A population-based study of post-endovascular aortic repair rupture during 15 years

Identifying barriers and facilitators to follow-up after endovascular aortic repair (EVAR): Qualitative study design and protocol

Endovascular aortic repair (EVAR) is now first line therapy for most patients with abdominal aortic aneurysms (AAA) as it reduces perioperative morbidity and mortality compared to open surgery. However, up to 40 % of patients do not undergo recommended follow-up, increasing risk of subsequent rupture. Risk factors for loss to follow-up have been studied retrospectively, however, qualitative studies assessing perceived barriers and facilitators to follow-up have not been performed and there are few qualitative protocols within the vascular surgery literature. This article presents a qualitative descriptive study protocol aimed at understanding and improving post-operative follow-up adherence after EVAR developed through an iterative process based on the Theoretical Domains Framework of behavior change. Steps include:•Selection of target behavior and study design•Development of study materials, sampling/recruitment strategy, and data collection•Qualitative data analysis and reporting findingsWe demonstrate the feasibility of this study by pilot testing of the semi-structured interview guides on a small group of patients, healthcare providers, and key personnel. This protocol aims to describe key stakeholder experiences within the healthcare system that will ultimately serve as the basis for future multi-institutional research piloting intervention strategies to improve EVAR follow-up.

Sealing Zone Failure Decreases the Long Term Durability of Endovascular Aneurysm Repair

OBJECTIVE

Endovascular aneurysm repair (EVAR) has a higher long term aneurysm related mortality rate compared with open surgery, mainly due to aneurysm rupture. Loss of stent graft to vessel apposition at the EVAR sealing zones is a potential cause of post-EVAR rupture. This study aimed to investigate sealing zone failure and its relationship with post-EVAR rupture.

METHODS

This was a retrospective structured review of pre- and post-operative computed tomography (CT) scans of 399 consecutive patients treated with standard bifurcated EVAR. The primary outcome was total loss of seal at last post-operative CT. Secondary outcomes were partial loss of seal, standard follow up detection, post-EVAR rupture, aneurysm sac development, and endoleaks.

RESULTS

During a median follow up of 5.3 years, total and partial loss of seal occurred in 85 (21.3%) and 78 (19.5%) patients, respectively. Initial mean sealing zone lengths were within current recommendations but decreased over time, mainly due to vessel dilatation. Mean proximal sealing length at the one month CT was 15.5 ± 10.5 mm (95% confidence interval [CI] 12.6 - 18.5 mm) in the group with total loss of seal, 14.3 ± 6.9 mm (95% CI 12.2 - 16.4 mm) with partial loss of seal, and 23.2 ± 7.4 mm (95% CI 22.3 - 24.0 mm) with preserved seal through follow up (p < .001). Mean iliac sealing lengths were 22.4 ± 12.1 mm (95% CI 18.9 - 25.8 mm) if total loss and 21.8 ± 10.0 mm (95% CI 19.6 - 24.0 mm) if partial loss of seal vs. 34.7 ± 12.4 mm (95% CI 33.8 - 35.7 mm) if preserved seal. Larger vessel diameters were associated with loss of seal in both the proximal and distal sealing zones. During the study period, 13 post-EVAR ruptures occurred, all preceded by CT findings of total (n = 7) or partial (n = 6) loss of seal. Aneurysm sac expansion was seen in 40% of patients with total loss of seal, 18% with partial loss of seal, and 6.6% with preserved seal.

CONCLUSION

Loss of seal after EVAR is frequent and associated with post-EVAR rupture. Increased recommended sealing zones lengths and focus on sealing zones in surveillance may reduce post-EVAR ruptures and aneurysm related death.

Friendly Neck Anatomy Does Not Prevent Neck-Related Adverse Events After EVAR

BACKGROUND

Life-long follow-up after endovascular aneurysm repair (EVAR) is costly and burdensome to the patient. Follow-up should be stratified based on the risk of EVAR failure. Aneurysm neck is thought to be the single most important risk factor. This study investigated neck anatomy as a predictor of neck-related adverse events after EVAR.

