Management of Nellix migration and type Ia endoleak from proximal endovascular aneurysm sealing relining to late open conversion

First Case of Nellix Stent Rupture in a Huge Symptomatic Abdominal Aortic Aneurysm Who Underwent Endovascular Aneurysm Sealing 7 Years Before

PURPOSE

Despite encouraging early results, mid- and long-term follow-up of endovascular aneurysm sealing (EVAS) has shown increased rates of failure mainly associated with endoleak detection and progressive bag separation with aneurysm reperfusion.

CASE REPORT

We present the first case of a Nellix endograft stent fracture detected in a 91-year-old male patient, presenting with widespread abdominal pain, 7 years after elective treatment of an abdominal aortic aneurysm by EVAS. Considering the sudden and unexpected nature of the event, an in-depth analysis of the possible causes of this structural failure has been performed.

CONCLUSION

Material fatigue could be another significant cause of late EVAS failure and should be carefully assessed in addition to endoleak detection during follow-up.

CLINICAL IMPACT

The case presented in this article further underlines the importance of a strict long term follow-up protocol in every patients who underwent EVAS.

Combining Endovascular Aneurysm Sealing with Chimney Grafts - 5 Year Follow-Up after 47 Procedures

BACKGROUND

To evaluate longer-term results of a cohort treated with primary chimney endovascular aneurysm sealing (ChEVAS) for complex abdominal aortic aneurysms or secondary ChEVAS after failed endovascular aneurysm repair/endovascular aneurysm sealing.

METHODS

A single-center study was conducted of 47 consecutive patients (mean age 72 ± 8 years, range 50-91; 38 men) treated with ChEVAS from February 2014 to November 2016 and followed through December 2021. The main outcome measures were all-cause mortality (ACM), aneurysm-related mortality, occurrence of secondary complications and conversion to open surgery. Data are presented as the median (interquartile range [IQR]) and absolute range.

RESULTS

35 patients received a primary ChEVAS (=group I) and 12 patients a secondary ChEVAS (=group II). Technical success was 97% (group I) and 92% (group II); 30-day mortality was 3% and 8%, respectively. The median proximal sealing zone length was 20.5 mm (IQR 16, 24; range 10-48) in group I and 26 mm (IQR 17.5, 30; range 8-45) in group II, respectively. During a median time of follow-up of 62 months (range 0-88), ACM amounted to 60% (group I) and 58% (group II); aneurysm mortality was 29% and 8%, respectively. An endoleak was seen in 57% (group I: 15 type Ia endoleaks, four isolated type Ib, and 1 endoleak type V) and 25% (group II: 1 endoleak type Ia, one type II, and 2 type V), aneurysm growth in 40% and 17%, migration in 40% and 17%, resulting in 20% and 25% conversions in group I and II, respectively. Overall a secondary intervention was performed in 51% (group I) and 25% (group II), respectively. The occurrence of complications did not significantly differ between the 2 groups. Neither the number of chimney grafts, nor the thrombus ratio significantly affected the occurrence of abovementioned complications.

CONCLUSIONS

While initially delivering a high technical success rate, ChEVAS fails to provide acceptable longer-term results both in primary and secondary ChEVAS, resulting in high rates of complications, secondary interventions and open conversions.

Editor's Choice - Focused Update on Patients Treated with the Nellix EndoVascular Aneurysm Sealing (EVAS) System from the European Society for Vascular Surgery (ESVS) Abdominal Aortic Aneurysm Clinical Practice Guidelines

OBJECTIVE

After alerts on EndoVascular Aneurysm Seal (EVAS) failure were raised, the European Society for Vascular Surgery (ESVS) Abdominal Aortic Aneurysm (AAA) Clinical Practice Guidelines Writing Committee (WC) initiated a task force with the aim to provide guidance on surveillance and management of patients with implanted EVAS devices.

METHODS

Based on a scoping review of risk for late serious aortic-related adverse events in patients treated with EVAS for AAA, the ESVS AAA Guidelines WC agreed on recommendations graded according to the European Society of Cardiology (ESC) grading system.

RESULTS

EVAS has a very high incidence of late endograft migration resulting in proximal type 1 endoleak with risk of rupture, requiring open conversion with device explantation. The reported mortality rate for elective explantation varies between 0% and 14%, while acute conversion for rupture has a very dismal prognosis with a 67 - 75% mortality rate.

CONCLUSION

It is recommended that all patients in whom a Nellix device has been implanted should be identified, properly informed, and enrolled in enhanced surveillance. If device failure is detected, early elective device explantation should be considered in surgically fit patients.

A Case of Late Type Ia Endoleak After Endovascular Aneurysm Sealing Using the Nellix System: Proximal Extension with Triple Chimney and Gutter Endoleak Embolization

An 87-year-old man, who submitted to endovascular aneurysm sealing (EVAS) on 2017, presented a type Ia endoleak 2 years later, with enlargement of the aneurysmal sac. We planned an endovascular procedure of correction consisting of a proximal extension through two covered stent grafts deployed into the previous Nellix stent grafts, with associated triple chimney. However, 3 months later, he had a further 5 mm aneurysmal sac enlargement. He was submitted to angiography with coil embolization of gutters, obtaining a successfully result. At 1 and 3 months, he is free from endoleak, with a stable aneurysmal diameter.