Interventional procedure overview of endoanchoring systems in endovascular aortic aneurysm repair

Mortality

All-cause 30-day mortality was 1% (95% CI 0.2% to 2%) in the EVAR cohort of patients (n=562) in the systematic review of 628 patients. For patients who had TEVAR (n=66), weighted all-cause 30-day mortality was 12% (95% CI 5% to 21%; Qamhawi, 2020).

There was no aneurysm-related mortality and mortality not related to the procedure was 5% (6/116) in 116 patients with hostile neck characteristics included in the systematic review of 968 patients (Karaolanis, 2020).

Mortality was 3% (9/319) in the cohort of 319 patients, none of which was aneurysm or device related (Jordan, 2014).

Aneurysm-related mortality within 30 days was 2% (4/221) in a cohort study of 221 patients; 1 patient died from multiorgan failure, 2 died from sepsis and pneumonia and 1 died from an endograft infection. Non-aneurysm related mortality during follow up was 10% (21/221).

There was 1 death within 30 days in the single-arm study of 155 patients. The patient died 18 days after the index procedure that was complicated by rupture of an iliac artery during balloon angioplasty of a graft limb. There was 1 additional aneurysm-related death after 3 years caused by haemorrhagic stroke. This was adjudicated to be related to warfarin prescribed to treat a pulmonary embolism after an abdominal aortic aneurysm-related reintervention (Mehta, 2014).

There were 27 deaths reported during the index hospitalisation or during follow up on the FDA MAUDE database. Of these, 15 were of unknown aetiology or considered to be unrelated to the index procedure, and 12 reports were thought to be related to the index EVAR procedure rather than endoanchor use. In 1 report, multiple tiny holes were seen at the site of endoanchor insertion in fabric at the time of explant. The reporting physician thought these contributed to worsening endoleak (Masoomi, 2019).

Aneurysm rupture

No aneurysm rupture was reported in the systematic review of 968 patients with mean follow up of 10 months (Karaolanis, 2020).

Endoanchor fracture, dislocation, or entrapment

Endoanchor fracture and dislocation were each reported in 3 patients who had EVAR in the systematic review of 628 patients. An entrapped endoanchor needing snare retrieval was reported in 1 patient in the same review. A maldeployed endoanchor was reported in 2 patients who had TEVAR. In 1 of these patients, the endoanchor was irretrievable, resulting in a retrograde type A aortic dissection and death (Qamhawi, 2020).

Endoanchor fractures were reported in 2% (4/221) of patients (no treatment was necessary) in the cohort study of 221 patients. Endoanchor losses were reported in 2% (4/221) of patients, 2 were snared, 1 was caged and 1 was left in the main endograft body. There were also 2 reports of a twisted device in the same study, which were treated by changing the catheter. None of these issues caused any type of intraoperative or follow-up complication or failure (Valdivia, 2021).

Endoanchor dislodgement or fracture was described in 65 reports in the FDA MAUDE database (1% of estimated total device systems used). Guide or applier malfunction was described in 20 reports (Masoomi, 2019).

Myocardial infarction

Myocardial infarction was reported in 1% (2/155) of patients within 30 days, 5% (7/155) within 1 year and 7% (10/155) within 3 years of the index procedure in the single-arm study of 155 patients (Mehta, 2014).

Stroke

Stroke was reported in 2% (3/155) of patients within 1 year and 5% (7/155) within 3 years of the index procedure in the single-arm study of 155 patients (Mehta, 2014).

Renal failure

Renal failure was reported in 1% (2/155) of patients within 1 year and 4% (6/155) within 3 years of the index procedure in the single-arm study of 155 patients (Mehta, 2014).

Thrombus-related events

Device-related thrombotic events were reported in 21% (32/155) of patients (49 events) within 1 year of implantation and 36% (56/155) of patients (104 events) within 3 years. Limb occlusion was 5% (7/155) at 1 year and 8% (12/155) at 3 years. Distal embolic events linked to the endograft were reported in 10% (15/155) of patients at 1 year and 15% (23/155) at 3 years. Nonocclusive thrombus identified by imaging was reported in 10% (15/155) at 1 year and 21% (33/155) at 3 years. The authors noted that the endograft device was subsequently modified to reduce the rate of thrombus-related events (Mehta, 2014).

Air embolism

Air embolism associated with the use of endoanchors in EVAR was described in 5 reports on the FDA MAUDE database (0.07% of estimated total device systems used). No long-term clinical consequences were reported (Masoomi, 2019).

Respiratory failure

Respiratory failure was reported in 1% (1/155) within 1 year and 2% (3/155) within 3 years of the index procedure in the single-arm study of 155 patients (Mehta, 2014).

Anecdotal and theoretical adverse events

In addition to safety outcomes reported in the literature, professional experts are asked about anecdotal adverse events (events which they have heard about) and about theoretical adverse events (events which they think might possibly occur, even if they have never happened).

For this procedure, professional experts did not describe any anecdotal adverse events. They considered that the following were theoretical adverse events: endoanchoring close to the renal arteries can cause on table hypotension in the patient, the potential for an endoanchor to be detached from the delivery system and embolise distally, vascular access complications, the delivery of the anchors can be time consuming with the X-ray gantry at high angles which increases the X-ray dose to the patients and operators and there is a potential for skin damage in doses greater than 1 gray.