A Review of UK-based National and International Scientific Meeting Published Abstracts in Response to the Draft NICE Aortic Aneurysm Guidelines

BACKGROUND

UK National Institute for Health and Care Excellence (NICE) draft clinical guidelines (CG) (2018) regarding aortic aneurysm repair were disputed internationally. We aim to appraise the academic response to the draft CG in terms of quantity and scientific quality by reviewing published conference abstracts from three major national and international, UK meetings.

METHODS

Abstracts related to aortic practice from The Vascular Societies Annual Scientific Meeting, British Society for Endovascular Therapy (BSET) & Charing Cross (CX) meetings from 2019 were reviewed for methodology, sample size, data collection period, scientific quality and conclusions that supported or conflicted the draft guideline.

RESULTS

A total of 549 abstracts were identified from VSGBI, BSET and CX abstract books of which, 226 (41.2%) were related to aortic practices. Of these, 115 (50.9%) were related to EVAR. Twenty-two of these abstracts (19.1%) were identified as having findings relevant to the draft guidelines. Eighteen (15.7%) were identified as findings that potentially conflict the draft CG and 4 (3.5%) that could support the initial recommendations. Six abstracts (5.2%) made direct reference to or challenged the draft CG. The median data collection period was 4 years. The median sample size was 102 patients. In general, scientific quality was poor, with 82% of selected abstracts were graded at level 2b.

CONCLUSION

We have demonstrated a concerted response to the draft NICE clinical guidelines relating to the treatment of abdominal aortic aneurysms at three large scientific meetings. As a result of which and other factors, significant changes were made to the finalized NG156. There is still paucity in evidence regarding the long-term safety and cost-effectiveness of EVAR.

Long-term chimney/snorkel endovascular aortic aneurysm repair experience for complex abdominal aortic pathologies within the PERICLES registry

OBJECTIVE

The early and short-term efficacy of the snorkel/chimney technique for endovascular aortic aneurysm repair (ch-EVAR) have been previously reported. However, long-term ch-EVAR performance, vessel patency, and patient survival remain unknown. Our study evaluated the late outcomes to identify possible predictors of failure within the PERICLES (performance of the chimney technique for the treatment of complex aortic pathologies) registry.

METHODS

Clinical and radiographic data from patients who had undergone ch-EVAR from 2008 to 2014 in the PERICLES registry were updated with an extension of the follow-up. Regression models were used to evaluate the relevant anatomic and operative characteristics as factors influencing the late results. We focused on patients with ≥30 months of follow-up (mean, 46.6 months; range, 30-120 months).

RESULTS

A total of 517 patients from the initial PERICLES registry were included in the present analysis, from which the mean follow-up was updated from 17.1 months to 28.2 months (range, 1-120 months). All-cause mortality at the latest follow-up was 25.5% (n = 132), with an estimated patient survival of 87.6%, 74.4%, and 66.1% at 1, 3, and 5 years, respectively. A subgroup of 244 patients with 387 chimney grafts placed (335 renal arteries, 42 superior mesenteric arteries, 10 celiac arteries) and follow-up for ≥30 months was used to analyze specific anatomic and device predictors of adverse events. In the subgroup, the technical success was 88.9%, and the primary patency was 94%, 92.8%, 92%, and 90.5% at 2.5, 3, 4, and 5 years, respectively. The mean aneurysm sac regression was 7.8 ± 11.4 mm (P < .0001). Chimney graft occlusion had occurred in 24 target vessels (6.2%). Late open conversion was required in 5 patients for endograft infection in 2, persistent type Ia endoleak in 2, and endotension in 1 patient. The absence of an infrarenal neck (odds ratio, 2.86; 95% confidence interval, 1.32-6.19; P = .007) was significantly associated with long-term device-related complications. A sealing zone diameter >30 mm was significantly associated with persistent or late type Ia endoleak (odds ratio, 4.86; 95% confidence interval, 1.42-16.59; P = .012).

CONCLUSIONS

The present analysis of the PERICLES registry has provided the missing long-term experience for the ch-EVAR technique, showing favorable results with more than one half of the patients surviving for >5 years and a chimney graft branch vessel patency of 92%. The absence of an infrarenal neck and treatment with a sealing zone diameter >30 mm were the main anatomic long-term limits of the technique, requiring adequate preoperative planning and determination of the appropriate indication.