Alberto Vidal-Diez

Mortality from ruptured abdominal aortic aneurysms: clinical lessons from a comparison of outcomes in England and the USA

BACKGROUND The outcome of patients with ruptured abdominal aortic aneurysm (rAAA) varies by country. Study of practice differences might allow the formulation of pathways to improve care. METHODS We compared data from the Hospital Episode Statistics for England and the Nationwide Inpatient Sample for the USA for patients admitted to hospital with rAAA from 2005 to 2010. Primary outcomes were in-hospital mortality, mortality after intervention, and decision to follow non-corrective treatment. In-hospital mortality and the rate of non-corrective treatment were analysed by binary logistic regression for each health-care system, after adjustment for age, sex, year, and Charlson comorbidity index. FINDINGS The study included 11,799 patients with rAAA in England and 23,838 patients with rAAA in the USA. In-hospital mortality was lower in the USA than in England (53·05% [95% CI 51·26-54·85] vs 65·90%; p<0·0001). Intervention (open or endovascular repair) was offered to a greater proportion of cases in the USA than in England (19,174 [80·43%] vs 6897 [58·45%]; p<0·0001) and endovascular repair was more common in the USA than in England (4003 [20·88%] vs 589 [8·54%]; p<0·0001). Postintervention mortality was similar in both countries (41·77% for England and 41·65% for USA). These observations persisted in age-matched and sex-matched comparisons. In both countries, reduced mortality was associated with increased use of endovascular repair, increased hospital caseload (volume) for rAAA, high hospital bed capacity, hospitals with teaching status, and admission on a weekday. INTERPRETATION In-hospital survival from rAAA, intervention rates, and uptake of endovascular repair are lower in England than in the USA. In England and the USA, the lowest mortality for rAAA was seen in teaching hospitals with larger bed capacities and doing a greater proportion of cases with endovascular repair. These common factors suggest strategies for improving outcomes for patients with rAAA. FUNDING None.

Predicting aortic complications after endovascular aneurysm repair

Lifelong surveillance is standard after endovascular repair of abdominal aortic aneurysm (EVAR), but remains costly, heterogeneous and poorly calibrated. This study aimed to develop and validate a scoring system for aortic complications after EVAR, informing rationalized surveillance.

Impact of processing on the bioavailability and vascular effects of blueberry (poly)phenols

SCOPE Blueberries are a rich source of flavonoids and phenolic acids. Currently, little information is available regarding the impact of processing on the bioavailability and the bioactivity of blueberry (poly)phenols. METHODS AND RESULTS In a randomized, controlled crossover trial, ten healthy volunteers consumed (a) blueberry-containing baked products, (b) an unprocessed blueberry drink containing the same amount of freeze-dried blueberry powder as used in the baked products, and (c) matched control baked products. Endothelial function was measured as flow-mediated dilation (FMD) and plasma samples taken at baseline and at 1, 2, 4, and 6 h postconsumption. Although processing did not significantly change the total (poly)phenolic amount, the processed products contained significantly less anthocyanins (-42%), more chlorogenic acid (23%), no flavanol nonamers or decamers, and significantly more flavanol dimers and trimers (36% and 28%, respectively). FMD increased after 1, 2, and 6 h consumption of the baked products to a similar degree as the unprocessed blueberries, despite significant differences in the levels of individual plasma metabolites. No changes were observed after the consumption of the control product. CONCLUSION Careful processing can preserve important biological activities of blueberries despite changing the blueberry (poly)phenol composition and plasma metabolite profile.

Association of hospital structures with mortality from ruptured abdominal aortic aneurysm

There is significant variation in the mortality rates of patients with a ruptured abdominal aortic aneurysm (rAAA) admitted to hospital in England. This study sought to investigate whether modifiable differences in hospital structures and processes were associated with differences in patient outcome.

Blueberry intervention improves vascular reactivity and lowers blood pressure in high-fat-, high-cholesterol-fed rats.

