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Summary Background The frequency of secondary interventions after endovascular repair of abdominal aortic aneurysms (AAAs) was assessed and correlated with findings at clinical and imaging examination during follow-up. Methods Data were studied from 1023 patients with a follow-up of 12 months or longer, collected by 56 institutions in a multicentre data registry (EUROSTAR). Surveillance data were provided by the centres between September 1996 and November 1999. Results Overall, 186 patients (18 per cent) had a secondary intervention occurring a mean of 14 months after the initial endograft procedure. Twelve per cent of the interventions were transabdominal, 11 per cent consisted of an extra-anatomic bypass and 76 per cent involved a transfemoral procedure. The rates of freedom from intervention at 1, 3 and 4 years were 89, 67 and 62 per cent respectively. Migration (relative risk (RR) 8·9) and rupture (RR 22·6) were the most frequent causes of secondary transabdominal interventions. Graft limb thrombosis was the principal indication for extra-anatomic bypass (RR 37·5 for clinical evidence of graft limb thrombosis). Endoleak, graft kinking, stenosis or thrombosis and device migration were significant causes for secondary transfemoral interventions (RR 2·5–6·9). Conclusion The high incidence of late secondary interventions is a cause for concern with regard to broad application of endovascular AAA repair, and emphasizes the need for lifelong surveillance. [ABSTRACT FROM AUTHOR]

Focuses on the publication of Eurostar in response for reliable information on outcomes associated with endovascular aneurysm repair (EVAR). Establishment of the Eurostar registry in 1996; Availability of sources of information on EVAR; Issues on the validity of EVAR for treatment of patients with aortic aneurysms.

Atypical EGFR mutations occur in 10%-30% of non-small-cell lung cancer (NSCLC) patients with EGFR mutations and their sensitivity to classical epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKI) is highly heterogeneous. Patients harboring one group of uncommon, recurrent EGFR mutations (G719X, S768I, L861Q) respond to EGFR-TKI. Exon 20 insertions are mostly insensitive to EGFR-TKI but display sensitivity to exon 20 inhibitors. Clinical outcome data of patients with very rare point and compound mutations upon systemic treatments are still sparse to date. In this retrospective, multicenter study of the national Network Genomic Medicine (nNGM) in Germany, 856 NSCLC cases with atypical EGFR mutations including co-occurring mutations were reported from 12 centers. Clinical follow-up data after treatment with different EGFR-TKIs, chemotherapy and immune checkpoint inhibitors were available from 260 patients. Response to treatment was analyzed in three major groups: (i) uncommon mutations (G719X, S7681, L861Q and combinations), (ii) exon 20 insertions and (iii) very rare EGFR mutations (very rare single point mutations, compound mutations, exon 18 deletions, exon 19 insertions). Our study comprises the largest thus far reported real-world cohort of very rare EGFR single point and compound mutations treated with different systemic treatments. We validated higher efficacy of EGFR-TKI in comparison to chemotherapy in group 1 (uncommon), while most exon 20 insertions (group 2) were not EGFR-TKI responsive. In addition, we found TKI sensitivity of very rare point mutations (group 3) and of complex EGFR mutations containing exon 19 deletions or L858R mutations independent of the combination partner. Notably, treatment responses in group 3 (very rare) were highly heterogeneous. Co-occurring TP53 mutations exerted a non-significant trend for a detrimental effect on outcome in EGFR-TKI-treated patients in groups 2 and 3 but not in group 1. Based on our findings, we propose a novel nNGM classification of atypical EGFR mutations. • The EGFR-TKI efficacy of in uncommon EGFR mutations generally considered TKI sensitive was validated. • Complex EGFR mutations containing exon19del or L858R were EGFR-TKI sensitive, independent of the combination partner. • Very rare single and complex mutations, comprising 40% of atypical mutations, show a high heterogeneity of TKI sensitivity. • TP53 co-mutations may confer a detrimental outcome in TKI-treated patients with very rare EGFR mutations and exon20ins. • We propose a novel nNGM classification for atypical EGFR mutations. [ABSTRACT FROM AUTHOR]

