Early Elective Conversion for Failing Evar

Systematic review and meta-analysis of incidence, indications, and outcomes of early open conversions after EVAR for abdominal aortic aneurysms

INTRODUCTION

The purpose of this study is to report incidence, indications, and outcomes of early open conversions (EOC) after endovascular aortic repair (EVAR), defined as surgical conversion performed within 30 days from the initial EVAR.

EVIDENCE AQUISITION

A systematic review of the literature was performed (database searched: PubMed, Web of Science, Scopus, Cochrane Library; last search April 2023). Articles reporting EOC after EVAR comprising at least five patients were included. Meta-analyses of proportions were performed using a random-effects model.

EVIDENCE SYNTHESIS

Seventeen non-randomized studies, published between 1999 and 2022, were included. A total of 35,970 patients had previously undergone EVAR, of these 438 patients underwent EOC. Estimated incidence of EOC was 1.4% (95% CI 1.1-1.4; I2=81.66%). Specifically, in the works published before 2010 the incidence was 1.8% (95% CI 1.3-2.4; I2=74.25) while for subsequent ones it was 0.9% (95% CI 0.6-1.1; I2=69.82). Weighted mean age was 74.91 years (95% CI 72.42-77.39; I2=83.11%). Estimated rate of cause determining EOC were: access issue in 27.7% of patients (95% CI 13.8-41.6; I2=88.14%), incorrect placement of the endograft in 20.1% (95% CI 10.2-30.0; I2=76,9%), problems with "delivery system" in 9.0% (95% CI 4.9-13.1; I2=0%), aorto-iliac rupture in 8.6% (95% CI 4.5-12.6; I2=0%), endoprosthesis migration in 7.9% of cases (95% CI 3.3-12.4; I2=22.96%), failure in engaging the contralateral gate in 4.8% (95% CI 1.6-8; I2=0%), "kinking" or "twisting" of endoprosthesis in 3.3% (95% CI 0.6-5.9; I2=0%), graft thrombosis in 3.2% (95% CI 0.6-5.7; I2=0%), type Ia endoleak in 2.9% (95% CI 0.4-5.4; I2=0%), type III endoleak in 2.8% (95% CI 0.3-5.3; I2=0%) and endograft infection in 2.7% (95% CI 0.3-5.2; I2=0%). Intraoperative conversion rate was 91.1% (95% CI 85.8-96.4; I2=66.01%). Early mortality rate after EOC was 14.5% (95% CI 9.1-19.9; I2=48.31%). Mean length of stay (LOS) was 11.94 days (95% CI 6.718-17.172; I2=92.34%).

CONCLUSIONS

The incidence of EOC seems to decrease over time. Causes of EOC were mainly related to access problems and incorrect positioning of the endograft. Most of the EOC were performed intraoperatively carrying a high mortality rate.

[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.

Ten-Year Outcomes after Endovascular Aneurysm Repair (Evar) and Magnitude of Additional Procedures

Background and Aims:

With any new technology complications are possible, and problems with first-generation aortic stentgrafts have been extensively reported. The long-term outcome of this patient population and the magnitude of additional secondary procedures are, however, less well covered.

Materials and Methods:

Between February 1997 and November 1999, 48 patients (44 men and 4 women; mean age 70 years; range 54–85) with AAA (average 57mm, range 40–90mm) were treated with a Vanguard® endoprosthesis. Stentgrafts were sized by CT and angiography-based measurements. Results were continuously assessed using contrast-enhanced CT before discharge, 1, 3, 6 and 12 months after the procedure and thereafter annually. Since 2001 plain abdominal X-rays have been performed annually.

Results:

The technical implant success rate was 100%. Median follow-up was 91 months (range 7.6–120 months). None of the patients was lost during this period. Hospital mortality was 0%. There were 25 subsequent deaths (52%), the most common cause being coronary artery disease. There were ten late conversions to open surgical repair, including three emergency operations: two due to rupture and one to thrombosis. EVAR-related complications were encountered in 43 patients (90%): 12 primary endoleaks (all type II), 36 late endoleaks (16 type I, 2 type II and 18 type III), 22 migrations, 25 row separations, 20 thromboses, one endotension and 3 ruptures of the AAA. Secondary procedures were required in 39 patients (81%): 1 re-endografting by aortoiliac bifurcated graft and 3 with a uni-iliac graft; 33 limb graft repairs were performed and 19 infrarenal cuffs were placed. There were 4 late embolizations and 4 attempts, and 6 thrombolyses, four of which were successful. Further, 9 femoro-femoral crossover by-pass and 2 axillo-femoral by-pass operations and 2 amputations were carried out during the follow-up. Only one patient was alive without complications.

Conclusions:

The impact of long-term follow-up of patients treated with the new technology was emphasized in this patient population. A careful surveillance protocol and active endovascular treatment of complications can yield acceptable results and low AAA rupture and aneurysm mortality rates, also with the first-generation endovascular graft. A new technology, however, may involve unpredictable problems which can magnify the workload and incur high costs over several years after the initial procedure.

