Progressive Device Failure at Long Term Follow Up of the Nellix EndoVascular Aneurysm Sealing (EVAS) System.

OBJECTIVE: High rates of midterm failure of the Nellix EndoVascular Aneurysm Sealing (EVAS) System resulted in device withdrawal from the UK market. The study aim was to report long term Nellix EVAS outcomes and management of a failing device. METHODS: A retrospective review of EVAS procedures at a tertiary unit was performed. Device failure was defined as a triad of stent migration, stent separation, and secondary sac expansion, or any intervention for type 1 endoleak, device rupture, or explant. RESULTS: 161 (male n = 140, female n = 21) patients with a median follow up of 6.0 (IQR 5.0-6.6) years were included. Freedom from all cause mortality estimate at six years was 41.5%. There were 70 (43.5%) device failures with a freedom from device failure estimate at six years of 32.3%. Failure was the result of sac expansion (n = 41), caudal stent migration (n = 36), stent separation (n = 26), and secondary AAA rupture (n = 15). A substantial number of type 1 endoleaks was present (1a n = 33, 1b n = 11), but the type 2 endoleak rate was low at 3.7%. Some 36 (22.4%) patients required re-intervention. Twenty-one patients underwent explant with no 30 day deaths. Six patients underwent Nellix-in-Nellix application (NINA) with one early death from bowel ischaemia and one patient who died later from non-aneurysm related cause. Two NINA patients have ongoing sac expansion and two have had thrombosis of a Nellix limb or visceral stent. Proximal embolisation was only successful in one of six cases. CONCLUSION: The long term failure rate of Nellix EVAS is high. All patients with a device must be informed and be enrolled in enhanced surveillance. EVAS explant is an acceptable technique with favourable outcomes. Management by open explant, if the patient is fit, should be considered early and offered to those with device failure.

Erectile Dysfunction in Peripheral Vascular Disease: Endovascular Revascularization as a Potential Therapeutic Target.

INTRODUCTION: Erectile dysfunction (ED) affects more than 150 million men worldwide, with deleterious effects on quality of life. ED is known to be associated with ischemic heart disease but the impact of ED in patients with peripheral arterial disease (PAD) is unknown. We assessed the prevalence and severity of ED in patients with PVD. METHODS: Following ethical approval, sequential male patients diagnosed with PAD over a 1-year period following diagnosis of intermittent claudication. The patient demographics and comorbidities were recorded, with the International Index of Erectile Function (IIEF-5) questionnaire used to grade severity of ED. Computed tomographic angiography and severity of stenosis in the proximal vessels and internal pudendal arteries were correlated using a modified Bollinger Matrix scoring system. RESULTS: 60 patients were recruited, most (77.2%) reported erectile dysfunction (52.5% severe, 22.5% moderate). Patients with severe ED were more likely to have 2 or more comorbidities (P = .009). 86.7% with severe ED had bilateral internal pudendal artery stenosis with a mean modified Bollinger score of 17.6. 35.5% of moderate ED patients had bilateral internal pudendal stenosis with a mean Bollinger score of 11.75. There was significant difference in overall scores between moderate and severe erectile dysfunction (p< 0.05), thus indicating a potential link between ED severity and extent of vessel stenosis. CONCLUSION: There is a substantial burden of clinically significant ED among patients with PAD. This study suggests ED should be discussed with all PAD patients and ED may precede a PAD diagnosis. There is scope for endovascular revascularization as a treatment option for ED secondary to arterial insufficiency.

Post-operative arterio-venous fistula blood flow influences primary and secondary patency following access surgery.

PURPOSE: Primary arteriovenous fistula arterio venous fistula (AVF) formation has proven to be the best and optimal vascular access for the majority of haemodialysis patients. At present there are limited data to suggest which haemodynamic parameters most correlate with the likelihood of early failure. The aim of this study is to identify the haemodynamic predictors of early failure, hence identify which fistulae may benefit from timely pre-emptive intervention. MATERIAL AND METHODS: Retrospective analysis of data was performed of 201 patients undergoing native AVF creation over a one year period. Demographic details, co-morbidity, preoperative vessel calibre were collected. Flow was measured by duplex ultrasound post operatively. RESULTS: Preoperative vein calibre (p = 0.01) and fistula flow (p < 0.001) positively affected primary patency. Age, gender, ethnicity, type of fistula, hypertension and preoperative arterial calibre did not influence outcome. Regression analysis showed that the strength of correlation between early postoperative fistula flow and patency decreased progressively with time. Six week flow predicts early, but not late, failure. ROC analysis identified 300 ml/min flow as the best predictor of patency. Fistulae with flow above 300 ml/min were more likely to remain patent over the next 12 months (p < 0.001, HR = 7.4). CONCLUSION: Postoperative fistula flow of less than 300 ml/min identifies AVFs at high risk of early failure. These may be candidates for early intervention with balloon assisted maturation. The findings of this retrospective cohort study strongly support the need for a more robust prospectively designed trial identifying haemodynamic factors that can predict mid and long-term AVF patency.