Fenestrated endovascular aortic aneurysm repair using physician-modified endovascular grafts versus company-manufactured devices

Cause of death among patients following repair of juxtarenal aneurysm with physician-modified endografts

OBJECTIVE

The use of physician-modified endografts (PMEGs) to treat juxtarenal aortic aneurysms has increased significantly over the past 10 years. However, there exists a paucity of data beyond 5 years. This study compares long-term outcomes and cause of death between patients who did and did not survive beyond 5 years after PMEG for juxtarenal aneurysm.

METHODS

All patients with >5 years of follow-up data enrolled in a prospective, physician-sponsored investigational device exemption clinical trial treated with PMEG for juxtarenal aneurysm were included. Univariate analysis was used to compare demographics, anatomical and operative characteristics, late outcomes, and cause of death between patients who survived beyond 5 years and those who did not. Death on hospice, clinical follow-up status, and whether patients declined a secondary intervention were also evaluated. Survival was assessed with Kaplan-Meier analysis. Predictors of overall mortality and mortality before 5 years were determined using Cox regression analysis.

RESULTS

We included 98 patients with juxtarenal aneurysm wgo underwent PMEG from 2011 to 2018; 64 (65.3%) survived beyond 5 years and 34 (34.7%) did not. Patients who survived beyond 5 years were younger (73 years vs 78 years; P = .04) with a greater prevalence of preoperative antiplatelet use (81.3% vs 61.8%; P = .047). There were no differences in comorbidities, symptomatic presentation, or anatomical or operative characteristics. Patients who survived beyond 5 years were less likely to experience a perioperative adverse event (10.9% vs 38.2%; P < .01) and pulmonary complication (1.6% vs 17.7%; P = .01). There were no differences in late outcomes, including reintervention, aortic sac behavior, endoleak, or visceral patency. Patients who survived beyond 5 years more frequently died on hospice (58.6% vs 17.6%; P < .01), were lost to aortic-specific clinical follow-up (48.4% vs 5.9%; P < .01), and declined a secondary intervention (9.4% vs 2.9%; P = .04). For the entire study cohort, aortic-related mortality was 9.5%. Survival was 87% at 1 year, 65% at 5 years, and 10% at 10 years. Cardiac comorbidities (15.9%), systemic decline (15.9%), stroke (14.2%), and cancer (12.9%) accounted for the leading causes of death, with no differences between the two cohorts. On adjusted analysis, sac regression was associated with reduced mortality for the entire patient cohort (hazard ratio [HR], 0.37; 95% confidence interval [CI], 0.18-0.76) and those who died before 5 years (HR, 0.37; 95% CI, 0.16-0.92). Meanwhile, congestive heart failure (HR, 6.02; 95% CI, 1.60-22.65) was associated with increased mortality for patients who did not survive beyond 5 years.

CONCLUSIONS

Patients who undergo PMEG for juxtarenal aneurysm are more likely to die from underlying medical comorbidities; aortic-related mortality accounts for <10% of total deaths. Patients who do not survive beyond 5 years are older and experience more perioperative complications, whereas patients who survive beyond 5 years are more likely to die on hospice, be lost to clinical follow-up, and decline a secondary intervention. These findings reflect the high degree of chronic disease burden for this patient population, even after successful treatment of their aortic pathology.

Development of a method to achieve antegrade in situ fenestration of endovascular stent grafts in abdominal aortic aneurysms

Abdominal aortic aneurysm (AAA) is the focal dilation of the terminal aorta, which can lead to rupture if left untreated. Traditional endovascular aneurysm repair techniques are minimally invasive and pose low mortality rates compared with open surgical repair; however, endovascular aneurysm repair procedures face challenges in accommodating variations in the patient's anatomy. Complex aneurysms are defined when the sac extends past the renal arteries or has an insufficient neck landing zone to deploy a traditional endograft. Fenestrated endografts were introduced to enable the repair of complex aneurysms by the creation of fenestrations to enable blood flow into the visceral arteries. This study investigates proof of concept for creating antegrade in situ fenestrations of off-the-shelf endografts using a novel endovascular orifice detection device. Our technique enables the precise location of the visceral artery orifices using fiber optic cables and an infrared light source. The endovascular orifice detection device was tested rigorously in precisely locating an artery opening in blood and a custom AAA phantom model. The study also explored the safest means of creating a fenestration using mechanical puncture and a laser. This innovative approach offers a viable alternative for patients with complex AAAs.

Fenestrated Endovascular Aortic Repair After Failed Endovascular Aortic Repair

PURPOSE

Fenestrated endovascular aortic repair (FEVAR) is technically more challenging when performed after a failing EVAR procedure (FEVAR after EVAR). This study aims to assess the technical outcome of FEVAR after EVAR and to identify factors that may influence complication rates.

METHODS

A retrospective observational study was conducted at a single department of vascular and endovascular surgery. The rate of FEVAR after EVAR compared to primary FEVAR is reported. Complication and primary unconnected fenestration (PUF) rates as well as survival were assessed for the FEVAR after EVAR cohort. PUF rates and operating time were also compared to all primary FEVAR patients. Patient characteristics and technical factors such as number of fenestrations or use of a steerable sheath were assessed as possible influencers on technical success when performing FEVAR after EVAR.

RESULTS

Two hundred and nine fenestrated devices were implanted during the study period (2013 to April 2020). Thirty-five patients (16.7% of all FEVAR patients) had undergone FEVAR after EVAR and were included in the study. Overall survival at last follow-up (20.2±19.1 months) was 82.9% in FEVAR after EVAR patients. Rates of technical failure dropped significantly after 14 procedures (42.9% vs. 9.5%; p=0.03). Primary unconnected fenestrations were seen in 3 cases of FEVAR after EVAR (8.6%) and 14 of 174 primary FEVAR cases (8.0%; p>0.99). Operating time for FEVAR after EVAR was significantly higher than for primary FEVAR (301.1±110.5 minutes vs. 253.9±103.4 minutes; p=0.02). The availability of a steerable sheath was a significant predictor of reduced risk of PUFs, whereas age and gender, number of fenestrations or suprarenal fixation of the failed EVAR did not significantly influence PUF rates.

CONCLUSION

Fewer technical complications were seen over the study period in FEVAR after EVAR patients. While rates of PUFs were not different from primary FEVAR, operating time was significantly longer in patients undergoing FEVAR for failed EVAR. Fenestrated EVAR can be a valuable and safe tool to treat patients with progression of aortic disease or type Ia endoleak after EVAR but may be more complex to achieve than primary FEVAR.

CLINICAL IMPACT

This retrospective study assesses the technical outcome of fenestrated endovascular aortic repair (fenestrated EVAR; FEVAR) after prior EVAR. While rates of primary unconnected fenestrations were not different from primary FEVAR, operating time was significantly longer in patients undergoing FEVAR for failed EVAR. Fenestrated EVAR after prior EVAR may be technically more challenging than primary FEVAR procedures, but could be performed with equally good results in this patient cohort. FEVAR offers a feasible treatment option for patients with progression of aortic disease or type Ia endoleak after EVAR.

Ten years of physician-modified endografts

OBJECTIVES

Physician-modified endografts (PMEGs) have expanded the scope of endovascular abdominal aortic repair beyond the infrarenal aorta. Patients with prohibitively high surgical risk and visceral segment disease are often candidates for this intervention, which mitigates much of the morbidity and mortality associated with conventional open repair. Here we present the institutional PMEG experience of a high-volume aortic center.

METHODS

We studied all PMEGs performed at our institution from 2012 to 2023. We included cases that were submitted to the US Food sand Drug Administration in support of an investigational device exemption (IDE) trial, as well as those in the subsequently approved IDE trial. Over this 11-year period, we assessed the changes in operative characteristics and perioperative outcomes over time. Additionally, we compared the outcomes from PMEG cases to those of Zenith fenestrated (ZFEN) grafts (done by the surgeon with the PMEG IDE), an alternative device used for aneurysms involving the lower visceral segment. Here we assessed operative characteristics, perioperative outcomes, and 5-year survival and reintervention rates.

RESULTS

When assessing the change over time for PMEG operative characteristics, we found a trend toward decreased fluoroscopy time and decreased proportions of completion type I and type III endoleaks (all P < .05). Perioperative outcomes have remained stable over this period, with an overall perioperative mortality rate of 4.9% (noting that this registry also includes cases that were urgent and emergent). Despite the increased complexity of PMEGs relative to ZFENs, we found comparable perioperative outcomes with regard to mortality (4.9% vs 4.3%; P = .86), permanent spinal cord ischemia (1.1% vs 0%; P = .38), postoperative myocardial infarction (4.3% vs 2.9%; P = .60), postoperative respiratory failure (7.1% vs 4.3%; P = .43), and new dialysis use (2.2% vs 4.3%; P = .35). Additionally, 5-year survival (PMEG 54% vs ZFEN 65%; P = .15) and freedom from reintervention (63% vs 74%; P = .07) were similar between these cohorts.

CONCLUSIONS

Throughout our >10-year experience with PMEGs, we have noted improvements in operative outcomes, which can likely be attributed to technological advances and increased physician experience. Additionally, we have found that PMEGs perform well when compared with ZFENs, despite being a more complicated repair that is able to treat a larger segment of the aorta. PMEGs are crucial for the comprehensive care of vascular patients with complex aortic disease. As further operative advancements are made, we only expect the use of this intervention to increase.

