O072 A 10-year longitudinal cohort study assessing growth rates and surveillance intervals for common iliac artery aneurysms. (22nd July 2022) - Laloo, R
Abstract: Introduction: European Society for Vascular Surgery defines common iliac artery (CIA) aneurysms as greater than 1.8cm in men and 1.5cm in women. Reported growth rate is 1–4mm/year depending on their diameter. This study assessed the natural history and surveillance intervals for CIA aneurysms as intervention threshold is based on low-quality evidence. Methods: Patients with an IAA at a single vascular centre between 1st January 2010 and 31st August 2021 were identified from a prospectively collected departmental database and Caldicott-approved data collection performed. The primary outcomes included diameter-based mean aneurysm growth rates and median surveillance intervals. Statistical analysis with SPSS® was performed using chi squared tests. Results: Of 203 patients included, 90.6% were men and median (IQR) age at detection was 77(71–83). IAA were located in the CIA (85.2%), IIA (21.7%) and EIA (2.0%) with the majority being asymptomatic (78.8%). CT was most frequently used as the imaging modality for IAA surveillance (66.3%), followed by ultrasound scan (29.8%) and MRA (3.9%). Growth rate for CIA aneurysms measuring 1.0–1.9cm were -2.1mm/year, 2.0–2.9cm were 0.8mm/year, 3.0–3.9cm were 3.5mm/year, 4.0–4.9cm were 9.4mm/year, 5.0–5.9cm were 2.9mm/year and >6.0cm were 13.8mm/year. Median surveillance intervals for CIA aneurysms at 1.0–1.9cm were 12-monthly, 2.0–2.9cm were 11-monthly, 3.0–3.9cm were 5-monthly, 4.0–4.9cm were 5-monthly, 5.0–5.9cm were 5.5-monthly and >6.0cm were 14.5-monthly. Mean (SD) CIA diameter at rupture was 4.6 (2.4)cm. Conclusion: CIA aneurysms demonstrate faster growth rates as they enlarge and may require more frequent clinical assessments, surveillance and consideration for repair prior to rupture. Take-home message: CIA aneurysms demonstrate faster growth rates as they enlarge and may require more frequent clinical assessments, surveillance and consideration for repair prior to rupture.