Risk factors for elective and urgent open conversion after EVAR-a retrospective observational study

Systematic Review and Meta-Analysis of Elective Open Conversion versus Fenestrated and Branched Endovascular Repair for Previous Non-Infected Failed Endovascular Aneurysm Repair

OBJECTIVE

To evaluate outcomes of patients electively undergoing fenestrated and branched endovascular repair (F/B-EVAR) or open conversion for failed previous non-infected endovascular aneurysm repair (EVAR).

DATA SOURCES

Embase, MEDLINE, Cochrane Library.

REVIEW METHOD

The protocol was prospectively registered on PROSPERO (CRD42023404091). The review followed the PRISMA guidelines; certainty was assessed through the GRADE and quality through MINORS tools. Outcomes data were pooled separately for F/B-EVAR and open conversion. A random effects meta-analysis of proportions was conducted; heterogeneity was assessed with the I2 statistic.

RESULTS

Thirty eight studies were included, for a total of 1 645 patients of whom 1 001 (60.9%) underwent an open conversion and 644 (39.1%) a F/B-EVAR. The quality of evidence was generally limited. GRADE certainty was judged low for 30 day death (in both groups) and F/B-EVAR technical success, and very low for the other outcomes. Pooled 30 day death was 2.3% (I2 33%) in the open conversion group and 2.4% (I2 0%) in the F/B-EVAR conversion group (p = .36). Technical success for F/B-EVAR was 94.1% (I2 23%). The pooled 30 day major systemic complications rate was higher in the open conversion (21.3%; I2 74%) than in the F/B-EVAR (15.7%; I2 78%) group (p = .52). At 18 months follow up, the pooled re-intervention rate was 4.5% (I2 58%) in the open conversion and 26% (I2 0%) in the F/B-EVAR group (p < .001), and overall survival was 92.5% (I2 59%) and 81.6% (I2 68%), respectively (p = .005).

CONCLUSION

In the elective setting, and excluding infections, the early results of both open conversion and F/B-EVAR after failed EVAR appear satisfactory. Although open conversion presented with higher complication rates in the first 30 days after surgery, at follow up it seemed to be associated with fewer re-interventions and better survival compared with F/B-EVAR.

[Late Open Semi-conversion with Endograft Preservation for (Type II) Endoleaks with Late Aneurysm Sac Enlargement after EVAR - Indications, Method and Results in Our Own Patient Collective]

EVAR (endovascular aortic repair) is the most common method for treating an abdominal aortic aneurysm, but according to the latest findings it carries the risk of subsequent complications. These can be caused by (late) aneurysm sac growth. If conservative and surgical therapies fail to treat the aneurysm sac growth, open conversion is necessary to prevent aneurysm rupture. There are several options for open conversion, in which the EVAR prosthesis can be completely preserved or is (partially) removed. Late open semi-conversion with complete in-situ preservation of the EVAR-prosthesis and gathering of the aneurysm sac are a less invasive method than complete conversion and may be performed instead for selected patients. The aim of the present work is to present the surgical method, including indications and technical information, as well as the presentation of the results in our recent patient collective.All patients semi-converted in our department of vascular surgery and phlebology due to (type II) endoleak were included. All data are presented as n (%) or median (range).Between 6/2019 and 3/2023, 13 patients underwent semi-conversion 6 (2-12) years (median, range) after the initial EVAR. The aneurysm sac diameter at the time of semi-conversion was 69 mm (58-95 mm), the operating time was 114 min (97-147 min), the blood loss was 100 ml (100-1500 ml). Five (38%) patients received blood transfusion intraoperatively and 2 (15%) postoperatively. The stay in the intensive care unit lasted 1 (1-5) days, the hospitalisation time was 8 (6-11) days. Postoperative complications were intestinal atony (3 [23%], 1 [8%] with nausea/emesis and gastric tube insertion), anaemia (2 [15%]), hyponatraemia (2 [15%]), delirium (1 [8%]), COVID-19 infection (1 [8%]) and 1 [8%] intra-abdominal postoperative bleeding with the indication for surgical revision and the transfusion of 8 erythrocyte concentrates.Semi-conversion is a safe and practicable surgical method with few severe complications for a selected group of patients, which should be considered as an alternative to more invasive methods with (partial) removal of the EVAR-prosthesis. Further long-term studies comparing semi-conversion to full conversion are needed to demonstrate its benefits.