Early experience with patient-specific unibody bifurcated fenestrated-branched devices for complex endovascular aortic aneurysm repair

OBJECTIVE

Short distances between the lowest visceral/renal artery and the aortic bifurcation are technically challenging during complex endovascular aortic aneurysm repair (EVAR), particularly after previous infrarenal repair. Traditionally, inverted limb bifurcated devices have been used in addition to fenestrated-branched (FB) endografts, but short overlap, difficult cannulation, and potential crushing of bridging stents are limitations for their use. This study reviews the early experience of patient-specific company manufactured devices (PS-CMDs) with a unibody bifurcated FB design for complex EVAR.

METHODS

Consecutive complex EVAR procedures over a 34-month period with unibody bifurcated FB-devices as part of physician-sponsored investigational device exemption studies at two institutions were reviewed. Unibody bifurcated FB designs included FB bifurcated or fenestrated inverted limb devices. End points included technical success, survival, frequency of type I or III endoleaks, limb occlusion, and secondary interventions.

RESULTS

Among 168 patients undergoing complex EVAR, 33 patients (19.6%; 78.7% male; mean age, 77 years) received unibody bifurcated FB PS-CMDs. FB bifurcated and fenestrated inverted limb devices were used in 31 (93.9%) and 2 (6.06%) patients, respectively. The median maximum aneurysm diameter was 61 mm (interquartile range [IQR], 55-69 mm). Prior EVAR was reported by 29 patients (87.9%), of whom 2 (6.06%) had suprarenal stents. A short distance between the lowest renal artery and aortic bifurcation was demonstrated in 30 patients (90.9%), with median distance of 47 mm (IQR, 38-54 mm). Preloaded devices were used in 23 patients (69.7%). A total of 128 fenestrations were planned; 22 (17.2%) were preloaded with guidewires and 5 (3.9%) with catheters. The median operative time was 238 minutes (226-300 minutes), with a median fluoroscopy time of 65.5 minutes (IQR, 56.0-77.7 minutes) and a median dose area product of 147 mGy∗cm2 (IQR, 105-194 mGy∗cm2). Exclusive femoral access was used in 14 procedures (42.4%). Technical success was 100%. Target vessel primary patency was 100% at a median follow-up time of 11.7 months (IQR, 3.5-18.6 months). Two patients (6.06%) required reintervention for iliac occlusion; one patient required stenting and the other a femoral-femoral bypass. No aortic-related deaths occurred after the procedure. During follow-up, 11 type II endoleaks (33.3%) and 1 type Ib endoleak (3.03%) were detected; the latter was treated with leg extension. No type Ia or III endoleaks occurred.

CONCLUSIONS

Complex EVAR using unibody bifurcated FB-PS-CMDs is a simple, safe, and cost-effective alternative for the treatment of patients with short distances between the renal arteries and the aortic bifurcation. Further studies are required to assess benefits and durability of unibody bifurcated FB devices.

Monocentric Evaluation of Physician-Modified Fenestrations or Parallel Endografts for Complex Aortic Diseases

PURPOSE

This study aimed to investigate the demographic and anatomic characteristics, as well as perioperative and follow-up results of fenestration and parallel techniques for the endovascular repair of complex aortic diseases.

MATERIALS AND METHODS

A retrospective study was conducted on 67 consecutive patients underwent endovascular treatment for complex aortic diseases including abdominal aortic aneurysm (AAA), thoracoabdominal aneurysm (TAAA), aortic dissection, or prior endovascular repair with either fenestrated and parallel endovascular aortic repair (f-EVAR or ch-EVAR) at a single institute from 2013 to 2021. Choices of intervention were made by the disease' emergency, patients' general condition, the anatomic characteristics, as well as following the recommendation from the devices' guidelines. Patients' clinical demographics, aortic disease characteristics, perioperative details, and disease courses were discussed. Short- and mid-term follow-up results were obtained and analyzed. Endpoints were aneurysm-related and unrelated mortality, branch instability, and renal function deterioration.

RESULTS

Totally, 34 and 27 patients received f-EVAR and ch-EVAR, while 6 patients received a combination of both. Fenestrated endovascular aortic repair was conducted mainly in AAA affecting visceral branches and TAAA, whereas ch-EVAR was normally utilized for infrarenal AAA. Regarding the average number of reconstructed arteries per patient, there was a significant difference among f-EVAR, ch-EVAR, and the combination group (mean = 2.3 ± 0.9, 1.4 ± 0.6, 3.5 ± 0.5, p<0.001). Primary technical success was achieved in 28 (82.4%), 22 (81.5%), and 3 (50.0%) patients for each group. Besides operational time (5.77 ± 2.58, 4.47 ± 1.44, p=0.033), no significant difference was observed for blood transfusion, intensive care unit (ICU) or hospital stay, blood creatinine level, 30-day complications, or follow-up complications between patients undergoing f-EVAR or ch-EVAR. Patients receiving combination of both techniques had a higher rate of blood transfusion (p=0.044), longer operational time (p=0.008) or hospital stay (p=0.017), as well as more stent occlusion (p=0.001), endoleak (p=0.004) at short-term and a higher rate of endoleak (p=0.023) at mid-term follow-up.

CONCLUSION

In conclusion, this study demonstrated that f-EVAR and ch-EVAR techniques had acceptable perioperative and follow-up results and should be considered viable alternatives when encountering complex aortic diseases.

CLINICAL IMPACT

This study sought to investigate the baseline and pathological characteristics, as well as perioperative and follow-up results of f-EVAR and ch-EVAR at a single Chinese institution. F-EVAR (mostly physician-modified f-EVAR) was applied in patients with a wide range of etiologies and disease types, while ch-EVAR was preferred for AAA in older patients with an average higher ASA grade. Our experience suggested acceptable safety and efficacy both for techniques, and no significant difference was observed between the two groups regarding any short or mid-term adverse events.

Enlarging Paravisceral Aortic Aneurysm Treated With In Situ Laser Fenestration of Physician-Modified Stent Graft for Preservation of Accessory Renal Arteries

PURPOSE

In situ laser fenestration (LISF) was performed as a bailout procedure to ensure renal perfusion during complex aortic aneurysm repair.

CASE REPORT

A 69 year-old male patient with previous repair of abdominal aortic aneurysm who presented with increasing lower back pain and an enlarging, 6-cm, perivisceral aortic aneurysm that required urgent repair. Given potential complications and risks of redo open repair, we performed endovascular repair via deployment of a 5-vessel fenestrated physician modified stent graft (PMEG) with stent placement to the celiac, superior mesenteric, right renal, and 2 of the larger 3 left renal arteries. The renal artery planned for sacrifice was found intraoperatively to be perfusing a large portion of the kidney. Subsequently, LISF was used to cannulate and salvage perfusion to the third renal artery. Completion aortogram demonstrated patency of all renal visceral vessels with no vessel leak. Follow-up CT angiogram 1 year later demonstrated aortic graft with all visceral stents patent, no endoleak, and a reduction in residual aneurysm sac.

CONCLUSION

Even with careful planning and design of a physician modified stent graft, in situ laser fenestration provides an option to successfully create additional stents intraoperatively in order to preserve perfusion to critical visceral organs.

CLINICAL IMPACT

In situ laser fenestration will provide surgeons with a valuable intra-operative method to create additional stents when organ perfusion would otherwise be lost. As more surgeons develop this technical ability and more long-term outcomes are studied, this method has the possibility to not only be used for urgent and emergent cases but may one day be an acceptable variation to standard practice.

Long-Term Results of Physician-Modified Endografts for the Treatment of Elective, Symptomatic, and Ruptured Juxtarenal Abdominal Aortic Aneurysms

OBJECTIVE

The objective of this study was to report long-term results of an ongoing physician-sponsored, investigational device exemption (IDE) pivotal clinical trial using physician-modified endovascular grafts (PMEGs) for the treatment of patients with juxtarenal aortic aneurysms.

METHODS

Data from a nonrandomized, prospective, consecutively enrolling IDE clinical trial were used. Data collection began on April 1, 2011, and data lock occurred on January 2, 2024, with outcomes analysis through December 31, 2023. Primary safety and effectiveness end points were used to measure treatment success. The safety end point was defined as the proportion of subjects who experienced a major adverse event within 30 days of the procedure. The effectiveness end point was the proportion of subjects who achieved treatment success. Treatment success required the following at 12 months: technical success, defined as successful delivery and deployment of a PMEG with preservation of intended branch vessels; and freedom from: type I and III endoleak, stent graft migration >10 mm, aortic aneurysm sack enlargement >5 mm, and aortic aneurysm rupture or open conversion.

RESULTS

Over the 12-year study period, 228 patients were enrolled; 205 began the implant procedure, and 203 received PMEG. Thirteen patients withdrew prior to PMEG. Two withdrew (<1.0%) after failure to deploy due to tortuous iliac anatomy and are tracked as intent to treat, and a total of 24 withdrew after receiving the PMEG implant. Forty-four patients died during the study period. A total of 14 were deemed lost to follow-up. Fifty-nine completed the 5-year follow-up period, and 62 remain active in follow-up visits.Aneurysm anatomy, operative details, and lengths of stay were recorded and included: aneurysm diameter (mean, 67.5 mm; range, 49-124 mm), proximal seal zone length (mean, 41.6 mm; range, 18.9-92.9 mm), graft modification time (mean, 48.7 min), procedure time (mean, 137.7 min), fluoroscopy time (mean, 33.8 min), contrast material use (mean, 93.0 mL), estimated blood loss (mean, 118.8 mL), length of hospital stay (mean, 3.7 d), and intensive care unit length of stay (mean, 1.6 d).A total of 575 fenestrations were created for 387 renal arteries, 181 superior mesenteric arteries (SMAs), and 7 celiac arteries. Renal arteries were in 96% of patients and included 410 renal artery stents in 203 patients. The SMA was stented as needed and included one patient with an SMA stent placed before the procedure, 19 during the procedure, and 2 patients who underwent stent placement after the procedure. There were no open conversions or device migrations and 1 partial explant due to late distal graft occlusion. Three ruptures (1.4%) were recorded on days 830, 1346, and 1460. There was 1 presumed graft infection at 750 days (<0.5%) treated with? Thirty-day all-cause mortality was 2.9% (6/204). One type Ia, 1 type Ib, and 7 type III endoleaks were identified during follow-up and treated with successful reintervention at the 1-year period. The overall rate of major adverse events at 30 days was 15% (29/194). Technical success was 93.7%, and overall treatment success was 82.6%.