METHODS

This retrospective single-center study included consecutive patients undergoing elective EVAR for infrarenal abdominal aortic aneurysms between 2011 and 2016 (n = 222) who were followed with yearly imaging until December 2020. Hostile neck was defined as neck length ≤15 mm, width ≥28 mm, angulation ≥60°, calcification, or thrombus ≥50% of circumference or conical neck based on preoperative computed tomography angiography. Neck-related adverse event was defined as aneurysm rupture, any neck-related reintervention or type 1a endoleak during follow-up.

RESULTS

Ninety (41%) patients had hostile neck and 132 (59%) had friendly neck. There were no differences in 30-day mortality (1% vs. 1%, P = 0.78), major adverse events (20% vs. 16%, P = 0.43) or reinterventions during the hospital stay (8% vs. 4%, P = 0.20) between patients with hostile and friendly neck. Estimated survival at 1 year was 89 ± 3% for hostile neck and 95 ± 2% for friendly neck patients (P < 0.01). Five-year survival estimates were 51 ± 6% and 66 ± 4%, respectively. Aneurysm-related mortality was higher after 6 years in patients with hostile neck (P < 0.01). Twenty-four patients (11%) suffered neck-related adverse events with mean time-to-event of 3.3 ± 2.8 years; there were no differences between the groups stratified by neck anatomy. Incidentally, preoperative aneurysm diameter was found to be an independent risk factor for neck-related adverse events and aneurysm-related mortality; 53 patients (24%) had aneurysm diameter ≥70 mm, which was associated with nearly 4-fold risk of neck-related complications during the follow-up.

CONCLUSIONS

Friendly neck anatomy may not protect from neck-related adverse events after EVAR in the long-term. Especially patients with large aneurysms should be followed closely.

Open Conversion with Explantation of Stent Grafts After Endovascular Aneurysm Repair for Abdominal Aortic Aneurysm

BACKGROUND

Although endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA) is widely used worldwide, the fact that it is associated with increased rates of reintervention has been considered a problem. This study aimed to analyze the outcomes of primary open AAA repair and open conversion with explantation of stent grafts after EVAR.

METHODS

In this retrospective study, we enrolled 1,120 patients (open repair, n = 664; EVAR, n = 456) who underwent AAA repair at Kobe University from 1999 to 2019. Of the 664 patients who underwent open repair, 121 (patients who underwent primary open repair (POR) as a concomitant procedure and patients with ruptured AAA) were excluded from the study. The outcomes of POR were compared with those of open conversion with explantation of stent grafts.

RESULTS

Of the 543 patients who underwent open repair, 513 underwent POR and 30 underwent open conversion with explantation of stent grafts. The operation time for POR was significantly less than that for open conversion with explantation. During surgery, patients who underwent open conversion with explantation required significantly more transfusions of red cell concentrate, fresh frozen plasma, and platelet concentrate than those who underwent POR. Overall, 30 patients who underwent open conversion with explantation required a total of 48 reinterventions before surgery. Hospital mortality rates were 0.7% and 0% in the POR and open conversion with explantation groups, respectively (P = 0.62). Although overall survival at 5 years in the POR group was significantly better than that in the open conversion with explantation group (89.3 ± 1.7% vs. 79.5 ± 9.6%; P = 0.01), there were no significant differences between the 2 groups regarding the freedom from aortic event (hospital death, reintervention, and aortic death). According to the multivariate analysis, open conversion with explantation was not an independent risk factor for late death. There were 20 patients who were hesitant to undergo OCE, although we recommended OCE. In a subgroup analysis, the overall mean cost borne by patients who underwent EVAR was approximately 2.3 times higher compared with that borne by patients who underwent POR.

CONCLUSIONS

Although demanding, both early and long-term outcomes of OCE have been favorable in our present study. OCE is highly recommended in patients with persistent sac enlargement after EVAR.

A Greek Multicentre Study Assessing the Outcome of Late Rupture After Endovascular Abdominal Aortic Aneurysm Repair

OBJECTIVE

Late rupture after endovascular aortic aneurysm repair (EVAR) for an abdominal aortic aneurysm (AAA) is an increasing complication associated with a high mortality rate. This study aimed to analyse the causes and outcomes in patients with AAA rupture after EVAR.

METHODS

A multi-institutional Greek study of late ruptures after EVAR between 2008 - 2022 was performed. Primary outcomes were intra-operative and in hospital death.

