Salvage of failed prior endovascular abdominal aortic aneurysm repair with fenestrated endovascular stent grafts

Reinterventions and sac dynamics after fenestrated endovascular aortic repair with physician-modified endografts for index aneurysm repair and following proximal failure of prior endovascular aortic repair

OBJECTIVE

The high frequency of reinterventions after fenestrated endovascular aortic repair (FEVAR) with physician-modified endografts (PMEGs) has been well-studied. However, the impact of prior EVAR on reinterventions and sac behavior following these procedures remains unknown. We analyzed 3-year rates of reinterventions and sac dynamics following PMEG for index aneurysm repair compared with PMEG for prior EVAR with loss of proximal seal.

METHODS

We performed a retrospective analysis of 122 consecutive FEVARs with PMEGs at a tertiary care center submitted to the United States Food and Drug Administration in support of an investigational device exemption trial. We excluded patients with aortic dissection (n = 5), type I to III thoracoabdominal aneurysms (n = 13), non-elective procedures (n = 4), and prior aortic surgery other than EVAR (n = 8), for a final cohort of 92 patients. Patients were divided into those who underwent PMEG for index aneurysm repair (primary FEVAR) and those who underwent PMEG for rescue of prior EVAR with loss of proximal seal (secondary FEVAR). The primary outcomes were freedom from reintervention and sac dynamics (regression as ≥5 mm decrease, expansion as ≥5 mm increase, and stability as <5 mm increase or decrease) at 3 years. Secondary outcomes were perioperative mortality and 3-year survival.

RESULTS

Of the 92 patients included, 56 (61%) underwent primary FEVAR and 36 (39%) underwent secondary FEVAR. Secondary FEVAR patients were older (78 years [interquartile range (IQR), 74.5-83.5 years] vs 73 years [IQR, 69-78.5 years]; P < .001), more frequently male (86% vs 68%; P = .048), and had larger aneurysms (72.5 mm [IQR, 65.5-81 mm] vs 59 mm [IQR, 55-65 mm]; P < .001). Perioperative mortality was 1.8% for primary FEVAR and 2.7% for secondary FEVAR (P = .75). At 3 years, overall survival was 84% for primary FEVAR and 71% for secondary FEVAR (P = .086). Freedom-from reintervention was significantly higher for primary FEVAR than secondary FEVAR, specifically 82% vs 38% at 3 years (P < .001). Primary FEVAR also had more desirable sac dynamics relative to secondary FEVAR at 3 years (primary: 54% stable, 46% regressed, 0% expanded vs secondary: 33% stable, 28% regressed, and 39% expanded; P = .038).

CONCLUSIONS

FEVAR for primary aortic repair and FEVAR for rescue of prior EVAR with loss of proximal seal are two distinct entities. Following primary FEVAR, less than a quarter of patients have undergone reintervention at 3 years, and sac expansion was not seen in our cohort. Comparatively, 3 years after secondary FEVAR, over one-half of patients have undergone reintervention and over one-third have had ongoing sac expansion. Vigilant surveillance and a low threshold for further interventions are crucial following secondary FEVAR.

Midterm Outcomes and Aneurysm Sac Dynamics Following Fenestrated Endovascular Aneurysm Repair after Previous Endovascular Aneurysm Repair

OBJECTIVE

Fenestrated endovascular aneurysm repair (FEVAR) is a feasible option for aortic repair after endovascular aneurysm repair (EVAR), due to improved peri-operative outcomes compared with open conversion. However, little is known regarding the durability of FEVAR as a treatment for failed EVAR. Since aneurysm sac evolution is an important marker for success after aneurysm repair, the aim of the study was to examine midterm outcomes and aneurysm sac dynamics of FEVAR after prior EVAR.

METHODS

Patients undergoing FEVAR for complex abdominal aortic aneurysms from 2008 to 2021 at two hospitals in The Netherlands were included. Patients were categorised into primary FEVAR and FEVAR after EVAR. Outcomes included five year mortality rate, one year aneurysm sac dynamics (regression, stable, expansion), sac dynamics over time, and five year aortic related procedures. Analyses were done using Kaplan-Meier methods, multivariable Cox regression analysis, chi square tests, and linear mixed effect models.

