Abdominal aortic aneurysm calcification: trying to identify a reliable semiquantitative method

BACKGROUND: The main objective of this study was to assess the correlation between three semiquantitative and one computerized method based on Agatston Score (AS), when measuring abdominal aortic calcification (AAC) in abdominal aortic aneurysm (AAA) patients. Secondary aim was to access differences in AAC upon clinical variables, when different methods of calcium scoring are used. METHODS: This was an observational, retrospective, cross-sectional study. A database of AAA patients consecutively submitted to elective repair between 2008 and 2015 was used. Patients were excluded if they did not have preoperative imaging or presented scans incompatible with at least one of the whole set of calcification methods tested. Calcification measures were performed using AS, Aortic Calcification Index (ACI), AAC-8 and AAC-24 methods. The Pearson's correlation was used for primary analysis. RESULTS: Study population comprised 102 patients, 95% males, with a median age of 71 (interquartile range, IQR 66-76) years. AAAs presented median aortic diameter of 60 (54-70) mm. Pearson's correlation with AS was 0.816 for ACI, 0.703 for AAC-8 and 0.648 for AAC-24. ACI also presented the highest ICC for intraobserver agreement (0.972) and for interobserver agreement (0.966). ACI was associated more often to demographic and clinical variables in the dataset that associated with the computerized method. CONCLUSIONS: ACI is suggested as a fast and easy-to-use method of assessing AAC in AAA patients. Its use should be encouraged to study AAC in AAA over other semiquantitative methods, in research settings.