Transrenal Endovascular Aneurysm Repair-A Novel Approach for Abdominal Aortic Aneurysms with Difficult Neck Anatomy.

BACKGROUND: The endovascular approach to treating ruptured or symptomatic abdominal aortic aneurysms (AAAs) with difficult neck anatomy still poses a major challenge. This study proposes and evaluates the outcomes of a novel technique, Transrenal Endovascular Aneurysm Repair (Tr-EVAR) which utilizes the top ring 'valley' and 'peak' configuration of the Anaconda stent graft to achieve proximal seal in AAAs with an unfavourable neck. METHODS: All patients treated with Tr-EVAR over a period of 10 years were identified retrospectively. Demographic, clinical and outcome data were collected, and survival analysis was performed. The time-to-event was analyzed using Kaplan-Meier curves for complication-free survival, reintervention-free survival, and overall survival. RESULTS: During the study period, 36 patients ruptured, symptomatic or large AAAs having unfavorable necks and not fit for open repair underwent Tr-EVAR. Two patients died in the first 30 days postprocedure (5.6%). The overall survival at 1 year, 3 years and 5 years were 86%, 72% and 54% respectively with a mean overall survival of 74.0 months (SE 7.8, 95% confidence interval 58.7-89.3) which was comparable to chimney endovascular aneurysm repair (EVAR). The complication-free survival and reintervention-free survival at 1 year, 3 years, and 5 years were 75%, 61%, 42%, 78%, 64%, and 45%, respectively. CONCLUSIONS: Tr-EVAR can be considered as an off-the-shelf solution for urgent cases not fit for open repair with unfavourable neck features for standard EVAR. Careful patient selection and planning have generated acceptable immediate, midterm and long-term results comparable to those presented by chimney EVAR in the literature.

Mycotic Abdominal Aortic Aneurysms - A Tertiary Centre Experience and Formulation of a Management Protocol.

BACKGROUND: Mycotic abdominal aorta aneurysm (MAAA) is a rare and life-threatening condition. Because of its rarity, there is a lack of adequately powered studies and consensus on its treatment and follow up. This study aimed to review the outcomes following surgical intervention for MAAA in a single tertiary centre and to formulate a management protocol based on available evidence and expert opinion. MATERIALS AND METHODS: Data were collected by retrospective review of case records of all patients who underwent repair of MAAA in a single tertiary referral centre from 2001 to 2018. Demographic, clinical and outcome data were analysed and compared with previously published series in the literature. A management protocol was formulated based on available literature which was then reviewed and modified as per expert opinion from multidisciplinary discussions. RESULTS: Seventeen patients underwent repair of MAAA during the study period including 4 Open repairs, 4 surgeon modified fenestrated endovascular aortic aneurysm repairs (SM FEVAR) and 9 endovascular aortic aneurysm repairs (EVAR). One-year overall survival was 94.1%, 3-year survival was 81.8% and 5-year survival was 75.0%. The infection-free survival at 1, 3, and 5 years was 87.5%, 81.8% and 62.5%, respectively. The overall survival and infection-free survival curves for Open repair, EVAR and SM FEVAR when compared using Log Rank (Mantel-Cox) test and did not show any statistically significant difference. CONCLUSIONS: Management of MAAA with selective use of open or endovascular repair, in combination with appropriate long-term antibiotic therapy, can achieve acceptable outcomes. The proposed protocol can aid as a guiding document for the management of MAAA but needs taking into consideration individual patient variability and local expertise.

A comparison between one-stage and two-stage procedures for the creation of brachiobasilic arteriovenous fistulas.

INTRODUCTION: Vascular access is essential to end-stage renal failure patients requiring haemodialysis. Many patients require multiple fistula formation attempts in order to gain good access, making secondary and tertiary fistula options vital. Brachiobasilic fistulas are well established, but there is little evidence to compare the different surgical techniques in creating them. This study aimed to determine the patency and complication rates associated with these procedures. METHODS: Retrospective data was collected by reviewing case notes to determine fistula survival time and surgical setting. Patency, complications and required interventions were recorded for each group at three time intervals. The Kaplan-Meier method was used to calculate survival for each cohort. RESULTS: 37 brachiobasilic arteriovenous fistulas were created in 35 patients. 17 fistulas were one-stage procedures; 20 fistulas were made in two stages. Survival proportions were measured as 70.6%, 58.8% and 51.5% for the one-stage procedure and 95%, 90% and 78% for the two-stage procedure at 1 month, 1 year and 2 years respectively with p = 0.0385. DISCUSSION: Native brachiobasilic fistulas have advantages over prosthetic grafts. There are technical aspects which make the two-staged procedure preferable, including being more amenable to a day case surgery setting. Despite this, there is a lack of relative outcome differences in the literature, thus necessitating further work. CONCLUSION: Our data suggests creation of brachiobasilic fistulas using a two-staged procedure may result in improved patency rates. Complication rates were found to be statistically equivocal, with fistuloplasties and embolectomy shown to be effective in fistula salvage.

Arteriovenous fistula formations: key to vascular surgical training.

PURPOSE: To highlight missed training opportunities in daycase surgery for trainees to acquire competency in vascular anastomosis by performing arteriovenous fistula (AVF) formations. METHODS: Operative Room Management Information System records were reviewed for AVF procedures in daycase and general theatres at a UK Foundation Trust between 2007 and 2012. Data collected included procedure, procedure time (PT), patient length of stay (LOS), readmissions within 30 days of procedure and lead and assistant surgeons involved. RESULTS: Of 199 daycase AVF procedures reviewed, 59.3% (n=118) were brachiocephalic formations and 34.2% (n=68) radiocephalic formations. Trainees attended 41.2% of daycase AVF procedures and were lead surgeon in 7.3% of these. Mean PT was 64 minutes for consultants compared with 56 minutes for trainees, with no significant difference (p=0.297). Median patient LOS was less than 24 hours for both groups. Six daycase AVF procedures resulted in patient readmission within 30 days; five of these were operated on by consultants and one by a staff grade. During the same period, 258 AVF procedures were performed in general theatres. Trainees attended 64.3% of AVF formations performed in general theatres and were lead surgeon in 5.8% of these. CONCLUSIONS: Trainees attended and led few daycase AVF formations despite no significant difference in PT, patient LOS or readmission rate between consultant-led and trainee-led cases. Trainees attended more AVF formations performed in general theatres than daycase. However, trainees led a greater proportion of daycase AVF formations, possibly due to a less complex case mix that is more suitable for training.

Paradoxical neutrophil elastase release in endovascular abdominal aortic aneurysm repair.

Endovascular repair of abdominal aortic aneurysm potentially avoids problems associated with prolonged aortic cross-clamping that occurs with open repair, but it appears to have its own biologic consequences, which may relate to neutrophil elastase release. Blood samples of consecutive patients undergoing open or endovascular abdominal aneurysm repair were analyzed for neutrophil elastase/alpha(1)-antitrypsin complex and free elastase. Free elastase rose from baseline and fell quickly in open repair patients, returning to baseline by 144 hours. In the endovascular repair group, it continued to increase for up to 144 hours. Bound elastase increased to 24 hours, returning to baseline in endovascular repair patients by 72 hours, but remaining elevated in open repair patients at 144 hours. Open repair patients showed raised elastase/alpha(1)-antitrypsin complex and initial raised free elastase levels. High free elastase levels in endovascular repair patients may reflect less bound elastase and may paradoxically lead to a prolonged inflammatory postoperative response.