How To Diagnose and Manage Infected Endografts after Endovascular Aneurysm Repair

The prevalence of endograft infections (EI) after endovascular abdominal aortic aneurysm repair is below 1%. With the growing number of patients with aortic endografts and the aging population, the number of patients with EI might also increase. The diagnosis is based on an association of clinical symptoms, imaging, and microbial cultures. Angio-computed tomography is currently the gold-standard technique for diagnosis. Low-grade infection sometimes requires nuclear medicine imaging to make a correct diagnosis. There is no good evidence to guide management so far. In the case of active gastrointestinal bleeding, pseudoaneurysm, or extensive perigraft purulence involving adjacent organs, an invasive treatment should always be attempted. In the other cases (the majority), when there is not an immediate danger to the patient's life, a conservative management is started with a proper antimicrobial therapy. Any infectious cavity can be percutaneously drained. Management depends on the patient's condition and a tailored approach should always be offered. In the case of a patient who is young, has a good life expectancy, or in whom there is absence of significant comorbidities, a surgical attempt can be proposed. Surgical techniques favor, in terms of mortality, patency, and reinfection rate, the in situ reconstruction. Choice of technique relies on the center and the operator's experience. Long-term antibiotic therapy is always required in all cases, with close monitoring of the C-reactive protein.

Secondary Endovascular and Conversion Procedures for Failed Endovascular Abdominal Aortic Aneurysm Repair: Can We Still Be Optimistic?

The purpose of this study was to evaluate the incidence, etiology, and outcome of secondary endovascular and “open” conversion procedures after failed endovascular abdominal aortic aneurysm repair (EVAR). From January 1997 until December 2005, 625 patients with an infrarenal abdominal aortic aneurysm were treated by elective EVAR, with 98.7% ( n = 617) primary EVAR success. The mean follow-up of the 617 patients was 46.7 ± 11.2 months. One hundred of these patients (16.2%) required secondary endovascular or peripheral procedures, and 39 (6.3%) patients underwent a secondary abdominal conversion. There were 5 acute conversions (0.8%) and 34 elective conversions (5.5%). The pre-EVAR anatomic suitability data, the main cause of the secondary procedure, and stent graft type were compared between patients with primary EVAR success, patients in need of a secondary endovascular or peripheral procedure, and patients with abdominal conversion. The overall main causes for reinterventions were proximal migration ( n = 60; 9.7%), progressive kinking of the stent graft ( n = 59; 9.6%), and late type III endoleak ( n = 12; 1.9%). Multivariate logistic regression analysis showed that factors significantly correlated with secondary procedures were the abdominal aortic aneurysm's maximum diameter, the proximal neck's width and length, and particularly the commercial withdrawal of the stent graft ( p < .001). The morbidity and mortality rates of secondary endovascular or peripheral interventions were 0%. The mortality rate of acute secondary conversions was 20% ( n = 1) and of elective secondary conversions was 8.8% ( n = 3). The morbidity rates for acute and elective conversions were 0% and 65%, respectively. The aneurysm-related mortality rate in our series was below 1%. Abdominal conversion surgery still carries a high mortality rate, but the overall EVAR-related mortality rate remains low. Early pitfall detection and proper reintervention are crucial to long-term EVAR success.

Lost to follow-up: a potential under-appreciated limitation of endovascular aneurysm repair

OBJECTIVE

It has long been evident that lifetime follow-up after endovascular aneurysm repair (EVAR) is necessary to identify late complications. The purpose of this study is to test the hypothesis that late follow-up rates for EVAR in routine practice are inferior to those reported from protocol-driven clinical trials, consequently contributing to avoidable events associated with poor long-term outcome.

METHODS

From February 1999 to December 2005, 302 EVARs were performed and eligible for follow-up. Of these, 47 were performed as part of an industry-sponsored clinical trial (study patients). Responsibility for follow-up was assigned to a research nurse for study patients and to office clerical staff for nonstudy patients. Follow-up compliance was classified as either frequent (<1 missed scheduled appointment) or incomplete (>2 missed scheduled appointments). Overall survival and complication rates were analyzed.

RESULTS

Of the 302 patients, 203 (67.2%) had frequent follow-up and 99 (32.8%) had incomplete follow-up. The mean follow-up was significantly better in the frequent follow-up group (34.7 +/- 22 months) vs the incomplete follow-up group (18.8 +/- 18.6 months, P < .001). The 5-year survival (63.9% frequent vs 64.0% incomplete), the 5-year reintervention rate (22.3% frequent vs 10.8% incomplete), and incidence of known endoleak (14.8% frequent vs 9.1% incomplete) were statistically similar in the two groups. The incidence of major adverse events, defined as events requiring urgent surgical intervention, was significantly increased in the incomplete follow-up group (6.1% vs 0.5%; P = .006), with nearly half of these patients dying perioperatively. There was no difference in measured outcomes for study patients compared with nonstudy patients. However, mean follow-up was significantly longer for study patients vs nonstudy patients (44.8 +/- 23.7 months vs 26.8 +/- 20.9 months; P < .001).

CONCLUSIONS

Follow-up surveillance after EVAR is less intense in practice environments outside of clinical trials. Patients with incomplete follow-up have higher fatal complication rates than patients with frequent follow-up. These data expose a potential under-appreciated limitation of EVAR, questioning whether the findings in clinical trials defining the efficacy of EVAR can be routinely extrapolated to ordinary practice.