RESULTS

One hundred and ninety-six patients with FEVAR were identified, of whom 27% (n = 53) had had a prior EVAR. Patients with prior EVAR were significantly older (78 ± 6.7 years vs. 73 ± 5.9 years, p < .001). There were no significant differences in mortality rate. FEVAR after EVAR was associated with a higher risk of aortic related procedures within five years (hazard ratio [HR] 2.6; 95% confidence interval [CI] 1.1 - 6.5, p = .037). Sac dynamics were assessed in 154 patients with available imaging. Patients with a prior EVAR showed lower rates of sac regression and higher rates of sac expansion at one year compared with primary FEVAR (sac expansion 48%, n = 21/44, vs. 8%, n = 9/110, p < .001). Sac dynamics over time showed similar results, sac growth for FEVAR after EVAR, and sac shrinkage for primary FEVAR (p < .001).

CONCLUSION

There were high rates of sac expansion and a need for more secondary procedures in FEVAR after EVAR than primary FEVAR patients, although this did not affect midterm survival. Future studies will have to assess whether FEVAR after EVAR is a valid intervention, and the underlying process that drives aneurysm sac growth following successful FEVAR after EVAR.

Comparative outcomes of physician-modified fenestrated/branched endovascular aortic aneurysm repair in the setting of prior failed endovascular aneurysm repair

OBJECTIVE

Endovascular treatment of aortic aneurysms involving renal-mesenteric arteries, especially in the setting of prior failed endovascular aneurysm repair (EVAR) typically requires fenestrated/branched endovascular aneurysm repair (F/BEVAR) with a custom-made device (CMD). CMDs are limited to select centers, and physician-modified endografts are an alternative treatment platform. Currently, there is no data on the outcomes of physician-modified F/BEVAR (PM-F/BEVAR) in the setting of failed prior EVAR. The purpose of this study was to evaluate the use of PM-F/BEVAR in patients with prior failed EVAR.

METHODS

A prospective database of consecutive patients treated at a single center with PM-F/BEVAR between March 2021 and November 2022 was retrospectively reviewed. The cohort was stratified by presence of a failed EVAR (type Ia endoleak or aneurysm development proximal to a prior EVAR) prior to PM-F/BEVAR. Demographics, operative details, and postoperative complications were compared between the groups using univariate analysis. One-year survival and freedom from reintervention were compared using the Kaplan-Meier method.

RESULTS

A total of 103 patients underwent PM-F/BEVAR during the study period; 27 (26%) were in the setting of prior EVAR. Patients with prior failed EVAR had similar age (75.2 ± 7.7 vs 71.5 ± 8.8 years; P = .058), male gender (n = 24 ; 89% vs n = 57 ; 75%; P = .130), and comorbid conditions except higher incidence of moderate-to-severe chronic obstructive pulmonary disease (n = 7 ; 26% vs n = 7 ; 9%; P = .047). Overall, aneurysm diameter was 65.5 ± 13.9 mm with aneurysms categorized as juxta-/pararenal in 43% and thoracoabdominal in 57%, with no differences between the groups. Twelve patients (14%) presented with symptomatic/ruptured aneurysms. The average number of target arteries incorporated per patient was 3.8. Four different aortic devices were modified with a greater proportion of Terumo TREO devices used in the failed EVAR group (P = .03). There was no difference in procedure time, radiation dose, or iodinated contrast use between groups. Overall technical success was 99%. Rates of 30-day mortality (n = 0 ; 0% vs n = 3 ; 4%; P = .565) and major adverse events (n = 6 ; 22% vs n = 16 ; 21%; P = 1.0) were similar between groups. For the overall cohort, rates of type 1 or 3 endoleak, branch vessel stenosis/occlusion, and reintervention were 2%, 1%, and 8%, respectively, with no difference between groups. One-year survival (failed EVAR 94% vs no EVAR 82%; P = .756) was similar between groups.