RESULTS

A total of 70 patients presented with late rupture after EVAR (proportion of ruptured EVARs among all EVARs, 0.6%; 69 males; mean age 77.2 ± 6.7 years). The mean time interval between EVAR and late rupture was 72.3 months (range 6 - 180 months). In all cases the cause of rupture was the presence of an endoleak (type I, 73%) with sac enlargement. Moreover, 34% of subjects with rupture after EVAR had been lost to follow up and 32% underwent a secondary intervention. Additionally, 57 patients (81%) were treated by conversion to open surgical repair (COSR) and the remainder by endovascular correction of endoleak (ECE). Eleven intra-operative deaths (16%) were recorded. The overall in hospital mortality rate was 41% (23% ECE vs. 46% COSR; p = .21). Of the patients who presented as initially haemodynamically stable, 23% died during hospitalisation, while the respective mortality rate for patients who presented as unstable was 78% (odds ratio [OR] 11.8, 95% confidence interval [CI] 3.6 - 39.1; p < .001). Multivariable logistic regression analysis revealed that severity of haemodynamic shock was the most significant risk factor for intra-operative (OR 7.15, 95% CI 1.58 - 32.40; p = .010) and in hospital death (OR 9.53, 95% CI 2.79 - 32.58; p < .001).

CONCLUSION

These data underline the devastating prognosis of late rupture after EVAR. Haemodynamic status at presentation was an important predictive factor for death both in the ECE and COSR groups. Rigorous follow up and prompt evaluation of an unstable patient in case of rupture after EVAR is recommended.

Re-Rupture 2 Years after Endovascular Aortic Aneurysm Repair Rupture

Re-rupture 2 years after endovascular aortic aneurysm repair (EVAR) rupture is an extremely rare event and limited data exist in the literature. We present an interesting case of a patient with an abdominal aortic rupture that had undergone 2 years before an endovascular repair for rupture after EVAR due to a type IA endoleak. The patient underwent a successful embolization of the type IA endoleak. Onyx was used to seal the gutter between the aortic wall and the endograft and the 1-month post-embolization CT showed complete sealing with no contrast in the sac. Two years after the rupture, he was presented again with clinical signs of hemodynamic shock and instability. An urgent CT Angiograph showed again rupture due to a type IA endoleak. The patient underwent an emergency open laparotomy. We analyze the re-rupture after EVAR while taking data from the literature into account.

Mortality and risk factors for ruptured abdominal aortic aneurysm after repair endovascular (rARE)

Objective

The aim of this study was to characterize risk factors for infrarenal abdominal aortic aneurysm rupture after endovascular repair (rARE) and evaluate 30-day mortality in comparison to primary ruptured abdominal aortic aneurysm (rAAA).

Methods

A retrospective review of all adult patients with rAAA at a single tertiary university care center between February 11, 2006, and December 31, 2018, was performed. A total of 267 patients with rAAA were identified, 11 of whom had rARE. Descriptive statistics were applied due to the small sample size.

Results

Overall 30-day mortality was similar between primary rAAA and rARE (31.5% vs 27.3%); however, patients with rARE were more likely to receive palliative care (3.9% vs 18.2%). Mortality of patients who underwent operative intervention was 11.1% for rARE and 28.7% for primary rAAA at 30 days. All patients had an endoleak at the time of rupture. Type 1 and type 3 endoleaks resulting in direct aortic sac pressurization were the primary cause of rARE (9 of 11 patients); however, rupture occurred in two patients with only a type 2 endoleak. There was no sac expansion at the time of rupture in four of 11 patients with rARE. Four of 11 patients were lost to follow-up prior to rARE.

Conclusions

rARE is an uncommon complication following EVAR and contributes to late aneurysm-related mortality following endovascular repair. Although the 30-day mortality rate was similar for rARE and primary rAAA, larger series are required to determine which patients with rARE will benefit from intervention. The presence of endoleak and sac expansion may alert surgeons to increased risk of rARE; however, a subset of patients with rARE did not have sac expansion or surveillance imaging on follow-up. Loss to lifelong imaging surveillance remains a risk factor for rARE.

Biomechanics and Early Sac Regression after Endovascular Aneurysm Repair of Abdominal Aortic Aneurysm

Background

Sac regression after endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms (AAA) is regarded as a marker of successful response to treatment. Several factors influence sac behavior after EVAR, yet little is known about the value of preoperative biomechanics. The aim of this study was to investigate the difference in aortic biomechanics between patients with and without sac regression.