CONCLUSIONS

PMEG can be performed with low rates of long-term morbidity and mortality, confirming our early and midterm reports that endovascular repair with PMEG is safe, durable, and effective for managing patients with juxtarenal aortic aneurysms. While historically considered experimental, these results suggest that PMEG is a safe and durable option and should be considered for patients where off-the-shelf devices are not available.

Physician-Modified Endografts with the TREO Stent Graft System

PURPOSE

Description of physician-modified endograft technique and its advantages using the TREO stent graft system.

TECHNIQUE

After partial back-table deployment of the TREO endograft, fenestrations are created using a scalpel and reinforced with a double snare loop and running suture. The distance between the Z-shaped stents of the TREO main body of almost 20 mm allows for more flexible placement of multiple fenestrations and easier and faster re-sheathing. The technique is illustrated with physician modification of a TREO aortic cuff and bifurcated endograft in three patients with juxtarenal aortic aneurysms or type Ia endoleak after previous endovascular aortic aneurysm repair.

CONCLUSION

Physician modification of the TREO stent graft system can be safely performed, making it an excellent additional option to treat juxtarenal aneurysms.

CLINICAL IMPACT

The TREO stent graft system offers various sizing options including different main body lengths and diameters, thus increasing applicability. Larger distance between the main body's stents facilitates placement of multiple physician-modified fenestrations. Re-sheathing is easier and faster due to the low number of main body stents which have to be re-sheathed. Therefore, the TREO stent graft system is an excellent platform for the physician-modified technique.

One-hundred Consecutive Physician-Modified Fenestrated Endovascular Aneurysm Repair of Pararenal and Thoracoabdominal Aortic Aneurysms Using the Terumo TREO Stent Graft

BACKGROUND

Fenestrated endovascular aortic aneurysm repair (FEVAR) has been widely applied for the treatment of pararenal (PAA) and thoracoabdominal aortic aneurysms (TAAA). If custom-made devices or off-the-shelf devices are not available, physician-modified endografts (PMEGs) are an alternative device option. Several different endograft platforms have been used for PMEG; however, minimal data exists on utilizing the Terumo TREO abdominal stent graft system in this setting. The purpose of this study was to evaluate our single-center experience treating PAA and TAAA, with a physician-modified FEVAR, using the Terumo TREO platform.

METHODS

A prospective database of consecutive patients with PAA and TAAA treated at a single center, with a FEVAR, utilizing a PMEG device between March 2021 and September 2023 was queried for those having a Terumo TREO device implanted. The demographics, operative details, and postoperative complications were analyzed. The rates of technical success, type I or III endoleak, branch vessel status, reintervention, and 2-year survival were also assessed.

RESULTS

Of the 153 patients who underwent FEVAR with a PMEG device during the study period, 100 had repair using a Terumo TREO stent graft. The mean age of the cohort was 73.7 ± 7.0 years with the majority suffering from hypertension (n = 94, 94%), coronary artery disease (n = 51, 51%), and chronic obstructive pulmonary disease (n = 40, 40%). Thirty-four patients (34%) had a prior failed EVAR device in place. The mean aneurysm size was 66.0 ± 13.7 mm, with 58 (50%) patients classified as PAA and 30 (30%) patients as an extent IV TAAA. Six (6%) patients presented with symptomatic/ruptured aneurysms. The average number of target arteries incorporated per patient was 3.8 ± 0.6. The overall technical success was 99%, procedure time was 218 ± 116 min, contrast volume was 82 ± 21 mL, and cumulative air kerma was 3,054 ± 1,560 mGy. Postoperative complications were present in 20 patients (20%), and 2 patients (2%) died within 30 days. Rates of type I or III endoleak, branch vessel stenosis or occlusion, and reintervention were 2%, 1%, and 7%, respectively. The two-year overall survival was 87%.

CONCLUSIONS

Treatment of PAA and the extent IV TAAA using a physician-modified fenestrated Terumo TREO endograft is safe and effective. This large, early experience using the Terumo TREO platform supports preferential use of this device in this setting due to the device design and low likelihood of type I or III endoleak.

Early Financial Outcomes of Physician Modified Endograft Programs Are Dictated by Device Cost

INTRODUCTION

Physician-modified endografts (PMEGs) have been used for repair of thoracoabdominal aortic aneurysms (TAAAs) for 2 decades with good outcomes but limited financial data. This study compared the financial and clinical outcomes of PMEGs to the Cook Zenith-Fenestrated (ZFEN) graft and open surgical repair (OSR).

METHODS

A retrospective review of financial and clinical data was performed for all patients who underwent endovascular or OSR of juxtarenal aortic aneurysms and TAAAs from January 2018 to December 2022 at an academic medical center. Clinical presentation, demographics, operative details, and outcomes were reviewed. Financial data was obtained through the institution's finance department. The primary end point was contribution margin (CM).

RESULTS

Thirty patients met inclusion criteria, consisting of twelve PMEG, seven ZFEN, and eleven open repairs. PMEG repairs had a total CM of -$110,000 compared to $18,000 for ZFEN and $290,000 for OSR. Aortic and branch artery implants were major cost-drivers for endovascular procedures. Extent II TAAA repairs were the costliest PMEG procedure, with a total device cost of $59,000 per case. PMEG repairs had 30-d and 1-y mortality rates of 8.3% which was not significantly different from ZFEN (0.0%, P = 0.46; 0.0%, P = 0.46) or OSR (9.1%, P = 0.95; 18%, P = 0.51). Average intensive care unit and hospital stay after PMEG repairs were comparable to ZFEN and shorter than OSR.

CONCLUSIONS

Our study suggests that PMEG repairs yield a negative CM. To make these cases financially viable for hospital systems, device costs will need to be reduced or reimbursement rates increased by approximately $8800.

Comparison of the Snare Loop Technique and the Hungaroring Reinforcement for Physician-Modified Endograft Fenestrations-An In Vitro Study

BACKGROUND

We conducted an in vitro comparison of the snare loop reinforcement against a closed-loop reinforcement (Hungaroring) for physician-modified endograft (PMEG) fenestrations regarding preparation time and stability during flaring balloon dilatation.

MATERIALS AND METHODS

The time to complete a PMEG fenestration with reinforcement was measured and compared between the Hungaroring and snare loop groups. The number of stitches was counted. Each fenestration was dilated using a 10 mm high-pressure, non-compliant balloon up to 21 atm in pressure, and fluoroscopic images were taken. The presence of indentation on the oversized balloon at the level of the reinforcement was evaluated at each fenestration.

RESULTS

Five fenestrations were created in each group (n = 5) for a total of ten pieces. The completion time in the snare loop group was 1070 s (IQR:1010-1090) compared to 760 s (IQR:685-784) in the Hungaroring group (p = 0.008). Faster completion time was achieved by faster stitching (23.2 s/stitch (IQR 22.8-27.3) for the snare loop group and 17.3 s/stitch (IQR 17.3-20.1) for the Hungaroring group (p = 0.016). None of the fluoroscopic images of the snare loop reinforcement showed an indentation on the balloon during the overexpansion; on the contrary, the Hungaroring showed indentation in every case, even at 21 atm.

CONCLUSION

Fenestrations reinforced with Hungaroring can be completed significantly faster. Furthermore, the Hungaroring resists over-dilation even at high pressures, while snare loop reinforcements dilate at nominal pressure.

Midterm outcomes of physician-modified endovascular stent grafts for the treatment of complex abdominal aortic aneurysms in Korea: a retrospective study

Purpose

Physician-modified endovascular stent grafts (PMEG) are a good treatment option for complex abdominal aortic aneurysms (AAAs), especially in high-risk patients not amenable to open repair, and when commercial fenestrated devices are not available. We report our single-center experience with PMEG for the treatment of complex AAAs.

Methods

We retrospectively reviewed patients who underwent PMEG repair for AAA from November 2016 to September 2020 at our institution. Demographic data, anatomic characteristics, perioperative and postoperative outcomes, major adverse events, and 30-day mortality were analyzed.

Results

We identified 12 patients who underwent PMEG for complex AAA. The mean age was 74 years and the mean maximal AAA diameter was 58.1 mm. Indications for treatment included 4 impending or contained ruptures, 2 mycotic aneurysms, and 6 symptomatic cases. The technical success rate was 91.7%. Aneurysm sac regression was observed in 7 patients (58.3%), including 2 cases of complete regression. There was 1 aneurysm-related mortality at 3 months due to mycotic aneurysm. Also, there was 1 postoperative complication case of transient renal failure requiring temporary dialysis. At 1 year, there was 1 branch occlusion from the initial failed cannulation case and 2 type 1A endoleaks, and there was 1 case of open explantation.