CONCLUSIONS

PM-F/BEVAR is a safe and effective treatment for patients with aneurysms involving the renal-mesenteric arteries in the setting of prior failed EVAR where additional technical challenges may be present. Additional follow-up is warranted to demonstrate long-term efficacy, but early results are encouraging and similar to those using CMDs.

Impact of stent-graft complexity on mid-term results in fenestrated endovascular aortic repair of juxtarenal and suprarenal abdominal aortic aneurysms

BACKGROUND

The impact of stent-graft complexity on clinical outcome after fenestrated endovascular aortic aneurysm repair (FEVAR) has been conflicting in the literature. The objective of this study was to compare mid-term results of stent-grafts with renal fenestrations alone with more complex stent-grafts including mesenteric fenestrations.

METHODS

A single center retrospective study was conducted on 154 patients, who underwent FEVAR from 2006 to 2020 at our institution.

RESULTS

There were 54 (35.1%) patients in the renal FEVAR group and 100 (64.9%) patients in the complex FEVAR group. Median follow-up of the total group was 25 months (IQR 7-45). There were no significant differences in technical success and perioperative mortality. Intraoperative complications (4% vs. 18%, P=0.001), operative time (145 min vs. 191 min, P=0.001), radiation dose (119372 mGy*cm² vs. 159573 mGy*cm², P=0.004) and fluoroscopy time (39 min vs. 54 min, P=0.007) were significantly lower in the renal FEVAR group. During follow-up target vessel instability, endoleaks and reinterventions were not significantly different between the two groups.

CONCLUSIONS

In this single center retrospective study, renal FEVAR was a safe and effective treatment for patients with juxtarenal AAA demonstrating fewer intraoperative complications and similar mid-term outcomes as complex FEVAR. If the anatomy is compatible for renal FEVAR, it might be unnecessary to expose patients to potentially more complications by choosing a complex FEVAR strategy.

Fenestrated-Branch Endovascular Repair After Prior Abdominal Aortic Aneurysm Repair

OBJECTIVE

To report the outcome of fenestrated and branch endovascular aortic repair (FEVAR-BEVAR) for asymptomatic and acute symptomatic proximal aortic pathology in patients with prior open (OSR) or endovascular (EVAR) abdominal aortic aneurysm (AAA) repair.

METHODS

This was a single centre retrospective study of consecutive patients with non-ruptured (asymptomatic and acute symptomatic) proximal aortic pathology after prior OSR or EVAR treated between December 2007 and February 2020. The primary endpoint was 30 day/in hospital mortality. Secondary endpoints were technical success, primary clinical success, and Kaplan-Meier estimates of medium term survival and freedom from re-intervention. Data are presented as median (interquartile range [IQR]). The effect of covariates on medium term survival was estimated using multivariable (Cox proportional hazards model) analysis. A p value < .05 was considered to be statistically significant.

RESULTS

Ninety-two patients (83 men; median age 75 years [IQR 71 - 80 years]; median diameter 73 mm [IQR 64 - 89 mm]; 82 elective, 10 acute) underwent FEVAR-BEVAR after prior OSR (n = 47) or EVAR (n = 45). Indications for intervention were aneurysmal degeneration with or without type 1a endoleak (n = 57; four juxtarenal [JR] AAA, 21 extent II/III, 32 extent IV thoraco-abdominal aortic aneurysms); type 1a endoleak alone (n = 27) and to create a more durable repair after acute infrarenal EVAR (n = 8; JRAAA). In total, 348 renovisceral vessels were targeted for preservation and 324 were stent grafted. Twenty-four unstented vessels comprised one bypass, 11 scallops and six fenestrations intentionally not stent grafted, two vessels occluded before graft implantation, and four vessels occluded intra-operatively. Primary technical success was 95.6%. The thirty day mortality rate was 1.1% and one patient each (1.1%) required permanent dialysis or developed temporary spinal cord ischaemia. Early primary clinical success was 94.6%. Median follow up was 36 months (IQR 23 - 64 months). Estimated overall survival (± standard error) at one, two, and three years was 86% ± 4%, 85% ± 4%, and 70% ± 5%, respectively. Multivariable analysis did not demonstrate any independent predictors of survival. Four target vessels occluded during follow up. Nineteen patients underwent 28 late re-interventions, with almost half performed for issues arising distal to the FEVAR-BEVAR. Patients treated with a cuff were statistically significantly more likely to require distal re-intervention compared with those treated by relining (9/49 vs. 1/43, p = .018 [odds ratio 9.3, 95% confidence interval 1.2 - 423]). In patients with prior EVAR alone, this did not reach statistical significance (cuff 7/25 vs. relining 1/20, p = .059 [odds ratio 7.1, 95% confidence interval 0.8 - 350]). Estimated freedom from re-intervention at one, two, and three years was 88% ± 3%, 81% ± 4%, and 81% ± 4%, respectively.

