Thromboembolic Complications after Zenith® Low Profile Endovascular Graft for Infrarenal Abdominal Aneurysms

Early Clinical Results From the Japanese Prospective Multicenter Study to Evaluate Zenith Alpha Abdominal Stent Graft for Abdominal Aortic Aneurysm (JUSTICE) Registry Demonstrate Acceptable Limb Patency at 12 Months

PURPOSE

Recent reports of the Zenith Alpha abdominal endovascular graft (Zenith Alpha AAA, Cook, Inc., Bloomington, Indiana) have demonstrated an unexpectedly high incidence of limb graft occlusion (LGO). The purpose of this study was to prospectively evaluate the performance of the Zenith AAA in Japan, with a specific focus on LGO.

MATERIALS AND METHODS

All endovascular aneurysm repairs (EVARs) for abdominal aortic aneurysms performed using the Zenith Alpha AAA from July 2020 to October 2021 in 23 Japanese hospitals were prospectively evaluated. All computed tomographic images were analyzed in the core laboratory. Late complications were defined as any aneurysm-related events occurring >30 days after EVAR, including aneurysm sac enlargement of >5 mm and any reinterventions performed. Endoleaks without sac enlargement or reintervention were excluded as late complications.

RESULTS

During the study period, 147 EVARs were performed using the Zenith Alpha AAA. The mean patient age was 76.5±7.7 years, 84.4% of patients were male, and the mean aneurysm diameter was 52.4±9.2 mm. Instruction-for-use violations were observed in 76 patients (51.7%), primarily associated with a severely angulated proximal neck (>60°). There were six intraoperative complications and 62 additional intraoperative treatments reported, most of which involved preemptive coil embolization of the inferior mesenteric artery (37 cases). Technical success, defined as the absence of type 1 or 3 endoleaks on final angiography, was achieved in 99.3% of patients. At 12 months, there was only one case of type 1/3 endoleak (0.8%) and one aneurysm sac enlargement exceeding 5 mm (0.8%); however, a high incidence of type 2 endoleaks was observed in 35.2% of patients, and aneurysm sac regression exceeding 5 mm was achieved in 30.1% of patients. Nine late complications were observed, and the rate of freedom from late complications at 12 months was 93.5%, encompassing four LGOs and one limb graft stenosis (3.4%).

CONCLUSIONS

In contrast to recent reports, our Japanese multicenter prospective study demonstrated satisfactory early clinical results, including an acceptable LGO rate, for the low-profile Zenith Alpha AAA. Long-term follow-ups will be performed to confirm the persistence of these outcomes.

CLINICAL IMPACT

This study prospectively evaluated the performance of 147 Zenith Alpha AAAs used for endovascular aneurysm repair with core-lab adjudication focusing especially on limb graft occlusion (LGO). At 12 months, aneurysm sac regression exceeding 5 mm was achieved in 30.1% of patients, and there was only one type 1/3 endoleak, one aneurysm sac enlargement (>5 mm), and nine late complications including five LGOs (3.4%), resulting in rate of freedom from late complications at 93.5%. Satisfactory early clinical results, including an acceptable rate of LGO can be achieved, particularly with cautious usage of the Zenith Alpha Spiral-Z Endovascular Leg." 5mm), and nine late complications including five LGOs (3.4%), resulting in rate of freedom from late complications at 93.5%. Satisfactory early clinical results, including an acceptable rate of LGO can be achieved, particularly with cautious usage of the Zenith Alpha Spiral-Z Endovascular Leg.

Clinical Performance of the Low Profile Zenith Alpha Abdominal Endovascular Graft: 2 Year Results from the ZEPHYR Registry

OBJECTIVE

The midterm outcomes of the low profile Zenith Alpha Abdominal Endovascular Graft from the ZEnith alPHa for aneurYsm Repair (ZEPHYR) registry are reported.

METHODS

The ZEPHYR registry is a physician initiated, multicentre, non-randomised, core laboratory controlled, prospective registry. Inclusion criteria were patients with a non-ruptured abdominal aortic aneurysm with a maximum diameter ≥ 50 mm or enlargement > 5 mm within 6 months, with a site reported infrarenal neck length of ≥ 10 mm and with the intention to electively implant the Zenith Alpha abdominal endograft. Patients from 14 sites across Germany, Belgium, and the Netherlands were included. The primary endpoint was treatment success, defined as technical success and clinical success. Technical success was defined as successful delivery and deployment of the endograft in the planned position without unintentional coverage of internal iliac or renal arteries, with successful removal of the delivery system. Clinical success was defined as freedom from aneurysm sac expansion > 5 mm, type I or type III endoleaks, aneurysm rupture, stent graft migration > 10 mm, open conversion, and stent graft occlusion.