Conclusion

PMEG showed a low technical failure rate and acceptable midterm stent durability and sac stability, comparable to conventional endovascular aneurysm repair. Despite the small number of cases, there was a tendency for a high sac regression rate, although longer follow-up is needed.

Outcomes of Elective and Non-elective Fenestrated-branched Endovascular Aortic Repair for Treatment of Thoracoabdominal Aortic Aneurysms

OBJECTIVE

To describe outcomes after elective and non-elective fenestrated-branched endovascular aortic repair (FB-EVAR) for thoracoabdominal aortic aneurysms (TAAAs).

BACKGROUND

FB-EVAR has been increasingly utilized to treat TAAAs; however, outcomes after non-elective versus elective repair are not well described.

METHODS

Clinical data of consecutive patients undergoing FB-EVAR for TAAAs at 24 centers (2006-2021) were reviewed. Endpoints including early mortality and major adverse events (MAEs), all-cause mortality, and aortic-related mortality (ARM), were analyzed and compared in patients who had non-elective versus elective repair.

RESULTS

A total of 2603 patients (69% males; mean age 72±10 year old) underwent FB-EVAR for TAAAs. Elective repair was performed in 2187 patients (84%) and non-elective repair in 416 patients [16%; 268 (64%) symptomatic, 148 (36%) ruptured]. Non-elective FB-EVAR was associated with higher early mortality (17% vs 5%, P <0.001) and rates of MAEs (34% vs 20%, P <0.001). Median follow-up was 15 months (interquartile range, 7-37 months). Survival and cumulative incidence of ARM at 3 years were both lower for non-elective versus elective patients (50±4% vs 70±1% and 21±3% vs 7±1%, P <0.001). On multivariable analysis, non-elective repair was associated with increased risk of all-cause mortality (hazard ratio, 1.92; 95% CI] 1.50-2.44; P <0.001) and ARM (hazard ratio, 2.43; 95% CI, 1.63-3.62; P <0.001).

CONCLUSIONS

Non-elective FB-EVAR of symptomatic or ruptured TAAAs is feasible, but carries higher incidence of early MAEs and increased all-cause mortality and ARM than elective repair. Long-term follow-up is warranted to justify the treatment.

Fenestrated Physician-Modified Endografts for Preservation of Main and Accessory Renal Arteries in Juxtarenal Aortic Aneurysms

BACKGROUND

There is a paucity of reporting outcomes of complex aortic aneurysm treatment such as juxtarenal abdominal aortic aneurysms, where additional techniques to preserve renal artery perfusion are required.

METHODS

Retrospective analysis of consecutive patients who underwent emergent and elective aortic repair with fenestrated PMEGs between March 2019 and January 2023. Endpoints were technical success, reinterventions, secondary reinterventions and target vessel patency.

RESULTS

Forty-seven target vessels in 37 patients (23 male, median age 75 years) were targeted, of which 44 were renal arteries (RAs) with a mean diameter of 5.4 ± 1.0 mm. Thirteen were accessory RAs and six had a diameter ≤ 4 mm. Technical success rate was 87% overall; 97% for main and 62% for accessory RAs respectively. Target vessel patency and freedom from secondary reintervention was 100% and 97% at 30 days and 96% and 91% at one year, respectively. There was no 30-day mortality.

CONCLUSION

Fenestrated physician-modified endografts are safe and effective for the treatment of patients with juxtarenal abdominal aortic aneurysms when incorporating main renal arteries. Limited technical success may be expected when targeting accessory renal arteries, especially when small in diameter. Long-term follow-up is needed to confirm durability of PMEGs for renal artery preservation.

Emergent endovascular treatment options for thoracoabdominal aortic aneurysm

For a long time, parallel grafting, physician-modified endografts, and, more recently, in situ fenestration were the only go-to endovascular options for ruptured thoracoabdominal aortic aneurysm, offered mixed results, and depended mainly on the operator's and center's experience. As custom-made devices have become an established endovascular treatment option for elective thoracoabdominal aortic aneurysm, they are not a viable option in the emergency setting, as endograft production can take up to 4 months. The development of off-the-shelf (OTS) multibranched devices with a standardized configuration has allowed the treatment of ruptured thoracoabdominal aortic aneurysm with emergent branched endovascular procedures. The Zenith t-Branch device (Cook Medical) was the first readily available graft outside the United States to receive the CE mark (in 2012) and is currently the most studied device for those indications. A new device, the E-nside thoracoabdominal branch endoprosthesis OTS multibranched endograft (Artivion), has been made commercially available, and the GORE EXCLUDER thoracoabdominal branch endoprosthesis OTS multibranched endograft (W. L. Gore and Associates) is expected to be released in 2023. Due to the lack of guidelines on ruptured thoracoabdominal aortic aneurysm, this review summarizes the available treatment options (ie, parallel grafts, physician-modified endografts, in situ fenestrations, and OTS multibranched devices), compares the indications and contraindications, and points out the evidence gaps that should be filled in the next decade.

Five-year outcomes of physician-modified endografts for repair of complex abdominal and thoracoabdominal aortic aneurysms

OBJECTIVE

There is paucity of data on the durability of physician modified endografts (PMEGs) for complex abdominal (CAAAs) and thoracoabdominal aortic aneurysms (TAAAs) despite widespread use. The aim of this study was to evaluate and compare the early and long-term outcomes of fenestrated-branched endovascular aortic repair (FB-EVAR) for CAAAs and TAAAs using PMEGs.

METHODS

We reviewed clinical data and outcomes of patients treated by FB-EVAR using PMEGs for CAAAs (defined as short-neck infrarenal, juxtarenal, and pararenal AAAs) and TAAAs between 2007 and 2019. All patients were treated by a dedicated team with extensive manufactured device experience. Endpoints included 30-day mortality and major adverse events, patient survival and freedom from aortic-related mortality (ARM), freedom from secondary intervention, target artery (TA) patency, and freedom from TA endoleak and TA instability.

RESULTS

Of 645 patients undergoing FB-EVAR, 156 patients (24%) treated with PMEG (121 males; mean age, 75 ± 8 years) were included. There were 89 CAAAs, 33 extent IV TAAAs and 34 extent I to III TAAAs. A total of 452 renal-mesenteric targets (3.1 ± 1.0 vessels/patient) were incorporated. Patients with TAAAs had significantly (P < .05) larger aneurysms (73 ± 11 vs 68 ± 14 mm), more TAs incorporated (3.4 ± 0.9 vs 2.8 ± 1.0), and more often had previous aortic repair (54% vs 27%). Technical success was higher in patients treated for CAAAs (99% vs 91%; P = .04). Thirty-day and/or in-hospital mortality was 5.7% and was significantly lower for CAAAs compared with TAAAs (2% vs 10%; P = .04), with three of nine early mortalities (33%) among patients treated emergently. After a mean follow-up of 49 ± 38 months, there were 12 aortic-related deaths (7.6%), including nine early deaths (5.7%) from perioperative complications and three late deaths (1.9%) from rupture. At 5 years, patient survival was 41%. Patients treated for CAAAs had higher 5-year freedom from ARM (P = .016), TA instability (P = .05), TA endoleak (P = .01), and TA secondary interventions (P = .05) with a higher, but non-significant, freedom from sac enlargement ≥5 mm (P = .11). Primary and secondary TA patency was 91% ± 2% and 99% ± 1%, respectively. Sac regression ≥5 mm occurred in 67 patients (43%) and was associated with increased survival (hazard ratio, 0.54; 95% confidence interval, 0.37-0.80) compared with those without sac regression.

CONCLUSIONS

FB-EVAR using PMEGs was performed with acceptable long-term outcomes. Overall patient survival was low due to significant underlying comorbidities. Patients treated for CAAAs had higher freedom from ARM, TA instability, TA endoleak, TA secondary interventions, and a trend towards higher freedom from sac enlargement compared with patients treated for TAAAs. Sac regression was associated with improved patient survival.

Thoracoabdominal Aortic Disease and Repair: JACC Focus Seminar, Part 3

Thoracoabdominal aortic disease is a rare but life-threatening condition that requires expert multidisciplinary collaborative management. Intervention is indicated in patients with symptomatic aneurysms or when an aneurysm reaches a certain threshold of diameter or rate of expansion. The strategies for spinal cord and end-organ protection have evolved over several decades, resulting in improved outcomes after repair. Open repair, although invasive, provides definitive and durable repair. Endovascular approaches are rapidly evolving, and the results with fenestrated and branched endografts are promising. Both open repair and endovascular repair require highly specialized expertise, and outcomes are best when repair is undertaken in an elective setting by a dedicated team. Patients with degenerative thoracoabdominal aortic aneurysms and chronic dissections should be followed up closely and referred for elective repair when indicated.

Systematic Review and Meta-analysis of Physician Modified Endografts for Treatment of Thoraco-Abdominal and Complex Abdominal Aortic Aneurysms

OBJECTIVE

Perform a systematic review and meta-analysis of the outcomes of physician modified endografts (PMEG) for treatment of thoraco-abdominal (TAAA) and complex abdominal aortic aneurysm (C-AAA) repair.

METHODS

We searched MEDLINE, CENTRAL, Web of Science Core Collection, Scielo and Open Grey databases from inception to July 2021 for studies reporting on outcomes of PMEGs for TAAA or C-AAA repair. A systematic review was conducted (protocol CRD42021267856) and data were pooled using a random-effects model of proportions. The outcomes analyzed were major adverse events at 30-days [30-day mortality, myocardial infarction, respiratory failure requiring prolonged ventilation (>24h or re-intubation), renal failure requiring dialysis, bowel ischemia requiring surgery, major stroke or definitive paraplegia]; technical success; 30-day mortality; ruptures; spinal cord ischemia; endoleaks; re-interventions and target vessel patency.