Growing evidence suggests that intake of flavonoid-containing foods may exert cardiovascular benefits in human subjects. We have investigated the effects of a 10-week blueberry (BB) supplementation on blood pressure (BP) and vascular reactivity in rats fed a high-fat/high-cholesterol diet, known to induce endothelial dysfunction. Rats were randomly assigned to follow a control chow diet, a chow diet supplemented with 2 % (w/w) BB, a high-fat diet (10 % lard; 0·5 % cholesterol) or the high fat plus BB for 10 weeks. Rats supplemented with BB showed significant reductions in systolic BP (SBP) of 11 and 14 %, at weeks 8 and 10, respectively, relative to rats fed the control chow diet (week 8 SBP: 107·5 (SEM 4·7) v. 122·2 (SEM 2·1) mmHg, P= 0·018; week 10 SBP: 115·0 (SEM 3·1) v. 132·7 (SEM 1·5) mmHg, P< 0·0001). Furthermore, SBP was reduced by 14 % in rats fed with the high fat plus 2 % BB diet at week 10, compared to those on the high-fat diet only (SBP: 118·2 (SEM 3·6) v. 139·5 (SEM 4·5) mmHg, P< 0·0001). Aortas harvested from BB-fed animals exhibited significantly reduced contractile responses (to L-phenylephrine) compared to those fed the control chow or high-fat diets. Furthermore, in rats fed with high fat supplemented with BB, aorta relaxation was significantly greater in response to acetylcholine compared to animals fed with the fat diet. These data suggest that BB consumption can lower BP and improve endothelial dysfunction induced by a high fat, high cholesterol containing diet.

Examining Deterrence and Backlash Effects in Counter-Terrorism: The Case of ETA

Scholars are increasingly drawing on models and theories from the field of Criminology to offer new insights on terrorist violence. A particularly useful framework by LaFree, Dugan, and Korte works from the assumption that illegal behaviour can be affected by the threat and/or imposition of punishment. It sees the results of the governments intervention in terms of deterrence (states repressive action leads to a reduction in terrorism violence), and backlash (states repressive action leads to defiance and retaliation, and to an upsurge of terrorism violence). This article applies this model to a case study of the governments responses to Euzkadi Ta Askatasuna (ETA). It uses a variation of survival analysis technique—Series Hazard—to assess the impact of six major initiatives on the risk of new ETA attacks in the period from 1977 to 2010. Mostly, the results provide support for both backlash interpretations, although important questions regarding interpretation are raised.

Cardiovascular risk prevention and all-cause mortality in primary care patients with an abdominal aortic aneurysm

Perioperative mortality is low for patients undergoing abdominal aortic aneurysm (AAA) repair, but long‐term survival remains poor. Although patients diagnosed with AAA have a significant burden of cardiovascular disease and associated risk factors, there is limited understanding of the contribution of cardiovascular risk management to long‐term survival.

Elective Open Suprarenal Aneurysm Repair in England from 2000 to 2010 an Observational Study of Hospital Episode Statistics

Background Open surgery is widely used as a benchmark for the results of fenestrated endovascular repair of complex abdominal aortic aneurysms (AAA). However, the existing evidence stems from single-centre experiences, and may not be reproducible in wider practice. National outcomes provide valuable information regarding the safety of suprarenal aneurysm repair. Methods Demographic and clinical data were extracted from English Hospital Episodes Statistics for patients undergoing elective suprarenal aneurysm repair from 1 April 2000 to 31 March 2010. Thirty-day mortality and five-year survival were analysed by logistic regression and Cox proportional hazards modeling. Results 793 patients underwent surgery with 14% overall 30-day mortality, which did not improve over the study period. Independent predictors of 30-day mortality included age, renal disease and previous myocardial infarction. 5-year survival was independently reduced by age, renal disease, liver disease, chronic pulmonary disease, and known metastatic solid tumour. There was significant regional variation in both 30-day mortality and 5-year survival after risk-adjustment. Regional differences in outcome were eliminated in a sensitivity analysis for perioperative outcome, conducted by restricting analysis to survivors of the first 30 days after surgery. Conclusions Elective suprarenal aneurysm repair was associated with considerable mortality and significant regional variation across England. These data provide a benchmark to assess the efficacy of complex endovascular repair of supra-renal aneurysms, though cautious interpretation is required due to the lack of information regarding aneurysm morphology. More detailed study is required, ideally through the mandatory submission of data to a national registry of suprarenal aneurysm repair.