CONCLUSION

FEVAR-BEVAR after prior OSR or EVAR is associated with low peri-operative morbidity and mortality, and acceptable medium term survival and freedom from re-intervention. Treatment with a FEVAR-BEVAR cuff is associated with a higher requirement for distal re-intervention than relining of the original repair.

Rescue of proximal failure of endovascular abdominal aortic aneurysm repair with standard and fenestrated grafts

BACKGROUND

This study aimed to assess the outcomes of standard and fenestrated grafts to treat proximal failure of previous endovascular aneurysm repair (EVAR) in a tertiary referral center.

METHODS

All patients undergoing elective implantation of a standard or fenestrated graft after proximal failure of a previous EVAR between April 2010-November 2018 were included. Data were collected prospectively.

RESULTS

Fifty procedures were performed in 49 patients (45 male; mean age 74.6±7 years). A fenestrated proximal cuff was used in 24 (48%) cases, a composite bifurcated configuration in 21 (42%) cases, and EVAR in 5 (10%) cases. Technical success was achieved in all 5 EVAR cases and 41 of 45 FEVAR cases (91.1%). Iliac artery access problems due to the presence of the previous graft were encountered in eight (16%) procedures and renal artery catheterization difficulties in grafts with suprarenal fixation in seven (15.6%) procedures. There was one (2%) early death due to retroperitoneal bleeding. Early major complications occurred in three (6%) patients. Median follow-up was 26 months (range 1-77). Late occlusion occurred in two (1.3%) of the 151 targeted vessels. One patient needed permanent dialysis. Nine patients died during follow-up, one (2%) of them aneurysm-related. Ten (20.4%) patients presented with major complications during follow-up of which nine (18.4%) needed reintervention. Estimated freedom from reintervention at 1 and 3 years was 89.3±5.1% and 78.8±7.3%, respectively.

CONCLUSIONS

Repair with fenestrated grafts represents a safe and effective treatment option. Increased technical challenges are to be expected due to the previous graft.

Outcomes of endovascular treatment of endoleak type Ia after EVAR: a systematic review of the literature

INTRODUCTION

Endovascular repair of infra-renal aortic aneurysm (EVAR) has become treatment of choice. However, individuals undergoing EVAR have a high re-intervention rate. The aim of this study is to evaluate the current endovascular treatment modalities of endoleak type Ia (ET Ia) treatment after EVAR and their outcome.

EVIDENCE ACQUISITION

A systematic review and meta-analysis was performed. MEDLINE, EMBASE and Cochrane databases were searched with PRISMA methodology for studies reporting on endovascular treatment of ET Ia after EVAR. Studies presenting treatment of intra-operative ET Ia were excluded.

EVIDENCE SYNTHESIS

Two international registries, fourteen non-randomized retrospective and twelve case-report studies were included reporting on 356 patients. Reported endovascular techniques included fenestrated-, branched-, chimney EVAR, endovascular sealing (EVAS), endoanchors, embolization techniques, cuff and/or "giant" Palmaz stents. Technical success rate ranged from 90% to 100%, with intra-operative mortality rate of 0%. During early period, persistence of ET Ia was 3.4% (9/262) and the re-intervention rate was 3.5% (8/227). The 30-day mortality rate was 2% (7/356). Mean follow-up was 22.4 months±18. Presence of ET Ia was 5.9% (21/356), and the reintervention rate was 5.1% (18/349). The mortality rate was 13% (26/203), while the primary patency rate of TVs ranged from 94.3% to 100%.