Background: The aim was to compare the cardiac response and the incidence of adverse cardiac events during and after endovascular (EVAR) and open (OR) repair of abdominal aortic aneurysms (AAAs). Methods: Seventy-six patients with an AAA suitable for EVAR, and in a general condition allowing open surgery were randomized to EVAR (57 patients) or OR (19 patients). The analysis was on an intention-to-treat basis. Haemodynamic variables were assessed intraoperatively before, during and after aortic occlusion. During the procedure myocardial ischaemia was identified with use of electrocardiography (ECG) and transoesophageal echocardiography (TEE). After operation, cardiac complications were diagnosed by clinical observation, 12-lead ECG at 1 h, 1 day and 7 days, echocardiography at 1 month and measurement of cardiac enzymes. Results: After aortic occlusion, a greater decrease in systemic vascular resistance compared with baseline was observed with OR than with EVAR (- 396 and - 70 dyne s/cm5 respectively; P = 0·03). The stroke work index, as a direct measure of myocardial performance, demonstrated a decrease during OR and an increase during EVAR during aortic occlusion (- 6·6 and + 1·7 g m/m2 respectively; P = 0·03) as well as after aortic occlusion (- 7·6 and + 3·4 g m/m2 respectively; P < 0·01), compared with baseline. The incidence of postoperative clinical cardiac complications was comparable in the two study groups; however, myocardial ischaemia, as observed by ECG and TEE, was observed more frequently in the OR group (ten of 19 versus 15 of 57 patients; P = 0·05). Conclusion: Haemodynamic changes were less severe and there was a lower incidence of myocardial ischaemia during EVAR than during OR. Studies are needed to demonstrate whether this may reduce the operative mortality rate. [ABSTRACT FROM AUTHOR]

Background Long-term survival is similar after open or endovascular repair of abdominal aortic aneurysm. Few data exist on the effect of either procedure on long-term health-related quality of life ( HRQoL) and health status. Methods Patients enrolled in a multicentre randomized clinical trial ( DREAM trial; 2000-2003) in Europe of open repair versus endovascular repair ( EVAR) of abdominal aortic aneurysm were asked to complete questionnaires on health status and HRQoL. HRQoL scores were assessed at baseline and at 13 time points thereafter, using generic tools, the Medical Outcomes Study 36-Item Short-Form Health Survey ( SF-36®) and EuroQol 5D ( EQ-5D™). Physical ( PCS) and mental component summary scores were also calculated. Follow-up was 5 years. Results Some 332 of 351 patients enrolled in the trial returned questionnaires. More than 70 per cent of questionnaires were returned at each time point. Both surgical interventions had a short-term negative effect on HRQoL and health status. This was less severe in the EVAR group than in the open repair group. In the longer term the physical domains of SF-36® favoured open repair: mean difference in PCS score between open repair and EVAR −1·98 (95 per cent c.i. −3·56 to −0·41). EQ-5D™ descriptive and EQ-5D™ visual analogue scale scores for open repair were also superior to those for EVAR after the initial 6-week interval: mean difference −0·06 (−0·10 to −0·02) and −4·09 (−6·91 to −1·27) respectively. Conclusion In this study EVAR appeared to be associated with less severe disruption to HRQoL and health status in the short term. However, during longer-term follow-up to 5 years, patients receiving open repair appeared to have improved quality of life and health status. [ABSTRACT FROM AUTHOR]

Abstract: Currently the transverse diameter is the primary decision criterion to assess rupture risk in patients with an abdominal aortic aneurysm (AAA). To obtain a measure for more patient-specific risk assessment, aneurysm wall stress, calculated using finite element analysis (FEA), has been evaluated in literature. In many cases, initial stress, present in the AAA wall during image acquisition, is not taken into account. In the current study the effect of initial stress incorporation (ISI) is determined by directly comparing wall displacements extracted from FEA and dynamic MRI. Ten patients with an aneurysm diameter were scanned with cardiac triggered MRI. Semi-automatic segmentation of the AAA was performed on the diastolic phase. The segmented in-slice contours were propagated through the remaining cardiac phases using an active contour model as to track wall displacements on MRI. Consequently, FEA with and without ISI (no-ISI) was performed using the diastolic geometry with simultaneously measured intra-aneurysm pressure values as boundary condition. Contours extracted from FEA were compared with MRI contours at corresponding cardiac phases by distance and relative area differences. The wall displacements from FEA with ISI show significant better correspondence with wall motion from MRI data in comparison with the no-ISI FEA (deviation in wall displacement 1.7% vs. 12.4%; ). Based on these results it can be concluded that incorporation of initial stress significantly improves wall displacement accuracy of FEA and therefore it should be incorporated in future analyses. [Copyright &y& Elsevier]