An Artificial Neural Network Stratifies the Risks of Reintervention and Mortality after Endovascular Aneurysm Repair; a Retrospective Observational study.

Background Lifelong surveillance after endovascular repair (EVAR) of abdominal aortic aneurysms (AAA) is considered mandatory to detect potentially life-threatening endograft complications. A minority of patients require reintervention but cannot be predictively identified by existing methods. This study aimed to improve the prediction of endograft complications and mortality, through the application of machine-learning techniques. Methods Patients undergoing EVAR at 2 centres were studied from 2004-2010. Pre-operative aneurysm morphology was quantified and endograft complications were recorded up to 5 years following surgery. An artificial neural networks (ANN) approach was used to predict whether patients would be at low- or high-risk of endograft complications (aortic/limb) or mortality. Centre 1 data were used for training and centre 2 data for validation. ANN performance was assessed by Kaplan-Meier analysis to compare the incidence of aortic complications, limb complications, and mortality; in patients predicted to be low-risk, versus those predicted to be high-risk. Results 761 patients aged 75 +/- 7 years underwent EVAR. Mean follow-up was 36+/- 20 months. An ANN was created from morphological features including angulation/length/areas/diameters/volume/tortuosity of the aneurysm neck/sac/iliac segments. ANN models predicted endograft complications and mortality with excellent discrimination between a low-risk and high-risk group. In external validation, the 5-year rates of freedom from aortic complications, limb complications and mortality were 95.9% vs 67.9%; 99.3% vs 92.0%; and 87.9% vs 79.3% respectively (p<0.001) Conclusion This study presents ANN models that stratify the 5-year risk of endograft complications or mortality using routinely available pre-operative data.

Predicting Mid-term All-cause Mortality in Patients Undergoing Elective Endovascular Repair of a Descending Thoracic Aortic Aneurysm.

Introduction: All-cause mortality in patients after repair of aortic aneurysms of the descending thoracic aorta thoracic endovascular aortic repair (TEVAR) is relatively high at mid-term follow-up. The aim of this study was to derive and validate a system that could predict all-cause mortality after TEVAR to aid with patient selection. Methods: The MOTHER database contained 625 patients that underwent elective surgery for descending thoracic aortic aneurysms. Univariate analysis identified preoperative factors associated with mid-term all-cause mortality, and a Cox proportional hazards model was developed. The model was internally validated using Kaplan-Meier comparison of observed vs predicted mortality. External validation was performed using a data set from the University of Florida College of Medicine. Results: There were 625 patients that underwent TEVAR for descending thoracic aortic aneurysm in the MOTHER database and 231 in the University of Florida College of Medicine validation set. The mid-term mortality rate at 6 years of follow-up was 34.4% and 34%, respectively. The all-cause mortality risk score was calculated using 0.0398 × (age) + 0.516 × (renal insufficiency) + 0.46 × (previous cerebrovascular disease) + 0.352 × (prior tobacco use) + 0.376 × (number of devices >2) + 0.016 × (maximum aneurysm diameter). Using this score, low-, medium-, and high-risk groups were defined, with predicted survival at 5 years of 80%, 60%, and 40%. Patients at high risk of mid-term all-cause death were identified in the validation cohort using the prediction rule. Conclusions: Identifying patients with a limited life expectancy after TEVAR is possible using a preoperative risk-stratification system. This information can be used to inform decision making regarding when and whether to proceed with TEVAR.