RESULTS

Three hundred and forty-seven patients were included in the ZEPHYR registry. The median clinical follow up was 743 days (interquartile range [IQR] 657, 806) with a median imaging follow up of 725 days (IQR 408, 788). Treatment success at 6 months, 1, and 2 years was 92.5%, 90.4%, and 85.3%, respectively. Freedom from secondary intervention was 94.3%, 93.4%, and 86.9%, respectively. The predominant reason for secondary intervention was limb complications. Freedom from limb occlusion (per patient) at 6 months, 1, and 2 years was 97.2%, 95.8%, and 92.5%, respectively. Univariable and multivariable Cox regression analyses could not identify any independent predictor for limb complications.

CONCLUSION

While treatment success is comparable with other commercially available grafts, the rate of limb complications at 2 years is of concern. The manufacturer's instructions for use should be followed closely. Further studies are necessary to investigate the root cause of the increased rate of limb complications with the Zenith Alpha Abdominal Endovascular Graft.

Low profile endografts for the endovascular treatment of abdominal aortic aneurysms

INTRODUCTION

Favorable midterm outcomes have been reported with the use of low-profile endografts (LPE), but long-term data is still needed. Furthermore, it is unclear if each of these LPE may have advantages over the other, which may, in turn, affect the outcomes. We systematically reviewed the literature about complications and reintervention rates of patients submitted to endovascular aneurysm repair (EVAR) of abdominal aortic aneurysm (AAA) using LPE.

MATHERIALS AND METHODS

A literature search was conducted including articles that reported 30-days and follow-up mortality, complications, and reintervention rates of patients treated with EVAR using Incraft (Cordis), Zenith LP/Alpha (Cook Medical Inc) and Ovation (Endologix) endografts.

RESULTS

36 papers were evaluated, reporting results of 582 patients treated with Zenith device, 1211 with Incraft and 3449 with Ovation. During follow up, similar survival and freedom from reintervention rates were reported among the various types of endograft both at 1 and 3 years. The incidence of limb stenosis/kinking was significantly higher in patients treated with Zenith LP/Alpha (2.1%, P = 0.008), while the Incraft device had a significantly lower proportion of type III endoleaks (P < 0.001).

CONCLUSIONS

Long-term survival and freedom from reintervention rates were comparable among the three LPEs. The Cook Zenith device had the highest rates of limb stenosis/kinking, while the Incraft device had the lowest occurrence of type III endoleak.

PROSPERO

Registration number: CRD42022315875.

Outcomes of low- and standard-profile fenestrated and branched stent grafts for treatment of complex abdominal and thoracoabdominal aortic aneurysms

OBJECTIVE

We compared the outcomes of fenestrated-branched (FB) endovascular abdominal aortic aneurysm repair (EVAR) using low-profile (LP) and standard-profile (SP) stent grafts for the treatment of complex abdominal aortic aneurysms (CAAAs) and thoracoabdominal aortic aneurysms (TAAAs).

METHODS

We reviewed the clinical data of 466 consecutive patients (70% male; mean age, 74 ± 8 years) enrolled in a prospective nonrandomized study to investigate FB-EVAR for the treatment of CAAAs and TAAAs (2013-2021). The endpoints compared between the patients treated with LP (18F-20F) and SP (20F-22F) devices included procedural metrics, access-related complications, major adverse events (MAE), patient survival, freedom from secondary intervention, thromboembolic events, stent graft integrity issues, aneurysm sac enlargement, and the rate of sac shrinkage.