Methods

Patients treated with standard EVAR for infrarenal AAA at the Karolinska University Hospital between 2009 and 2012 with one preoperative and a minimum of two postoperative computed tomography angiography (CTA) scans were considered for inclusion in this single-center retrospective cohort study. Biomechanical indices such as AAA wall stress and wall stress-strength ratio as well as intraluminal thrombus (ILT) thickness and stress were measured preoperatively in A4ClinicRE (VASCOPS GmbH). AAA diameter and volume were analyzed on preoperative, 30-day, and 1-year CTAs. Patients were dichotomized based on sac regression, defined as a ≥ 5 mm decrease in maximal AAA diameter between the first two postoperative CTA scans. Multivariable logistic regression was used for analysis of factors associated with early sac regression.

Results

Of the 101 patients treated during the inclusion period, 64 were included. Thirty-nine (61%) demonstrated sac regression and 25 (39%) had a stable sac or sac increase. The mean patients age (73 years vs 76 years), male sex (85% vs 96%), and median AAA diameter (58 mm vs 58.5 mm) did not differ between patients with and without sac regression. Although no difference in preoperative biomechanics was seen between the groups, multivariable logistic regression revealed that a larger AAA diameter (odds ratio [OR], 1.27; 95% confidence interval [CI], 1.06-1.51; P = .009) and smoking (OR, 22.1; 95% CI, 2.78-174; P = .003) were positively associated with sac regression. In contrast, the lumen diameter (OR, 0.87; 95% CI, 0.77-0.98; P = .023), ILT thickness (OR, 0.85; 95% CI, 0.75-0.97; P = .013), aspirin or direct-acting oral anticoagulant use (OR, 0.11; 95% CI, 0.02-0.61; P = .012), and mean ILT stress (OR, 0.35; 95% CI, 0.14-0.87; P = .024) showed a negative association. Patients with sac regression had fewer reinterventions (log-rank P = .010) and lower mortality (log-rank P = .012) at the 5-year follow-up.

Conclusions

This study, characterizing preoperative biomechanics in patients with and without sac regression, demonstrated a negative association between mean ILT stress and ILT thickness with a change in sac diameter after EVAR. Given that the ILT is a highly dynamic entity, further studies focusing on the role of the thrombus are needed. Furthermore, patients presenting with early sac regression had improved outcomes after EVAR.

Clinical presentation, operative management, and long-term outcomes of rupture after previous abdominal aortic aneurysm repair

OBJECTIVE

The aim of the present study was to evaluate the presentation trends, intervention, and survival of patients who had been treated for late abdominal aortic aneurysm rupture (LAR) after open repair (OR) or endovascular aortic aneurysm repair (EVAR).

METHODS

We reviewed the clinical data from a single-center, retrospective database for patients treated for LAR from 2000 to 2020. The end points were the 30-day mortality, major postoperative complication, and survival. The outcomes between LAR managed with EVAR (group I) vs OR were compared (group II).

RESULTS

Of 390 patients with infrarenal aortic rupture, 40 (10%) had experienced aortic rupture after prior aortic repair and comprised the LAR cohort (34 men; age 78 ± 8 years). LAR had occurred before EVAR in 30 and before OR in 10 patients. LAR was more common in the second half of the study with 32 patients after 2010. LAR after prior OR was secondary to ruptured para-anastomotic pseudoaneurysms. After initial EVAR, LAR had occurred despite reintervention in 17 patients (42%). The time to LAR was shorter after prior EVAR than after OR (6 ± 4 vs 12 ± 4 years, respectively; P = .003). Treatment for LAR was EVAR for 25 patients (63%; group I) and OR for 15 (37%, group II). LAR after initial OR was managed with endovascular salvage for 8 of 10 patients. Endovascular management was more frequent in the latter half of the study period. In group I, fenestrated repair had been used for seven patients (28%). Salvage for the remaining cases was feasible with EVAR, aortic cuffs, or limb extensions. The incidence of free rupture, time to treatment, 30-day mortality (8% vs 13%; P = .3), complications (32% vs 60%; P = .1), and disposition were similar between the two groups. Those in group I had had less blood loss (660 vs 3000 mL; P < .001) and less need for dialysis (0% vs 33%; P < .001) than those in group II. The median follow-up was 21 months (interquartile range, 6-45 months). The overall 1-, 3-, and 5-year survival was 76%, 52%, and 41%, respectively, and was similar between groups (28 vs 22 months; P = .48). Late mortality was not related to the aorta.