RESULTS

Twenty studies were included. Overall study quality assessment was found to be low. Overall, 909 PMEGs were reported and analyzed. Regarding aneurysm location (n=867), 222 patients had extent I-III TAAAs and 645 had C-AAA or extent IV TAAA. Regarding presentation, 14 studies reported if the patients were treated in an elective or urgent setting (n=782 patients). Overall, 500 (63.9%) patients were treated in an elective setting and 282(36.1%) in an urgent setting. Major adverse events (at thirty-days) occurred in 15.5% of patients (95%CI:10.8;20.8;I²=63%,135/832cases), being 11.6%(95%CI:8.1;15.7;I²=0%,23/280 cases) for elective patients and 24.6% for urgent (95%CI:14.1;36.6;I²=65%,50/192cases). Overall technical success was 97.2%(95%CI:95.4;98.7;I²=0%,587/611cases), being 98.0%(95%CI:92.1;100;I²=0%,106/113cases) for extent I-III TAAAs and 99.4%(95%CI:97.5;100;I²=0%,317/324cases) for C-AAA and extent IV TAAAs. Regarding technique, technical success was 96.1% for FEVAR (95%CI:93.2;98.4;I²=0%,313/329cases) and 99.8% for F/B-EVAR (95%CI:99.8;100;I²=0%,17/18 cases).

CONCLUSION

Physician modified fenestrated or branched grafts for endovascular aortic repair seems feasible and safe in the short-term follow-up. However, the quality of the available data is low which highlights the need for better and more accurate data regarding this technique.

Outcomes of off-the-shelf multibranched stent grafts with intentional occlusion of directional branches using endovascular plugs during endovascular repair of complex aortic aneurysms

OBJECTIVE

To evaluate the technique and outcomes of intentional occlusion of directional branches (DBs) using endovascular plugs during branched endovascular aortic repair using off-the-shelf Zenith t-Branch thoracoabdominal (TAAA) stent grafts.

METHODS

We reviewed the clinical data and outcomes of all consecutive patients treated by branched endovascular aortic repair using off-the-shelf Zenith t-Branch TAAA stent-graft (Cook Medical, Bloomington, Ind) in seven academic centers from 2013 to 2019. All patients had at least one DB intentionally occluded using extension of the branch with balloon or self-expandable covered stent, followed by placement of endovascular plugs. Intentional occlusion was indicated in patients with variations in the normal four-vessel renal-mesenteric anatomy, pre-existing dialysis, or in those who failed catheterization of a target vessel. End points were 30-day/in-hospital mortality, major adverse events, secondary interventions, target artery (TA) patency, TA instability, and patient survival.

RESULTS

There were 100 patients, 65 male and 35 female, with median age of 71 years (interquartile range [IQR], 66-75 years). Of these, 31 patients (31%) had urgent/emergent operations for symptomatic/contained ruptured aneurysms. The median aneurysm diameter was 72 mm (IQR, 61-85 mm). A total of 290 renal-mesenteric arteries were incorporated with a median of three (IQR, 3-3) vessels/patient. Indications for DB occlusion were less than four suitable renal-mesenteric targets in 84 patients or pre-existing dialysis and inability to catheterize a target vessel in eight patients each. There were 110 DBs occluded by vascular plugs, including 48 celiac axis, one superior mesenteric artery, and 61 renal DBs. Thirty-day/in-hospital mortality was 10%, including 9% for elective and 13% for urgent/emergent procedures. Major adverse events occurred in 44 patients (44%), including acute kidney injury in 19 patients (19%), estimated blood loss >1 L in 12 patients (12%), respiratory failure and new onset dialysis in six patients (6%) each, bowel ischemia in five patients (5%), and myocardial infarction and paraplegia in two patients (2%) each. The median follow-up was 5 months (range, 1-13 months). Eighteen patients (18%) required secondary interventions, none for problems related to the occluded DB. There were no endoleaks related to the occluded DB. At 2 years, primary and secondary patency and freedom from TA instability were 93% ± 3%, 97% ± 2%, and 91% ± 4%, respectively. Freedom from secondary interventions and patient survival were 75% ± 6% and 63% ± 7%, respectively.

CONCLUSIONS

Intentional occlusion of DBs using endovascular plugs allows versatile use of a four-vessel off-the-shelf multi-branched TAAA stent graft in patients with variations in the normal renal and mesenteric anatomy or when technical difficulties prevent successful target vessel stenting. There were no endoleaks or secondary interventions associated with the occluded DB.

Physician-modified endografts are associated with a survival benefit over parallel grafting in thoracoabdominal aneurysms

OBJECTIVE

Physician-modified endografts (PMEG) and parallel grafting (PG) are important techniques for endovascular repair of complex aortic aneurysms using off-the-shelf devices. However, there is little data regarding the relative efficacy and outcomes of these techniques in thoracoabdominal extent aneurysms. This study sought to compare outcomes of PG and PMEG across different extents of thoracoabdominal aneurysms to which they can be employed.

METHODS

The SVS VQI TEVAR/Complex EVAR module was queried for all patients undergoing repair of an unruptured, thoracoabdominal aneurysm (TAAA, Extents I-IV) years 2012-2020; aneurysm types were defined by repair extent as determined by proximal and distal seal zones. Patients were differentiated based on whether they received repair with a physician-modified endograft (PMEG) or parallel grafting technique (PG). The primary outcomes for this study were overall survival and freedom from aneurysm/procedure-related mortality at 1-year determined via Kaplan-Meier analysis, with Cox hazard regression analysis conducted to examine the independent association of repair modality with primary outcomes.

RESULTS

813 patients met inclusion criteria (TAAA I-III 362, TAAA IV 451; 426 PG, 387 PMEG). PMEG repairs were performed at centers with a nearly 2-3-fold higher annual volume of endovascular TAAA repairs. Type Ia endoleaks were reduced with PMEG repair, most significantly in TAAA IV (TAAA I-III: 2.2% PMEG vs. 10% PG, p = 0.2; TAAA IV: 1.2% PMEG vs. 21.6% PG, p <0.001). Thoracoabdominal repairs demonstrated improved survival at 1-year with PMEG devices, significant for TAAA I-III repairs (TAAA I-III: PMEG 85% vs. PG 74%, p = 0.01; TAAA IV: 84% PMEG vs. PG 78%, p = 0.08). Freedom from aneurysm/procedure-related mortality was also improved with PMEG repairs, remaining significant at 1-year in the case of TAAA IV (TAAA I-III: PMEG 94% vs. PG 86%, p = 0.06; TAAA IV: PMEG 94% vs. PG 88%, p = 0.02). PMEG demonstrated reductions in several measures of post-operative morbidity, including stroke/death, MACE, and post-operative complications. In multivariate analysis, repair modality was not associated with either primary outcome, rather, several perioperative complications conveyed the greatest hazard for both primary outcomes across repair extents.

CONCLUSIONS

Survival after endovascular TAAA repair is improved with the use of PMEG compared to PG. Several key factors of this study demonstrate the shortcomings of parallel grafting in complex aneurysm repair, namely high rates of critical endoleaks, the need for adjunctive access sites, and an increase in perioperative complications that influence longer-term outcomes.

Early and mid-term durability of surgeon-modified and custom-made fenestrated devices for the treatment of complex aortic pathology

OBJECTIVE

Fenestrated endovascular aneurysm repair (F-EVAR) has allowed successful treatment of patients with complex aortic aneurysms. Custom-made devices (CMDs) are manufactured by companies and tailored to the patient's anatomy to incorporate target vessels, while there is also the "off label" alternative with the devices modified by a surgeon in the operating room: surgeon-modified FEVAR (sm-FEVAR). This study aims to present and compare technical durability of CMDs- and sm-FEVAR for complex abdominal and thoracoabdominal aortic pathologies.

METHODS

A retrospective cohort study was undertaken including all consecutive patients treated with sm- or CMD-FEVAR during a 3-year period in a single centre. Only cases with at least three reno-visceral target vessels were included. Primary outcomes were technical success, and freedom from endoleak (EL) (Ia or III; all branch related) and re-intervention during follow-up period. Mortality and morbidity were also recorded.

RESULTS

32 sm-FEVAR patients (81,3% male) and 79 CMD-FEVAR patients (77,2% male) were included. Indication for sm-FEVAR was exclusively urgent, while all CMD- FEVAR were elective. Technical success was similar in sm-FEVAR (100%) and CMD-FEVAR (98,7%) (p=0.523). Mean follow-up was 16.3±13 and 20±17.3 months for sm-FEVAR and CMD- FEVAR, respectively (p=0.28). The freedom from EL Ia rate was 91.7% [standard error (SE) 5.7%] at 12 months in sm-FEVAR, while it was 97.7% (SE 2.2%) and 92.3% (SE 4.3%) at 12 and 24 months, respectively in CMD-FEVAR (p=0.69). The freedom from EL III rate was 95.5% (SE 4.4%) and 88% (SE 8.2%) at 12 and 24 months, respectively in sm-FEVAR, while it was 92.1% (SE 3.8%) and 89.2% (SE 4.7%) at 12 and 24 months, respectively in CMD-FEVAR (p=0.68). The freedom from re-intervention rate was 91.6% (SE 5.7%) and 84.6% (SE 8.6%) at 12 and 24 months, respectively in sm-FEVAR, while it was 91.7% (SE 4%) and 83.4% (SE 5.9%) at 12 and 24 months, respectively in CMD-FEVAR (p=0.90). The survival rate was 87.5% (5.8%) and 76.3% (7.9%) at 1 and 12 months, respectively in sm-FEVAR, while it was 93.7% (2.7%) at 1 month in CMD-FEVAR without any other death during FU period. No bridging stent occlusions were noted during follow up period in any patient.