CONCLUSIONS

A multitude of techniques for endovascular repair for ET Ia exists. No strong evidence supports one specific technique. The early and mid-term outcomes are encouraging in terms of ET Ia resolution, mortality and morbidity rates.

Abdominal aortic aneurysms

An abdominal aortic aneurysm (AAA) is a localized dilatation of the infrarenal aorta. AAA is a multifactorial disease, and genetic and environmental factors play a part; smoking, male sex and a positive family history are the most important risk factors, and AAA is most common in men >65 years of age. AAA results from changes in the aortic wall structure, including thinning of the media and adventitia due to the loss of vascular smooth muscle cells and degradation of the extracellular matrix. If the mechanical stress of the blood pressure acting on the wall exceeds the wall strength, the AAA ruptures, causing life-threatening intra-abdominal haemorrhage - the mortality for patients with ruptured AAA is 65-85%. Although AAAs of any size can rupture, the risk of rupture increases with diameter. Intact AAAs are typically asymptomatic, and in settings where screening programmes with ultrasonography are not implemented, most cases are diagnosed incidentally. Modern functional imaging techniques (PET, CT and MRI) may help to assess rupture risk. Elective repair of AAA with open surgery or endovascular aortic repair (EVAR) should be considered to prevent AAA rupture, although the morbidity and mortality associated with both techniques remain non-negligible.

Fenestrated and Branched Stent Grafting in Complex Aneurysmatic Aortic Disease: A Single-Center Early Experience

BACKGROUND

The aim of this study is to present our early experience and highlight the technical difficulties associated with the use of fenestrated and branched stent grafts to treat patients with juxtarenal abdominal aortic aneurysm (AAA), pararenal AAA, and thoracoabdominal aortic aneurysms (TAAAs).

METHODS

A prospectively held database maintained at our department was queried for patients who have undergone branched and fenestrated stent grafting for AAA or TAAA treatment. Indication for repair, comorbidity precluding open repair, technical challenges associated with the repair, as well as operative mortality, morbidity, and reintervention rate were evaluated.

RESULTS

A total of 8 patients underwent repair with a fenestrated or branched stent graft. All patients had aneurysmal degeneration of the juxtarenal aorta, pararenal aorta, and thoracoabdominal aorta not suitable to standard endovascular techniques. Two patients had a prior aortic repair, a failed migrated stent graft, and an old surgical tube graft after an open repair. One patient had a type III TAAA and 1 patient had a postdissection TAAA type I. For all patients, target vessel success rate was 96.4% (27/28) and mean hospital stay was 6.0 days (range 3-21). Thirty-day and 1-year mortality were 0%. Mean follow-up was 23 months (range 7-45). Two endoleaks occurred, 1 type III and 1 type II, which were treated endovascularly. No death or major complication occurred during follow-up.

CONCLUSIONS

Fenestrated and branched endovascular stent grafts can be used to repair juxtarenal AAA, pararenal AAA, and TAAA in patients with significant comorbidities. However, several technical challenges have to be overcome due to the unique complex aortic pathology of each patient.

An Uncommon Case of Type III Endoleak Treated with a Custom-made Thoracic Stent Graft

Endovascular aortic repair (EVAR) has been shown to be a valid and minimally invasive alternative to open abdominal aortic aneurysm repair. A major shortcoming for EVAR is the need to submit patients to regular follow-up to detect potential complications such as endoleak, limb occlusion, aneurysm expansion, aneurysm rupture, infection, structural failure, and migration. In this case report, we describe an uncommon case of late type III endoleak due to complete detachment of the stent-graft main body segment from its suprarenal uncovered fixation stent. It was treated with a custom-made Relay(®) NBS Plus (Bolton Medical, Barcelona, Spain) thoracic stent graft which also provided extra suprarenal fixation of the thoracic stent graft in the proximal neck. The postoperative period was uneventful and a computed tomography scan 1 year later revealed proper positioning of the stent graft and no signs of endoleak. The successful strategy chosen to correct this complication was at the same time original and infrequent, and also avoided potential complications related to open surgical repair and general anesthesia.

