Characterising the incidence and mode of visceral stent failure after fenestrated endovascular aneurysm repair (FEVAR).

BACKGROUND: In FEVAR, visceral stents provide continuity and maintain perfusion between the main body of the stent and the respective visceral artery. The aim of this study was to characterise the incidence and mode of visceral stent failure (type Ic endoleak, type IIIa endoleak, stenosis/kink, fracture, crush and occlusion) after FEVAR in a large cohort of patients at a high-volume centre. METHODS: A retrospective review of visceral stents placed during FEVAR over 15 years (February 2003-December 2018) was performed. Kaplan-Meier analyses of freedom from visceral stent-related complications were performed. The outcomes between graft configurations of varying complexity were compared, as were the outcomes of different stent types and different visceral vessels. RESULTS: Visceral stent complications occurred in 47/236 patients (19.9%) and 54/653 stents (8.3%). Median follow up was 3.7 years (IQR 1.7-5.3 years). There was no difference in visceral stent complication rate between renal, SMA and coeliac arteries. Visceral stent complications were more frequent in more complex grafts compared to less complex grafts. Visceral stent complications were more frequent in uncovered stents compared to covered stents. Visceral stent-related endoleaks (type Ic and type IIIa) occurred exclusively around renal artery stents. The most common modes of failure with SMA stents were kinking and fracture, whereas with coeliac artery stents it was external crush. CONCLUSION: Visceral stent complications after FEVAR are common and merit continued and close long-term surveillance. The mode of visceral stent failure varies across the vessels in which the stents are located.

Bypass surgery for chronic lower limb ischaemia.

BACKGROUND: Bypass surgery is one of the mainstay treatments for patients with critical lower limb ischaemia (CLI). This is the second update of the review first published in 2000. OBJECTIVES: To assess the effects of bypass surgery in patients with chronic lower limb ischaemia. SEARCH METHODS: For this update, the Cochrane Vascular Group searched its trials register (last searched October 2016) and the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library (last searched Issue 9, 2016). SELECTION CRITERIA: We selected randomised controlled trials of bypass surgery versus control or any other treatment. The primary outcome parameters were defined as early postoperative non-thrombotic complications, procedural mortality, clinical improvement, amputation, primary patency, and mortality within follow-up. DATA COLLECTION AND ANALYSIS: For the update, two review authors extracted data and assessed trial quality. We analysed data using odds ratio (OR) and 95% confidence intervals (CIs). We applied fixed-effect or random-effects models. MAIN RESULTS: We selected 11 trials reporting a total of 1486 participants. Six trials compared bypass surgery with percutaneous transluminal angioplasty (PTA), and one each with remote endarterectomy, thromboendarterectomy, thrombolysis, exercise, and spinal cord stimulation. The quality of the evidence for the most important outcomes of bypass surgery versus PTA was high except for clinical improvement and primary patency. We judged the quality of evidence for clinical improvement to be low, due to heterogeneity between the studies and the fact that this was a subjective outcome assessment and, therefore, at risk of detection bias. We judged the quality of evidence for primary patency to be moderate due heterogeneity between the studies. For the remaining comparisons, the evidence was limited. For several outcomes, the CIs were wide.Comparing bypass surgery with PTA revealed a possible increase in early postinterventional non-thrombotic complications (OR 1.29, 95% CI 0.96 to 1.73; six studies; 1015 participants) with bypass surgery, but bypass surgery was associated with higher technical success rates (OR 2.26, 95% CI 1.49 to 3.44; five studies; 913 participants). Analyses by different clinical severity of disease (intermittent claudication (IC) or CLI) revealed that peri-interventional complications occurred more frequently in participants with CLI undergoing bypass surgery than PTA (OR 1.57, 95% CI 1.09 to 2.24). No differences in periprocedural mortality were identified (OR 1.67, 95% CI 0.66 to 4.19; five studies; 913 participants). The primary patency rate at one year was higher after bypass surgery than after PTA (OR 1.94, 95% CI 1.20 to 3.14; four studies; 300 participants), but this difference was not shown at four years (OR 1.15, 95% CI 0.74 to 1.78; two studies; 363 participants). No differences in clinical improvement (OR 0.65, 95% CI 0.03 to 14.52; two studies; 154 participants), amputation rates (OR 1.24, 95% CI 0.82 to 1.87; five studies; 752 participants), reintervention rates (OR 0.76, 95% CI 0.42 to 1.37; three studies; 256 participants), or mortality within the follow-up period (OR 0.94, 95% CI 0.71 to 1.25; five studies; 961 participants) between surgical and endovascular treatment were identified. No differences in subjective outcome parameters, indicated by quality of life and physical and psychosocial well-being, were reported. The hospital stay for the index procedure was reported to be longer in participants undergoing bypass surgery than in those treated with PTA.In the single study (116 participants) comparing bypass surgery with remote endarterectomy of the superficial femoral artery, the frequency of early postinterventional non-thrombotic complications was similar in the treatment groups (OR 1.11, 95% CI 0.53 to 2.34). No mortality within 30 days of the index treatment or during stay in hospital in either group was recorded. No differences were identified in patency (OR 1.66, 95% CI 0.79 to 3.46), amputation (OR 1.70, 95% CI 0.27 to 10.58), and mortality rates within the follow-up period (OR 1.66, 95% CI 0.61 to 4.48). Information regarding clinical improvement was unavailable.No differences in major complications (OR 0.66, 95% CI 0.34 to 1.31) or mortality (OR 2.09, 95% CI 0.67 to 6.44) within 30 days of treatment between surgery and thrombolysis (one study, 237 participants) for chronic lower limb ischaemia were identified. The amputation rate was lower after bypass surgery (OR 0.10, 95% CI 0.01 to 0.80). No differences in late mortality were found (OR 1.56, 95% CI 0.71 to 3.44). No data regarding patency rates and clinical improvement were reported.Technical success resulting in blood flow restoration was higher after bypass surgery than thromboendarterectomy for aorto-iliac occlusive disease (one study, 43 participants) (OR 0.01, 95% CI 0 to 0.17). The periprocedural mortality (OR 0.33, 95% CI 0.01 to 8.65), follow-up mortality (OR 3.29, 95% CI 0.13 to 85.44), and amputation rates (OR 0.47, 95% CI 0.08 to 2.91) did not differ between treatments. Clinical improvement and patency rates were not reported.Comparing surgery and exercise (one study, 75 participants) did not identify differences in early postinterventional complications (OR 7.45, 95% CI 0.40 to 137.76) and mortality (OR 1.55, 95% CI 0.06 to 39.31). The remaining primary outcomes were not reported. There was no difference in maximal walking time between exercise and surgery (1.66 min, 95% CI -1.23 to 4.55).Regarding comparisons of bypass surgery with spinal cord stimulation for CLI, there was no difference in amputation rates after 12 months of follow-up (OR 4.00, 95% CI 0.25 to 63.95; one study, 12 participants). The remaining primary outcome parameters were not reported. AUTHORS' CONCLUSIONS: There is limited high quality evidence for the effectiveness of bypass surgery compared with other treatments; no studies compared bypass to optimal medical treatment. Our analysis has shown that PTA is associated with decreased peri-interventional complications in participants treated for CLI and shorter hospital stay compared with bypass surgery. Surgical treatment seems to confer improved patency rates up to one year. Endovascular treatment may be advisable in patients with significant comorbidity, rendering them high risk surgical candidates. No solid conclusions can be drawn regarding comparisons of bypass surgery with other treatments because of the paucity of available evidence. Further large trials evaluating the impact of anatomical location and extent of disease and clinical severity are required.

