The anatomy characteristics of 7000 inferior abdominal aortic aneurysms, CHAP patient cohort (percentiles) by gender

CHAP, the Characterization of Human Aortic Anatomy Project, which started in 2009 by the Food
and Drug Administration (FDA) and practicing clinicians in the community, is a
collaboration to gather and analyze anatomic data from patients with aortic
aneurysms.  One of CHAP’s first goals is
to characterize the anatomy of unrepaired infrarenal AAA (iAAA) from a large
subset of the patient population, with the hope of elucidating pertinent
anatomical differences between men and women that might lead to treatment
disparities, and to expand patient eligibility for EVAR by identifying criteria
for augmenting endovascular design and evaluation.  The CHAP database contains data from centers
that consecutively submit[1]
their pre-operative CT scans of unrepaired aneurysm cases to M2S for analysis
and surgical planning.  M2S, Inc.
(Lebanon, NH) is a third party core lab that independently reviews each scan
and records anatomic measurements that define the geometry and shape of
aneurysms and other vascular pathologies. 

The
following studies have been conducted under CHAP with approval from the FDA and
center specific Institutional Review Boards: (i) Single center anatomical study
[1], (ii) 3-center anatomical study [2], (iii) 11-center anatomical study,
current study.  For these studies, the
measurements (as listed in the Table below) of the iAAA anatomy were determined
in conjunction with SVS reporting standards [3]. The table below are the data
from the CHAP database for infrarenal AAA binned by gender.

[1]
Sweet MP, Fillinger MF, Morrison TM, and Abel DB. J Vasc Surg 2011;54(4):931-7.

[2]
Morrison, T.M., Yan, X., Abel, D.B., Fairman, R.M., Glickman, M.H., and
Fillinger, M.F.,  J of Vasc Surg,
55(6):30S 2012

[3]
Chaikof EL, Blankensteijn JD, Harris PL, et al. J Vasc Surg 2002;35:1048-60.

[1] Two sites
consecutively submitted cases that were considered for EVAR only.  We tested for heterogeneity and there were no
statistical differences between those sites and the 9 remaining center.  Therefore, we determined that it was
acceptable to keep data from all 11 centers.