CONCLUSIONS

LAR after abdominal aortic aneurysm repair has been encountered more frequently in clinical practice, likely driven by the frequency of EVAR. However, most LARs, including those after previous OR, can now be salvaged with endovascular techniques with lower morbidity and mortality.

Editor's Choice - Structured Computed Tomography Analysis can Identify the Majority of Patients at Risk of Post-Endovascular Aortic Repair Rupture

OBJECTIVE

The main objective was to report mechanisms and precursors for post-endovascular aneurysm repair (EVAR) rupture. The second was to apply a structured protocol to explore whether these factors were identifiable on follow up computed tomography (CT) prior to rupture. The third objective was to study the incidence, treatment, and outcome of post-EVAR rupture.

METHODS

This was a multicentre, retrospective study of patients treated with standard EVAR at five Swedish hospitals from 2008 to 2018. Patients were identified from the Swedvasc registry. Medical records were reviewed up to 2020. Index EVAR and follow up data were recorded. The primary endpoint was post-EVAR rupture. CT at follow up and at post-EVAR rupture were studied, using a structured protocol, to determine rupture mechanisms and identifiable precursors.

RESULTS

In 1 805 patients treated by EVAR, 45 post-EVAR ruptures occurred in 43 patients. The cumulative incidence was 2.5% over a mean follow up of 5.2 years. The incidence rate was 4.5/1 000 person years. Median time to post-EVAR rupture was 4.1 years. A further six cases of post-EVAR rupture in five patients found outside the main cohort were included in the analysis of rupture mechanisms only. The rupture mechanism was type IA in 20 of 51 cases (39%), IB in 20 of 51 (39%) and IIIA/B in 11 of 51 (22%). One of these had type IA + IB combined. One patient had an aortoduodenal fistula without another mechanism being identified. Precursors had been noted on CT follow up prior to post-EVAR rupture in 16 of 51 (31%). Retrospectively, using the structured protocol, precursors could be identified in 43 of 51 (84%). In 17 of 27 (63%) cases missed on follow up but retrospectively identifiable, the mechanisms were type IB/III. Overall, the 30 day mortality rate after post-EVAR rupture was 47% (n = 24/51) and the post-operative mortality rate was 21% (n = 7/33).

CONCLUSIONS

Most precursors of post-EVAR rupture are underdiagnosed but identifiable before rupture using a structured follow up CT protocol. Precursors of type IB and III failures caused the majority of post-EVAR ruptures.

Effects of antithrombotic therapy on abdominal aortic aneurysm sac size after endovascular repair in patients with favorable neck anatomy

PURPOSE

To evaluate the influence of antiplatelet or anticoagulant therapy on sac behavior after endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA) MATERIALS AND METHODS: This study retrospectively analyzed data from patients with favorable neck anatomy who underwent EVAR between 2007 and 2019. Patients with ruptured AAA and ≤1 year of sac behavior evaluation were excluded. Sac shrinkage after 1 year, persistent type II endoleak, and late sac expansion were examined.

RESULTS

In total, 182 patients with favorable neck anatomy were included in this study. Multivariable analysis identified occluded inferior mesenteric artery (IMA [P = .049]), presence of posterior thrombus (P = .009) and no antiplatelet therapy (P = .012) as factors positively associated with sac shrinkage at 1 year. Persistent type II endoleak was detected in 56 (30.8%) patients, with patent IMA (P = .006), lack of posterior thrombus (P = .004), number of patent lumbar arteries (P = .004), and antiplatelet therapy (P = .039) being identified as significant risk factors. Multivariable analysis identified larger initial AAA diameter (P < .001), lack of posterior thrombus (P = .038), and antiplatelet (P = .038) and anticoagulation therapies (P = .003) as risk factors for late sac expansion.

CONCLUSIONS

After EVAR in patients with favorable neck anatomy, antiplatelet therapy is associated with lack of sac regression at 1 year, whereas antiplatelet and anticoagulant therapies are risk factors for late sac expansion.