RESULTS

Of the 466 aneurysms treated by FB-EVAR, 138 were CAAAs and 141 were extent IV and 187 extent I to III TAAAs, with a mean number of 3.9 ± 0.5 vessels stented per patient. LP devices had been used in 239 patients (51%) and SP devices in 227 patients (49%). LP devices had been used more frequently for chronic dissections (12% vs 7%; P = .041) and with preloaded systems (77% vs 65%; P = .005) and bilateral percutaneous femoral access (83% vs 74%; P = .020) and less frequently with upper extremity access (67% vs 88%; P < .001) and iliac conduits (2% vs 6%; P = .020). The patients treated using LP devices had experienced similar technical success (96% vs 97%; P = .527), with a shorter total operating time (225 ± 81 minutes vs 243 ± 78 minutes; P = .018), lower radiation exposure (median, 0.93 Gy; interquartile range [IQR], 0.94; vs median, 1.01 Gy; IQR, 0.91 Gy; P < .001), and less use of contrast (median, 135 mL; IQR, 68 mL; vs median, 144 mL; IQR, 80 mL; P = .008). No differences were found in the rates of iliofemoral access complications between the LP and SP device groups (1.3% vs 3.5%; P = .107). At 30 days, 5 patients had died (1%) and MAEs had occurred in 89 patients (19%), with no differences between the two groups. The mean follow-up was 28 months (95% confidence interval, 25-30 months). At 4 years, the patients treated with LP devices had had similar freedom from all-cause mortality (69% ± 6% vs 68% ± 4%; P = .199), freedom from aortic-related mortality (97% ± 1% vs 98% ± 1%; P = .488), freedom from any secondary intervention (65% ± 6% vs 70% ± 4%; P = .433), freedom from thromboembolic events (98% ± 1% vs 99% ± 1%; P = .364) and aneurysm sac enlargement (93% ± 3% vs 91% ± 3%; P = .293). However, the LP group had had less freedom from any integrity-related issues (92% ± 5% vs 100%; P < .001). The cumulative risk of sac shrinkage was greater for patients treated with LP devices (adjusted hazard ratio, 2.040; 95% confidence interval, 1.516-2.744; P < .001).

CONCLUSIONS

FB-EVAR was performed with low rates of mortality and MAEs, irrespective of the device profile. However, the procedures performed with LP devices had had less need for iliac conduits and had had better procedural metrics. The use of LP devices resulted in higher rates of sac shrinkage. However, the results on stent graft integrity require future investigation.

Early Clinical Outcomes of Initial Launch of the Zenith Alpha Abdominal Endovascular Graft in Japan

Purpose:

This study retrospectively evaluated the 12-month outcomes of the Zenith Alpha Abdominal Endovascular graft (Zenith Alpha AAA, Cook, Inc, Bloomington, Indiana), which was launched partially in Japan in March 2019, starting with 9 selected sites.

Methods:

A retrospective analysis was performed of all endovascular aneurysm repairs (EVAR) for abdominal aortic aneurysms using the Zenith Alpha AAA. Late complications were defined as any aneurysm-related events occurring >30 days after EVAR, including an aneurysm sac enlargement of >5 mm and any reinterventions performed. Endoleaks without sac enlargement or reinterventions were excluded from late complications.

Results:

During the study period, 79 EVARs using the Zenith Alpha AAA were performed. The mean age was 76.6±6.9 years old, 91.1% of patients were male, and the mean aneurysm diameter was 51.1±7.5 mm. Instructions for use violation was observed in 27 patients (34.2%), most frequently being a severely angulated proximal neck (>60°). There were 4 intraoperative complications, including 2 unintentional partial renal artery coverages caused by the premature anchoring of the exposed suprarenal stent barb to the aortic wall, which was a result of the design change of the top cap deletion. Since it was a partial coverage without flow impairment and since renal stenting was unsuccessful, it was left untreated and had no subsequent renal function impairment. During the mean follow-up of 444±123 days, 74 patients completed 12 months of follow-up. Freedom from late complications at 12 months was 90.8%, which included 2 limb occlusions (2.5%). Of 71 patients with a 12-month computed tomography scan, there was only 1 type 1a endoleak (1.3%), 1 sac enlargement of >5 mm (1.3%), and an aneurysm sac shrinkage of >5 mm was observed in 42.2% of patients. There was no type 3 endoleak during the follow-up.

Conclusions:

This study demonstrated that the new generation of low-profile Zenith Alpha AAA has satisfactory early clinical outcomes, comparable to those obtained with the conventional Zenith endovascular graft. Long-term follow-up is needed to determine whether these favorable outcomes persist.

The Incraft stent graft for the treatment of abdominal aortic aneurysms: an iliac-friendly device with an effective conventional proximal sealing mechanism

INTRODUCTION

The Incraft aortic stent graft (Cordis, Bridgewater, NJ, USA) is a trimodular endovascular stent graft with a conventional suprarenal active fixation specifically designed to overcome the anatomic limitation of small, stenotic, and tortuous iliac vessels.

AREAS COVERED

The present article provides a complete description of the Incraft stent graft, its clinical performance, its technical characteristics as well as a comparison with other competitive endografts.