CONCLUSION

Sm-FEVAR offers good technical success and mid-term clinical outcomes in urgent cases of complex aortic pathologies. Its durability is acceptable and comparable to CMD-FEVAR with a relatively low re-intervention rate.

Endovascular treatment of thoracoabdominal aortic aneurysms

Endovascular repair of thoracoabdominal aneurysms using fenestrated and/or branched stent grafts is technically feasible and efficacious but carries a steep learning curve. This innovative surgical approach is associated with less perioperative morbidity than traditional open repair and its early and mid-term outcomes are very favorable. Spinal cord ischemia remains a devastating complication after these procedures, hence the importance of various neuroprotective strategies. Widespread applicability remains limited in the United States, as no custom-made or off-the-shelf endografts are commercially available. Access to these devices remains limited to physician-sponsored or industry-sponsored clinical trials, but results from the Cook p-Branch and Gore Thoracoabdominal Branch Endoprosthesis trials are on the horizon.

Physician-modified endografts for urgent and emergent aortic pathology

Symptomatic or ruptured thoracoabdominal aortic aneurysms (TAAA) carry a high morbidity and mortality. Modern fenestrated and/or branched endovascular devices (B/FEVAR) have improved the immediate peri-operative mortality of TAAA and have increased the number of people that can undergo repair - in those who might otherwise be prohibitively high risk for surgery. Most modern B/FEVAR are custom made devices that require 6-12 weeks to assemble and ship to the site of implantation. Thus, patients who require more urgent repair due to symptomatic or ruptured aneurysms may not have access to this potentially life saving technology. Physician-modified endografts (PMEGs), or traditional endografts that have been back-table modified to have fenestrations or branches, have partially fixed this problem as they can be constructed in less than an hour and can provide similar results to modern custom made devices. Here we review the existing data behind the use of PMEGs in urgent and emergent aortic pathology and summarize a case describing one methodology for PMEG construction that has been standardized at our institution.

Custom-made fenestrated stent for mycotic aortic aneurysms: a report of two cases

Background

Mycotic aortic aneurysm is a rare and potentially life-threatening lesion, and endovascular repair has become increasingly accepted for intervention. Fenestrated endografts are available options to treat aneurysms involving visceral arteries. Here, we first report two patients with mycotic aortic aneurysm involving paraviscereal aorta who were successfully treated with custom-made fenestrated endograft.

Case presentation

Two patients were presented with mycotic aortic aneurysm. Due to their comorbidities and the involvement of the renal arteries, company-manufactured fenestrated stents were designed. Meanwhile, antibiotic therapy was administrated for 2 months before endovascular repair. Patients improved well without complications.

Conclusions

Custom-made fenestrated endovascular stent is an effective and feasible alternative solution to mycotic paravisceral aorta aneurysm.

Open repair versus evar with parallel grafts in patients with juxtarenal abdominal aortic aneurysm excluded from fenestrated endografting

BACKGROUND

We compared the outcomes of open surgical repair (OSR) versus EVAR with parallel graft technique (PG) in patients with juxtarenal abdominal aortic aneurysm (JAAA) excluded from fenestrated endovascular aortic repair (FEVAR) due to clinical, anatomical, technical or manufacturing time reasons.

METHODS

A single-center analysis of consecutive patients who underwent elective and urgent (within 24-48 hours) repair of JAAA from January 2010 to January 2019 was performed. Two groups were compared: patients excluded from FEVAR and respectively treated by OSR or by PG for JAAA. Perioperative clinical, anatomic and operative data were collected in a dedicated database. The endpoints were primary technical success, changes in renal function, early and long-term mortality, freedom from aortic related reinterventions (ARRs) and aortic related mortality (ARM).

RESULTS

118 consecutive patients were treated for JAAA, 32 of them (27.1%) with FEVAR. 86 patients were enrolled in the study (OSR group=61; PG group= 25). The mean age was 77.4 ± 6.5 years for PG group and 71.1 ± 6.7 years for OSR group (p=.0001); the average comorbidity score of the Society for Vascular Surgery was higher for patients treated by PG (10.2 ± 4.8 vs 5.5 ± 0.4, p=.0001), with no differences for hypertension and renal score. After propensity score matching, 42 patients (OSR=27 ; PG=15) without differences in the preoperative risk factors were selected. Conical shape and neck mural thrombus were respectively more represented in the OSR group (95.1% vs 56.0%; 63.9% vs 36.0%). Aortic clamp site was supraceliac for 12 patients (19.7%), suprarenal for 21 (34.4%) and trans-renal for 28 patients (45.9%). In the PG group, 16 patients (64%) were treated with a single renal chimney. Primary technical success was similar in the two groups (100.0% vs 92.0%, p=.08), with an higher rate of procedure achieved by assisted technical success for the PG group after propensity score matching analysis (20.0% vs 0%, p=.04). Deterioration of renal function occurred for both groups of patients, with a significant creatinine increasing 12 months after surgery in the PG group compared with OSR group (1.72 ± 0.66 vs 1.18 ± 0.40, p=.006). Multiple logistic regression shows no independent predictor of peri-operative medical complication among demographics and pre-operative relevant clinical factors between the two cohorts. No difference in terms of early mortality was observed between the groups (1.6 % vs 0%, p=1.00). At 5 years, overall survival was lower for patients treated by PG (53.5% vs 70.2%, p=.007), such as freedom from ARRs (64.6 vs 90.5%, p=.03). Freedom from ARM at 5 years did not show significant differences among the two groups (100% vs 98.4%, p=1.00).

CONCLUSIONS

PG represents a feasible procedure for patients excluded from FEVAR due to clinical, anatomical, technical or device manufacturing time reasons, ensuring low rates of ARM. However, ARRs during the follow-up remain the Achilles heel of this technique. OSR is still the most durable procedure in the endovascular era, allowing the treatment of proximal "hostile necks" with low rates of reoperation and a similar impact on the renal function compared to PG.

Clinical application and technical details of cook zenith devices modification to treat urgent and elective complex aortic aneurysms

Purpose

To describe technical details of modifying four different Cook Zenith devices to treat complex aortic aneurysms.

Material

In the first three cases, the modification process involved complete stent graft deployment on a sterile back table. Fenestrations were created using an ophthalmologic cautery and reinforced with a radiopaque snare using a double-armed 4–0 Ethibond locking suture based on measurements obtained on centerline of flow. In each instance, a nitinol wire was withdrawn and redirected through and through the fabric and used as a constraining wire. In the fourth patient, modification involved partial stent graft deployment and creation of additional two fenestrations to accommodate renal arteries. The devices are resheathed and implanted in the standard fashion.

Results

Four patients underwent exclusion of their aneurysms, including thoracoabdominal aneurysms (n = 2), a contained ruptured juxtarenal aneurysm (n = 1), and a ruptured failed previous endovascular repair (n = 1). Fifteen fenestrations were successfully bridged with Atrium iCAST stent grafts. Average graft modification time, operative time, contrast volume, radiation dose, estimated blood loss, and hospital length of stay were 89 min, 155.25 min, 58.8 mL, 2451 mGy, 175 mL, and 4.3 days, respectively. One patient required a secondary intervention to treat a type Ib endoleak. During an average follow-up of 25 months, aneurysm sacs progressively shrank without additional intervention.

Conclusion

Physician-modified fenestrated/branched endografts are a safe alternative to custom made devices, especially in urgent cases and should be part of the armamentarium of any complex aortic program.

Evolution of fenestrated/branched endovascular aortic aneurysm repair complexity and outcomes at an organized center for the treatment of complex aortic disease

BACKGROUND

Fenestrated/branched endovascular aneurysm repair (F/BEVAR) volume has increased rapidly, with favorable outcomes at centers of excellence. We evaluated changes over time in F/BEVAR complexity and associated outcomes at a single-center complex aortic disease program.

METHODS

Prospectively collected data of all F/BEVAR (definition: requiring ≥1 fenestration/branch), procedures performed in an institutional review board-approved registry and/or physician-sponsored investigational device exemption trial (IDE# G130210), were reviewed (11/2010-2/2019). Patients were stratified by surgery date into thirds: early experience, mid experience, and recent experience. Patient and operative characteristics, aneurysm morphology, device types, perioperative and midterm outcomes (survival, freedom from type I or III endoleak, target artery patency, freedom from reintervention), were compared across groups.

RESULTS

For 252 consecutive F/BEVARs (early experience, n = 84, mid experience, n = 84, recent experience, n = 84), 194 (77%) company-manufactured custom-made devices, 11 (4.4%) company-manufactured off-the-shelf devices, and 47 (19%) physician-modified devices, were used to treat 5 (2.0%) common iliac, 97 (39%) juxtarenal, 31 (12%) pararenal, 116 (46%) thoracoabdominal, and 2 (0.8%) arch aneurysms. All patients had follow-up for 30-day events. The mean follow-up time for the entire cohort was 589 days (interquartile range, 149-813 days). On 1-year Kaplan-Meier analysis, survival was 88%, freedom from type I or III endoleak was 91%, and target vessel patency was 92%. When stratified by time period, significant differences included aneurysm extent (thoracoabdominal, 33% early experience, 40% mid experience, and 64% recent experience; P < .001) and target vessels per case (four-vessel case, 31% early experience, 39% mid experience, and 67% recent experience; P < .0001). There was no difference, but a trend toward improvement, in composite 30-day events (early experience, 39%; mid experience, 23%; recent experience, 27%; P = .05). On Kaplan-Meier analysis, there was no difference in survival (P = .19) or target artery patency (P = .6). There were differences in freedom from reintervention (P < .01) and from type I or III endoleak (P = .02), with more reinterventions in the early experience, and more endoleaks in the recent period.