Anchoring barbs and balloon expandable stents: what is the risk of perforation and failed stent deployment?

PURPOSE

Balloon expandable stents may on occasion be deployed in close proximity to the anchoring barbs of endovascular grafts. The aim of this study was to determine the risk and effect of balloon perforation by anchoring barbs and to assess whether these risks are different if the balloon is protected by a covered stent mounted upon it.

METHODS

A bench-top model was developed to mimic the penetration of anchoring barbs into the lumen of medium sized blood vessels. The model allowed variation of angle and depth of vessel penetration. Both bare balloons and those with covered stents mounted upon them were tested in the model to determine whether there was a risk of perforation and which factors increased or decreased this risk.

RESULTS

All combinations of barb angle and depth caused balloon perforation but this was most marked when the barb was placed perpendicular to the long axis of the balloon. When the deployment of covered stents was attempted balloon perforation occurred in some cases but full stent deployment was achieved in all cases where the perforation was in the portion of the balloon covered by the stent. The only situation in which stent deployment failed was where the barb was intentionally placed in the uncovered portion of the balloon. This resulted in only partial deployment of the stent.

CONCLUSIONS

Balloon rupture is a distinct possibility when deploying balloon-expandable stents in close proximity to anchoring barbs. Care should be taken in this circumstance to ensure that the barb is well away from the uncovered portion of the balloon.

Fenestrated aortic stent grafts

Fenestrated stent grafts have been developed to offer an endovascular treatment option to those patients with abdominal aortic aneurysms whose infrarenal necks are anatomically unsuitable for endovascular repair with standard infrarenal devices. The ability to have customized fenestrations that will preserve flow to essential visceral arteries allows proximal seal and fixation to be achieved at and above the renal level. This article discusses patient selection, stent-graft design, and the importance of accurate planning. Deployment techniques along with complications and their avoidance are considered. The published midterm results are reviewed and appear to justify the continued use and evaluation of this technique as an alternative to open surgical repair in high-risk patients with infrarenal necks unsuitable for standard endovascular repair.

Ethylene vinyl alcohol copolymer (Onyx) to seal type 1 endoleak. A new technique

The aim of this study was to investigate whether the liquid embolic agent Onyx, an ethylene vinyl alcohol copolymer, can be used to seal type 1 endoleaks during endovascular aortic repair (EVAR). Six patients with large aortic aneurysms and remaining type 1 endoleaks during or after EVAR were treated with Onyx embolization through a microcatheter placed in the proximal neck in five cases and in the distal neck in one case. Four of the patients were treated using the chimney technique. The type 1 endoleak was primarily sealed by Onyx in all six patients. There was no distal embolization. Two patients had complications during follow-up. One patient had occlusions of chimney grafts to the renal arteries and to one leg extension. These occlusions were not anatomically related to Onyx embolization. One patient had late stentgraft migration of the Onyx-treated distal neck with aneurysm rupture 18 months after treatment. Early experience of Onyx embolization as a bailout solution of type 1 endoleaks after complicated EVAR is promising. However, effective seal with Onyx does not prevent late stentgraft migration. More reported patients and longer follow-up are necessary to evaluate this new technique.

Three-year follow-up of fenestrated thoracoabdominal stent graft bridging an endovascular thoracic stent graft and a surgical abdominal aortic graft

This case report describes repair of a type I endoleak at the distal landing zone of a thoracic aortic stent graft by endovascular placement of a thoracoabdominal fenestrated stent graft (Cook, Brisbane, Australia). The fenestrated stent graft was interposed between a previous abdominal aortic aneurysm (AAA) Gelsoft tube graft (Sulzer Vascutek Ltd, Inchinnan, United Kingdom) and two overlapping Zenith thoracic endografts (Cook Inc, Bloomington, Indiana). Placement was made more complex because the distal thoracic endograft had rotated into a horizontal position. At 3-year clinical and computed tomography (CT) follow-up, continued clinical and radiologic success was shown with no further intervention required.