{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"medRxiv"}],"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T14:07:28Z","timestamp":1790086048572,"version":"4.0.1"},"posted":{"date-parts":[[2025,10,1]]},"group-title":"Surgery","reference-count":45,"publisher":"openRxiv","license":[{"start":{"date-parts":[[2025,10,1]],"date-time":"2025-10-01T00:00:00Z","timestamp":1759276800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"award":["R01-HL159205"],"award-info":[{"award-number":["R01-HL159205"]}],"id":[{"id":"https:\/\/ror.org\/01cwqze88","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2026,9,18]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                <jats:p>Biological tissue reorganizes in response to changes in its mechanical environment, yet quantitative models of that reorganization are almost always built where observations are dense. At organ-scale in living humans the observational data is sparse and noisy: a few irregularly spaced images per individual, acquired with variable instrumentation, with loss to follow-up and patient attrition. We ask whether governing equations for organ-scale remodeling can be recovered from this regime, and pose what those equations may reveal about the underlying biology.<\/jats:p>\n                <jats:p>\n                  We study the human abdominal aorta following endovascular aneurysm repair (EVAR), in which a stent graft excludes the aneurysm sac from arterial flow and thereby changes the mechanical loading of the sac wall. Each computed tomography (CT) scan is reduced to a two-dimensional state: surface area\n                  <jats:italic>\u00c3<\/jats:italic>\n                  (size) and fluctuation in integrated Gaussian curvature\n                  <jats:inline-formula>\n                    <jats:inline-graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" xlink:href=\"25336910v3_inline1.gif\"\/>\n                  <\/jats:inline-formula>\n                  (shape), both normalized to a non-pathological aortic population. Across 100 patients and 220 scans pooled from two international centers, we use Z\u2013SINDy, a sparse identification method with statistical-mechanical uncertainty quantification, to infer affine systems of ordinary differential equations (ODEs) governing\n                  <jats:inline-formula>\n                    <jats:inline-graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" xlink:href=\"25336910v3_inline2.gif\"\/>\n                  <\/jats:inline-formula>\n                  for anatomy that remodels successfully (regressing sacs) and anatomy that does not (stable sacs).\n                <\/jats:p>\n                <jats:p>\n                  Both outcome classes approach stable fixed points, but at different locations in the morphological state space and on different timescales. Regressing anatomy approaches\n                  <jats:inline-formula>\n                    <jats:inline-graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" xlink:href=\"25336910v3_inline3.gif\"\/>\n                  <\/jats:inline-formula>\n                  = (2.0,1.0) with characteristic timescales of 1.3 and 4.6 years; stable anatomy approaches its fixed point of (3.8, 2.5) with an order of magnitude slower timescale (10.9 and 16.6 years). Embedding the learned equations within Bayesian classifiers demonstrates that trajectory-based information resolves patient outcome classification earlier than positional evidence alone. Toward model utilization in future studies, these advantages are also observed when empirically observed loss to follow-up is carried through the priors. Recovering the equations that govern remodeling, rather than tracking its instantaneous state, therefore provides a foundation for clinical models built from the sparse records that routine imaging surveillance actually produces.\n                <\/jats:p>","DOI":"10.1101\/2025.09.29.25336910","type":"posted-content","created":{"date-parts":[[2025,10,1]],"date-time":"2025-10-01T21:40:12Z","timestamp":1759354812000},"source":"Crossref","is-referenced-by-count":1,"title":["Learned Human Aortic Morphodynamics: A Dynamical-Systems Model of Post-EVAR Sac Remodeling"],"prefix":"10.64898","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3295-5664","authenticated-orcid":false,"given":"Joseph A.","family":"Pugar","sequence":"first","affiliation":[{"name":"Department of Surgery, University of Chicago, 5841 S Maryland Avenue, Chicago, IL 60637, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Junsung","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Surgery, University of Chicago, 5841 S Maryland Avenue, Chicago, IL 60637, USA"},{"name":"Harvard Medical School, Harvard University, 25 Shattuck Street, Boston, MA 02115, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-5225-8500","authenticated-orcid":false,"given":"Michael","family":"Mansour","sequence":"additional","affiliation":[{"name":"Department of Surgery, University of Chicago, 5841 S Maryland Avenue, Chicago, IL 60637, USA"},{"name":"Department of Medical Physics, University of Chicago, 5720 S Ellis Avenue, Chicago, IL 60637, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Charles","family":"Davis","sequence":"additional","affiliation":[{"name":"Department of Surgery, University of Chicago, 5841 S Maryland Avenue, Chicago, IL 60637, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nhung","family":"Nguyen","sequence":"additional","affiliation":[{"name":"Department of Surgery, University of Chicago, 5841 S Maryland Avenue, Chicago, IL 60637, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cheong Jun","family":"Lee","sequence":"additional","affiliation":[{"name":"Endeavor Health, 2650 Ridge Avenue, Evanston, IL 60201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Trissa","family":"Babrowski","sequence":"additional","affiliation":[{"name":"Department of Surgery, University of Chicago, 5841 S Maryland Avenue, Chicago, IL 60637, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hence","family":"Verhagen","sequence":"additional","affiliation":[{"name":"Department of Vascular Surgery, Erasmus University Medical Center, Doctor Molewaterplein 40, 3015 GD Rotterdam, the Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ross","family":"Milner","sequence":"additional","affiliation":[{"name":"Department of Surgery, University of Chicago, 5841 S Maryland Avenue, Chicago, IL 60637, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5740-8520","authenticated-orcid":false,"given":"Andrei A.","family":"Klishin","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, University of Hawai\u2018i at M\u0101noa, 2540 Dole Street, Honolulu, HI 96822, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2652-9714","authenticated-orcid":false,"given":"Luka","family":"Pocivavsek","sequence":"additional","affiliation":[{"name":"Department of Surgery, University of Chicago, 5841 S Maryland Avenue, Chicago, IL 60637, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"54368","reference":[{"key":"2026092206500801000_2025.09.29.25336910v3.1","doi-asserted-by":"publisher","DOI":"10.1016\/j.cell.2023.11.041"},{"key":"2026092206500801000_2025.09.29.25336910v3.2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.2206994120"},{"key":"2026092206500801000_2025.09.29.25336910v3.3","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.1517384113"},{"key":"2026092206500801000_2025.09.29.25336910v3.4","doi-asserted-by":"publisher","DOI":"10.1126\/sciadv.1602614"},{"key":"2026092206500801000_2025.09.29.25336910v3.5","unstructured":"Ming Han , John Devany , Michel Fruchart , Margaret L. 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