CONCLUSIONS

Despite increasing repair complexity, there has been no significant change in perioperative complications, overall survival, or target artery patency, with favorable outcomes overall. Type I or III endoleaks remain a significant limitation, with increased incidence as the number of branch arteries incorporated into the repairs has increased.

Effect of thoracoabdominal aortic aneurysm extent on outcomes in patients undergoing fenestrated/branched endovascular aneurysm repair

OBJECTIVE

The outcomes after open repair of thoracoabdominal aneurysms (TAAAs) have been definitively demonstrated to worsen as the TAAA extent increases. However, the effect of TAAA extent on fenestrated/branched endovascular aneurysm repair (F/BEVAR) outcomes is unclear. We investigated the differences in outcomes of F/BEVAR according to the TAAA extent.

METHODS

We reviewed a single-institution, prospectively maintained database of all F/BEVAR procedures performed in an institutional review board-approved registry and/or physician-sponsored Food and Drug Administration investigational device exemption trial (trial no. G130210). The patients were stratified into two groups: group 1, extensive (extent 1-3) TAAAs; and group 2, nonextensive (juxtarenal, pararenal, and extent 4-5) TAAAs. The perioperative outcomes were compared using the χ² test. Kaplan-Meier analysis of 3-year survival, target artery patency, reintervention, type I or III endoleak, and branch instability (type Ic or III endoleak, loss of branch patency, target vessel stenosis >50%) was performed. Cox proportional hazards modeling was used to assess the independent effect of extensive TAAA on 1-year mortality.

RESULTS

During the study period, 299 F/BEVAR procedures were performed for 87 extensive TAAAs (29%) and 212 nonextensive TAAAs (71%). Most repairs had used company-manufactured, custom-made devices (n = 241; 81%). Between the two groups, no perioperative differences were observed in myocardial infarction, stroke, acute kidney injury, dialysis, target artery occlusion, access site complication, or type I or III endoleak (P > .05 for all). The incidence of perioperative paraparesis was greater in the extensive TAAA group (8.1% vs 0.5%; P = .001). However, the incidence of long-term paralysis was equivalent (2.3% vs 0.5%; P = .20), with nearly all patients with paraparesis regaining ambulatory function. On Kaplan-Meier analysis, no differences in survival, target artery patency, or freedom from reintervention were observed at 3 years (P > .05 for all). Freedom from type I or III endoleak (P < .01) and freedom from branch instability (P < .01) were significantly worse in the extensive TAAA group. Cox proportional hazards modeling demonstrated that F/BEVAR for extensive TAAA was not associated with 1-year mortality (hazard ratio, 1.71; 95% confidence interval, 0.91-3.52; P = .13).

CONCLUSIONS

Unlike open TAAA repair, the F/BEVAR outcomes were similar for extensive and nonextensive TAAAs. The differences in perioperative paraparesis, branch instability, and type I or III endoleak likely resulted from the increasing length of aortic coverage and number of target arteries involved. These findings suggest that high-volume centers performing F/BEVAR should expect comparable outcomes for extensive and nonextensive TAAA repair.

Comprehensive Review of Physician Modified Aortic Stent Grafts: Technical and Clinical Outcomes

OBJECTIVE

Physician modified stent grafts (PMSGs) present satisfactory results in selected cases of complex aortic pathologies. However, the technique lacks standardisation and depends on the surgeon and aortic segment. The aim of this article is to review comprehensively the technical details and clinical results of PMSGs related to patients with pathology in all aortic locations.

METHODS

A MEDLINE search (last search 20 April 2020) identified 20 relevant papers in the English language published over the last 20 years evaluating clinical outcomes after a PMSG and specifying the technical details to design it.

RESULTS

Seven hundred and eleven patients were included in the analyses, with 59% being operated on as an emergency. Ninety-two per cent of abdominal aortic segment PMSGs (A-PMSGs) were performed either as an emergency or before 2012. The main indications were available in 670 cases; 435 were degenerative aneurysms (64.9%) and 171 were aortic dissections (25.5%). Most of the endografts used were composed of polyethylene terephthalate, except for the Ankura (expanded polytetrafluoroethylene [Lifetech Scientific, Shenzhen, China]; n = 50, 7.5%). The Valiant (Medtronic, Minneapolis, MN, USA) represented 65% (n = 169) of aortic arch PMSGs (aa-PMSGs) and the Zenith platform (Cook Medical, Bloomington, IN, USA) 51% (n = 139) of A-PMSGs. A snare was used to reinforce the fenestration in 458 PMSGs (66%) and a cautery device cut the fenestration in 484 (75%) PMSGs. No bridging stent was used in 47 (7.0%) PMSGs (these aa-PMSGs had large fenestrations). Technical success ranged from 87.5% to 100% and 30 day mortality from 0% to 8%. Primary branch patency ranged from 96.3% to 100% at 12 month follow up. Zero to 14% of patients experienced type 3 or type 1 endoleak at 14.8 month follow up.

CONCLUSION

PMSG is a useful technique, particularly when validated treatments are not available. However, it is a non-standardised technique and the long term consequences of modifications remain unknown.

Use of 3D Printing to Guide Creation of Fenestrations in Physician-Modified Stent-Grafts for Treatment of Thoracoabdominal Aortic Disease

Purpose: To summarize the experience and outcomes of total endovascular repair of thoracoabdominal aortic disease using 3-dimensional (3D) printed models to guide on-site creation of fenestrations in aortic stent-grafts. Materials and Methods: From April 2018 to March 2019, 34 patients (mean age 58±14 years; 24 men) with thoracoabdominal aortic disease were treated in our department. Nineteen patients had thoracoabdominal aortic dissection and 15 had thoracoabdominal aortic aneurysm. Preoperatively, a 3D printed model of the aorta was made according to computed tomography images. In the operating room, the main aortic stent-graft was completely released in the 3D printed model, and the position of each fenestration or branch was marked on the stent-graft. The fenestrations were then made using an electric pen. Wires were sewn to the edge of the fenestrations using nonabsorbable sutures. After customization, the aortic stent-graft was reloaded into the delivery sheath and deployed. Results: The printing process took ~5 hours (1 hour for image reconstruction, 3 hours for printing, and 1 hour for postprocessing). The physician-modified stent-grafts had a total of 107 fenestrations secured by 102 bridging stent-grafts, including 73 covered stents and 29 bare stents. The average procedure time was 5.6±1.2 hours, including a mean 1.3 hours for stent-graft customization. No renal insufficiency or paraplegia occurred. Two branch arteries were lost during the operation. One patient (3%) died 1 week after surgery from a retrograde dissection rupture. One patient developed a minor cerebral infarction postoperatively. The mean follow-up time was 8.5 months. There was 1 endoleak from a fenestration (coil embolized) and 4 distal ruptures of the aortic dissection (3 treated and 1 observed). Conclusion: Three-dimensional printing can be used to guide creation of fenestrated stent-grafts for the treatment of thoracoabdominal aortic diseases involving crucial branches. This technique appears to be more accurate than the traditional measurement method, with short-term follow-up demonstrating the safety and reliability of the method. However, further research and development are needed.

Physician-Modified Endovascular Gore Excluder Graft (Handmade Modified) for Complex Abdominal Aortic Aneurysm: A Step-by-Step Approach

Endovascular repair has become the gold standard for the treatment of infrarenal abdominal aortic aneurysmal disease. Branched and fenestrated commercially custom-made devices have been developed as a treatment option for short necks or juxtarenal aneurysms. However, the lack of availability in some countries and centers, manufacturing time (6-8 weeks requirements), urgent setting in ruptured abdominal aortic aneurysms, and elevated costs make them not a widespread option. Hereby, we expose our step-by-step technique of physician modified Gore Excluder  to treat complex aneurysms. Physician-modified endovascular graft (PMEG) has emerged as an alternative to open repair for the treatment of complex aortic aneurysms. The ultimate goal of fenestrations is to increase the proximal sealing zone length. The Gore C3 delivery system allows repositioning of the graft by constraining the proximal part after a back-table physician modification; the PMEG technique with the Gore Excluder C3 delivery system can be used for complex aortic aneurysms repair as an alternative treatment option.

The role of fEVAR, chEVAR and open repair in treatment of juxtarenal aneurysms: a systematic review

INTRODUCTION

Open repair (OR), fenestrated endovascular aneurysm repair (fEVAR) and endovascular exclusion using parallel graft (chEVAR) are complementary procedures used for treatment of juxtarenal abdominal aortic aneurysm (jrAAA). The aim of our study was to assess available literature and analyze dispersion of OR, fEVAR and chEVAR procedures among reported papers related to treatment of jrAAA.

EVIDENCE ACQUISITION

The PubMed database was systematically searched using predefined strategy and key words related to treatment of jrAAA on September 28th, 2019. Studies were assessed for eligibility using the inclusion and exclusion criteria with at least five patients treated with at least one of the procedures while systematic reviews, meta-analysis, reviews, comments, editorials and letters were excluded as well as studies without clear classification of the location of the aneurysm, studies not specifying the number of patients treated with each of the techniques or not discriminated between aortic pathologies (juxtarenal, paravisceral and thoracoabdominal), hybrid procedures, endoanchors or with branched stent-graft.