Abstract: Rupture risk estimation of abdominal aortic aneurysms (AAA) is currently based on the maximum diameter of the AAA. A more critical approach is based on AAA wall stress analysis. For that, in most cases, the AAA geometry is obtained from CT-data and treated as a stress free geometry. However, during CT imaging, the AAA is subjected to a time-averaged blood pressure and is therefore not stress free. The aim of this study is to evaluate the effect of neglecting these initial stresses (IS) on the patient-specific AAA wall stress as computed by finite element analysis. Additionally, the contribution of the nonlinear material behavior of the AAA wall is evaluated. Thirty patients with maximum AAA diameters below the current surgery criterion were scanned with contrast-enhanced CT and the AAA''s were segmented from the image data. The mean arterial blood pressure (MAP) was measured immediately after the CT-scan and used to compute the IS corresponding with the CT geometry and MAP. Comparisons were made between wall stress obtained with and without IS and with linear and nonlinear material properties. On average, AAA wall stresses as computed with IS were higher than without IS. This was also the case for the stresses computed with the nonlinear material model compared to the linear material model. However, omitting initial stress and material nonlinearity in AAA wall stress computations leads to different effects in the resulting wall stress for each AAA. Therefore, provided that other assumptions made are not predominant, IS cannot be discarded and a nonlinear material model should be used in future patient-specific AAA wall stress analyses. [Copyright &y& Elsevier]

Diagnosis of vascular disease and selection and planning of therapy are to a large extent based on the geometry of the diseased vessel. Treatment of a particular vascular disease is usually considered if the geometrical parameter that characterizes the severity of the disease, e.g. % vessel narrowing, exceeds a threshold. The thresholds that are used in clinical practice are based on epidemiological knowledge, which has been obtained by clinical studies including large numbers of patients. They may apply “on average”, but they can be sub-optimal for individual patients. To realize more patient-specific treatment decision criteria, more detailed knowledge may be required about the vascular hemodynamics, i.e. the blood flow and pressure in the diseased vessel and the biomechanical reaction of the vessel wall to this flow and pressure. Over the last decade, a substantial number of publications have appeared on hemodynamic modeling. Some studies have provided first evidence that this modeling may indeed be used to support therapeutic decisions. The goal of the research reported in this paper is to go one step further, namely to investigate the feasibility of a patient-specific hemodynamic modeling methodology that is not only effective (improves therapeutic decisions), but that is also efficient (easy to use, fast, as much as possible automatic) and robust (insensitive to variation in the quality of the input data, same outcome for different users). A review is presented of our research performed during the last 5 years and the results that were achieved. This research focused on the risk assessment for one particular disease, namely abdominal aortic aneurysm, a life-threatening dilatation of the abdominal aorta. [ABSTRACT FROM AUTHOR]

Background: Preoperative renal dysfunction is a significant risk factor for death after open abdominal aortic aneurysm repair. The aim of this study was to determine whether renal dysfunction also affected mortality after endovascular aneurysm repair. Methods: Patients from the EUROSTAR registry were stratified into two groups: 4198 with normal renal function (creatinine less than 133 µmol/ml) and 969 with renal dysfunction (serum creatinine more than 133 µmol/ml). Patient characteristics and postoperative complications in the two groups were compared and the effect of renal dysfunction on operative mortality was analysed by multivariable regression models. Results: Patients with renal dysfunction had significantly more co-morbidities, including cardiac and pulmonary impairment. Thirty-day mortality was significantly higher in the group with renal dysfunction (6·2 versus 2·0 per cent; P < 0·001). A significant increase in mortality (5·5 per cent) was also seen in patients with moderate renal dysfunction (serum creatinine 133-265 µmol/ml). After adjustment for age and other risk factors, renal dysfunction was still an independent risk factor for 30-day mortality (odds ratio 2·3, 95 per cent confidence interval 1·6 to 3·3; P < 0·001). Conclusion: Renal dysfunction was a significant and independent risk factor for death after endovascular aneurysm repair. Copyright © 2006 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

At present, the diameter of an abdominal aortic aneurysm (AAA) is considered to be the primary indicator of rupture risk. Surgical treatment is usually not considered before the diameter exceeds 5 cm, but rupture does occur for diameters less than 5 cm. We investigate if better rupture risk indicators can be obtained by patient-specific hemodynamic modeling. This paper discusses the steps involved in this modeling and describes our initial results for each of the steps. [Copyright &y& Elsevier]