results There is increasing evidence that patient-specific biomechanical factors may be more reliable in predicting AAA rupture than currently available clinical and biochemical parameters. Wall stress determination using finite element analysis is consistently higher in symptomatic and ruptured AAA. Recent improvements in computational methodology and advances in imaging and processing technology have increased the power of these biomechanical factors in predicting AAA expansion and rupture. Conclusions Major progress has been made in the development of biomechanical profiles for AAA. Large population-based studies for validation of patient-specific biomechanical profiles with rupture risk assessment and tailored decision making are now indicated, particularly with the introduction of AAA screening programs.
Background Gene-environment interactions play central roles in controlling postnatal maturation of immune function, but their effects on infant vaccine responses are unknown. Genetic variants ...associated with atopy and the environmental factor of exposure to parental smoking (PS) of tobacco independently alter immune responses. Objective We sought to investigate the hypothesis that genetic variants associated with atopy and their interaction with PS influence infant vaccine responsiveness. Methods In 200 infants with parental atopic history, relationships were sought between polymorphisms in the IL-4, IL-4 receptor α (IL-4Rα), and IL-13 genes; PS; and immune responses to diphtheria/tetanus vaccination. Results Analyses stratified by PS unmasked negative associations between atopic alleles of these genes and vaccine outcomes. The most consistent involved the IL-4Rα 551 QR/QQ genotypes, which were associated with reduced IgG levels ( P = .02) and T-cell responses (IFN-γ, P = .002; IL-10, P = .01; 1L-13, P = .01; IL-5, P = .06) to tetanus toxoid and parallel reductions in polyclonal T-cell responses and innate immune responses in PS-exposed infants. Conclusion PS potentiates suppressive effects of variants in immune response genes in children. These effects are not observed in the absence of this exposure. Ultimately, this finding might have implications for infant vaccination in countries with high smoking rates. It might also have broader implications in relation to environmental toxicology because it demonstrates specific mechanisms through which the developing immune system might be differentially sensitive to low-level toxicant exposures. Clinical implications PS interacts with genes associated with atopy to impair vaccine responses. These interactions might have vaccine design and public health implications.
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