EVIDENCE SYNTHESIS

Overall, 1533 papers were identified while papers that met inclusion criteria were either representing experience of single institution (87 papers) or from multicenter studies (6 papers), national or international registries (18 papers). In the period between January 1977 and December 2017, treatment of 5664 patients with jrAAA was reported in 87 papers as a single institution report. Out of them 2531 (45%) were treated with OR, 2592 (46%) with fEVAR and 541 (9%) with chEVAR. Out of 29 institutions reporting OR, there were 11 (37.9%) with more than 100 treated patients while 21 (41.1%) out of 51 institutions that reported more than 50 jrAAA treated with fEVAR. Only four institutions reported results of all three treatment modalities.

CONCLUSIONS

Based on the results reported in the literature, regardless of its complexity and costs, fEVAR for jrAAA has been accepted in substantial number of hospitals worldwide, while number of reported procedures is reaching OR.

Acute Kidney Injury after Complex Endovascular Aneurysm Repair

Background:

Complex endovascular repair of abdominal aortic aneurysm carries higher perioperative morbidity than standard infrarenal endovascular repair.

Objective:

This study reviews the incidence and associated factors of acute kidney injury in complex aortic endovascular repair of juxtarenal, pararenal, and thoracoabdominal aortic aneurysms.

Methods:

A literature review was performed for all studies on the endovascular repair of juxtarenal, pararenal, and thoracoabdominal aneurysms that evaluated rates of acute kidney injury as an outcome. Outcomes were further analyzed by the level of anatomic complexity and method of repair.

Results:

52 studies met inclusion criteria, with a total of 5454 individuals undergoing repair from 2004 to 2017. The overall rate of acute kidney injury ranged widely from 0 to 41%, with a rate of hemodialysis from 0 to 19% (temporary) and 0 to 14% (permanent). Increasing anatomic complexity was associated with higher rates of acute kidney injury. Mode of endovascular repair, learning curve effect, and preoperative chronic renal insufficiency did not demonstrate any associations with the outcome.

Conclusion:

Published rates of acute kidney injury in complex aortic aneurysm repair vary widely with few definitively associated factors other than increasing anatomic complexity and operative time. Further study is needed for the identification of predictors related to postoperative acute kidney injury.

Three-dimensional printing-guided fenestrated endovascular aortic aneurysm repair using open source software and physician-modified devices

Fenestrated endovascular aneurysm repair is frequently used for juxtarenal and pararenal aortic aneurysms. In urgent cases, however, the use of premanufactured patient-specific devices is not an option. Physician-modified endografts may be used to treat these patients but require experience and a steep learning curve for accurate planning to position fenestrations and to perform the graft modifications. Despite experience, a margin of error in placing fenestrations always exists, and a mismatch possibility between the fenestration and vessel ostium can lead to increased cannulation time and stent complications, including target vessel loss. Aortic three-dimensional printing has been widely described in medicine for simulation, training, and surgical planning. Commercial software is currently under investigation for planning of fenestrated endovascular aneurysm repair at high costs. We describe an effective and inexpensive technique using free computer-aided design software to create a real 1:1 aortic 3D model that can easily be printed and quickly sterilized. This aortic model can be used to create a physician-modified endograft and to place fenestrations in an accurate way, with potential for shorter and more precise procedures and better long-term results. Two cases are presented to illustrate the technique, demonstrating that 3D printing is a valuable tool to plan, design, and create fenestrated devices more accurately.

Intraoperative adverse events and early outcomes of custom-made fenestrated stent grafts and physician-modified stent grafts for complex aortic aneurysms

OBJECTIVE

Physician-modified fenestrated stent grafts (PMSGs) are a useful option for urgent or semiurgent treatment of complex abdominal aortic aneurysms (CAAAs). The aim of this study was to describe in-hospital outcomes of custom-made fenestrated stent grafts (CMSGs) and PMSGs for the treatment of CAAAs and thoracoabdominal aortic aneurysms (TAAAs).

METHODS

In this single-center, retrospective study, all consecutives patients with CAAAs or TAAAs undergoing endovascular repair using Zenith CMSGs (Cook Medical, Bloomington, Ind) or PMSGs between January 2012 and November 2017 were included. End points were intraoperative adverse events, in-hospital mortality, postoperative complications, reinterventions, target vessel patency, and endoleaks.

RESULTS

Ninety-seven patients were included (CMSGs, n = 69; PMSGs, n = 28). The PMSG group included more patients assigned to American Society of Anesthesiologists class 4 (n = 14 [50%] vs n = 16 [23%]; P = .006) and more TAAAs (n = 17 [61%] vs n = 10 [15%]; P < .0001). Intraoperative adverse events were recorded in eight (11%) patients in the CMSG group vs six (21%) patients in the PMSG group. No intraoperative death or open conversion occurred. In-hospital mortality rates were of 4% (n = 3) in the CMSG group and 14% in the PMSG group (n = 4). Chronic renal failure was an independent preoperative risk factor of postoperative death or complications (odds ratio, 4.88; 95% confidence interval, 1.65-14.43; P = .004). Rates of postoperative complications were 22% (n = 15) and 25% (n = 7) in the CMSG and PMSG groups. Spinal cord ischemia rates were 4% (n = 3) and 7% (n = 2) in the CMSG and PMSG groups. Reintervention rates were 16% (n = 11) in the CMSG group and 32% (n = 9) in the PMSG group. At discharge, target vessel patency rate in CMSGs was 98% (n = 207/210). All target vessels (n = 98) were patent in the PMSG group. Endoleaks at discharge were observed in 24% of the CMSG group (n = 16) vs 8% of the PMSG group (n = 2).

CONCLUSIONS

Our study showed clinically relevant differences of several important in-hospital outcomes in the CMSG and PMSG groups. Larger cohorts and longer follow-up are needed to allow direct comparison. PMSGs may offer acceptable in-hospital results in patients requiring urgent interventions when CMSGs are not available or possible.

Midterm Results of Endovascular Treatment for the Patients with Thoracoabdominal Aortic Aneurysms

Treatment of thoracoabdominal aortic aneurysm (TAAA) remains a challenging pathology. Technologies and innovations of endovascular treatment, in particular the evolution of fenestrated and branched stent graft for complex aortic pathologies such as TAAA have provided excellent short-term results. However, the mid-term and long-term results of endovascular treatment for TAAA including endoleaks and branch patency are still unclear. This article provides an overview of available devices and results of endovascular treatment for TAAAs. (This is a translation of Jpn J Vasc Surg 2019; 28: 67–74.)

Evolution from physician-modified to company-manufactured fenestrated-branched endografts to treat pararenal and thoracoabdominal aortic aneurysms

OBJECTIVE

The purpose of this study was to review treatment trends and outcomes of patients who underwent fenestrated-branched endovascular aneurysm repair (F-BEVAR) of pararenal aneurysms (PRAs) or thoracoabdominal aortic aneurysms (TAAAs) using physician-modified endografts (PMEGs) or company-manufactured devices (CMDs).

METHODS

We reviewed the clinical data of 316 consecutive patients (242 male patients; mean age, 75 ± 8 years) who underwent F-BEVAR between 2007 and 2016. F-BEVAR was performed under two prospective investigational device exemption protocols since 2013. End points were mortality, major adverse events (MAEs), patient survival, reintervention, branch instability, aneurysm-related mortality, renal function deterioration, and target vessel patency.

RESULTS

There were 145 patients (46%) treated by PMEGs (84 PRAs, 26 extent IV and 35 extent I-III TAAAs) and 171 patients (54%) who had CMDs (88 PRAs, 42 extent IV and 41 extent I-III TAAAs). Choice of endograft evolved from PMEGs in 131 patients (83%) treated in the first half of experience to CMDs in 144 patients (91%) treated in the second half of experience (P < .001). Patients treated by PMEGs had significantly (P < .05) larger aneurysms, more chronic pulmonary and kidney disease, and higher comorbidity severity scores. A total of 1081 renal-mesenteric arteries were targeted in both groups. Technical success was lower for PMEGs (98% vs 99.5%; P = .02). Thirty-day mortality was 5.5% for PMEGs (PRAs, 1.2%; extent IV 3.8% and extent I-III, 17.1%) and 0% for CMDs (P = .0018). Patients treated by PMEGs had significantly more (P < .001) MAEs (48% vs 23%) and longer hospital stay (9 ± 10 days vs 6 ± 6 days; P = .001). Mean follow-up was significantly longer for patients treated by PMEGs (38 ± 26 months vs 14 ± 12 months; P < .001). At 3 years, patient survival (68% ± 4% vs 67% ± 8%; P = .11), freedom from reintervention (68% ± 4% vs 68% ± 8%; P = .17), primary (94% ± 2% vs 92% ± 2%; P = .64) and secondary target vessel patency (98% ± 1% vs 98% ± 1%; P = .89), and freedom from renal function deterioration (75% ± 4% vs 65% ± 6%; P = .24) were similar for patients treated by PMEGs or CMDs, respectively.

CONCLUSIONS

Choice of F-BEVAR evolved from PMEGs to almost exclusively CMDs under physician-sponsored investigational device exemption protocols. PMEG patients had more comorbidities and larger aneurysms. CMDs were performed with higher technical success, no mortality, and fewer MAEs.