EXPERT OPINION

The Incraft stent graft is an EVAR ultra low-profile device initially designed for overcoming the limitation of the hostile iliac anatomy. Recently, the device is being increasingly used in real-world conditions and not only in complex iliac anatomies with good mid-term results. Whether it remains a useful EVAR toolbox or will become a workhorse endograft is yet to be determined.

Five-year results of the INSPIRATION study for the INCRAFT low-profile endovascular aortic stent graft system

OBJECTIVE

We present the 5-year results of a prospective regulatory study of the INCRAFT device, a low-profile endovascular stent graft system for repair of abdominal aortic aneurysms.

METHODS

This was an open-label prospective nonrandomized single-arm study enrolling in centers in the United States and Japan. The primary effectiveness outcome was successful aneurysm treatment and the primary safety outcome was the incidence of major adverse events at 30 days after the procedure. Major long-term outcomes were mortality, reintervention, adverse limb outcomes, and suprarenal stent fracture.

RESULTS

One hundred and ninety patients (mean age, 73.8 ± 7.6 years; 90% male; 69% white and 30% Asian) were enrolled from 32 centers throughout the United States and Japan. Minimal access vessel size was less than 7 mm on both sides in 43.9% of the study cohort. Thirty-day major adverse events occurred in 3.2% of patients (6/190). Periprocedural technical success was 94.1% (176/187). Successful aneurysm treatment was 100% at 30 days and 87.9% at 1 year. Two patients required open conversion for thromboembolic complications, 3 developed new type I or III endoleaks, and 7 experienced graft or limb occlusion. Freedom from graft occlusion was 96 ± 2% at 1 year and 94 ± 2% at 5 years. Freedom from stent fracture was 97 ± 1% at 1 year and 87 ± 3% at 5 years. Freedom from aneurysm-related mortality was 99 ± 1% at 1 and 5 years.

CONCLUSIONS

This study demonstrates good efficacy and safety and a very low rate of aneurysm related deaths with the INCRAFT device in a population with a high proportion of challenging anatomy.

Intraoperative Type IIIb Endoleak after Endograft Deployment during EVAR

Type IIIb endoleak usually occurs years after the initial endograft implantation, and the cause is the chronic fatigue of the endograft. This rare case describes a type IIIb endoleak, appearing immediately after deployment of a new generation low-profile stentgraft and highlights the diagnostic and treatment challenges associated with the type IIIb endoleak. A 74-year-old man underwent elective EVAR for an infrarenal abdominal aortic aneurysm. A type IIIb endoleak near to the flow divider due to a fabric defect was diagnosed. The endoleak was successfully treated by endovascular positioning of a converter stent graft followed by the occlusion of the left limb with an iliac occluder and a femoro-femoral crossover bypass surgery. The ultrasound scan after 4 weeks showed no sign of endoleak. Occurrence of a type IIIb endoleak immediately after deployment is extremely rare. Based on the convenience of the intraoperative procedure and the anatomic characteristics of the aneurysm, we assume that the fabric defect might have occurred during loading of the endograft and subsequent confinement in the delivery catheter. We cannot definitely rule out the possibility of fabric damage induced by low-pressure balloon instrumentation. In case of a suspicion of a type IIIb endoleak, bilateral balloon occlusion of both limbs followed by antergrade aortography will help to identify the leak. In case the defect is near to the flow divider, aortouniliac grafting followed by femoro-femoral crossover bypass surgery represents an alternative option to conversion to open surgical repair.

Infrarenal endovascular aneurysm repair: New developments and decision making in 2016

New developments in infrarenal abdominal aortic aneurysm stent-graft devices have made more patients eligible for endovascular aneurysm repair (EVAR). Recent US Food and Drug Administration approval for fenestrated endograft repair and impending approval for iliac branch devices extend the proximal and distal landing zones. Better deployment systems allow for partial deployment of endografts to facilitate repositioning, and more flexible designs allow for treatment of angulated infrarenal aneurysm necks and tortuous iliac arteries. New iterations of endografts have smaller delivery catheter diameters, which facilitate traversal of smaller access vessels. Long-term outcomes data are still accumulating and it remains to be seen whether EVAR for this expanded-indication abdominal aortic aneurysms anatomy has the same durability as standard EVAR. More options for repair also mean vascular surgeons must select the best EVAR device based on each patient's abdominal aortic aneurysm anatomy.