624 A Retrospective Review of Blood Pressure Variability (BPV) and Abdominal Aortic Aneurysm (AAA)

Abstract

Abstract Background Abdominal aortic aneurysms (AAA) rupture risk increases with expansion. Understanding of factors influencing AAA growth are crucial to reduce the risk of rupture. Blood pressure (BP) is considered a contributor to AAA formation, but the association with AAA growth remains unclear. Blood pressure variability (BPV) has emerged as an important cardiovascular risk factor, yet its relationship with AAA growth has not been investigated. Method A retrospective review of 90 patients participating in a multi-centre AAA growth study (NCT05376514) was conducted. Mean growth (mm/yr) was calculated from first and most recent duplex ultrasound scans. Outpatient BP readings between scans were used to calculate BPV defined as the standard deviation (SD) of systolic and diastolic values. Patients were stratified into high and low BPV groups and again into tertiles. Mann-whitney U and unpaired T-tests were used for group comparisons, Kruskall-Wallis to assess for a dose-response relationship between tertiles of BPV. Multiple regression analysis examined variable impact on growth. Results High diastolic BPV was associated with a faster growth rate (2.05 mm/yr [IQR= 1.00 – 3.00]) vs low diastolic BPV (1.44 mm/ yr ([IQR= 0.475-2.00]p=0.036) with a significant dose-response relationship between the lowest and highest BPV tertiles (p= 0.019). DBPV was a significant predictor of AAA growth in the multiple regression model for tertile classification (p=0.016). There was no association between systolic BPV and faster AAA growth rates. Conclusions There was a significant association between higher diastolic blood pressure variability and AAA growth. DBPV may be an important risk stratification tool.