Causes of successful medico-legal claims following amputation.

INTRODUCTION: The causes of successful medico-legal claims following amputation were reviewed. METHODS: A retrospective analysis of claims handled by the National Health Service Litigation Authority, from 2005 to August 2010, was performed. Under the Freedom of Information Act, the National Health Service Litigation Authority provided limited details on closed claims, settled with damages, following a search of their database with the term "amputation." No demographic data were provided. RESULTS: During this period, 174 claims were settled by the National Health Service Litigation Authority, who paid out more than £36.3 million. The causes of the claims were the need for a lower limb amputation due to a delay in the diagnosis and or treatment of arterial ischaemia (56), an iatrogenic injury (15), the development of preventable pressure sores (15), the delay and or failure to diagnose a limb malignancy (6) and the delay in the management of an infected pseudo-aneurysm (1). Complications following orthopaedic surgery resulted in 25 successful claims as did the delayed diagnosis or mismanagement of 10 lower limb fractures. Additional claims followed the amputation of the wrong toe (1), a retained foreign body (2), an unnecessary amputation (4), inadequate consent (4), failure to provide thrombo-prophylaxis following amputation resulting in death (2) and a diathermy burn injury during an amputation (1). Delay in the diagnosis of and/or failure to manage an injury or infection resulted in 21 upper limb amputations. There was insufficient information provided in the remaining 11 claims to determine how the claim related to an amputation procedure. The largest single payout for damages (£1.9 million) resulted from the failure to diagnose and treat a femoral artery injury following a road traffic accident leading to an eventual below knee amputation. CONCLUSION: Delays in the diagnosis and or treatment of arterial ischaemia were the commonest reasons for a settled claim. Lessons can be learnt from potentially preventable cases that can be incorporated in medical education and training programs with the aim of reducing both amputation rates and litigation costs.

Combination antiplatelet therapy in patients with peripheral vascular bypass grafts.

Peripheral bypass graft occlusion occurs in approximately 25% of cases in the 5 years following surgery; hence, therapies directed at reducing the tendency toward thrombotic occlusion are of clinical importance. This trial was conducted to determine if the addition of clopidogrel to aspirin enhances antiplatelet therapy in patients with infrainguinal bypass grafts. A randomized placebo-controlled study was performed on 20 patients over 3 months following infrainguinal bypass surgery. In addition to their regular aspirin therapy, patients were randomized to receive either clopidogrel (group 1) or placebo (group 2) for 1 week. Platelet activation was measured ex vivo by platelet aggregometry and flow cytometry. In group 1, there was a significant reduction in spontaneous (SP), adenosine diphosphate (ADP), and arachidonic acid (AA)-induced platelet aggregation compared with group 2; SP -17% (CI -33, -0.2 p = 0.048), ADP -39%, (CI -56, -22 p = 0.001), AA -21% (CI -39, -4 p = 0.023). Flow cytometry demonstrated a significant reduction in ADP-induced platelet P-selectin expression and GPIIb/IIIa activation following treatment with clopidogrel but not with placebo. This study demonstrated that the addition of clopidogrel to aspirin reduces platelet activation measured by platelet aggregation and flow cytometry, supporting a long-term trial with clinical endpoints.