The Aortic Leak

The argument in one sentence

A planned, elective AAA repair carries roughly a 1 to 4 percent operative mortality. A ruptured one kills about 80 percent of the patients it reaches, counting those who never make it to a hospital (Reimerink et al., British Journal of Surgery, 2013; elective figures from the Vascular Quality Initiative). The entire clinical and financial case for aortic care sits in the gap between those two numbers. Yet most programs lose patients on the way from one to the other, quietly, at three predictable points, and almost nobody is measuring the loss.

This is a report about those three leaks: where aortic patients fall out of care, what the evidence says it costs, and what it would take to close them.

The incidental aneurysm nobody acted on

Most AAAs are silent. They are found not because anyone went looking, but incidentally, on a CT ordered for back pain, kidney stones, or a cancer staging scan. In one recent series, 39 percent of patients who arrived with a ruptured AAA already had the aneurysm documented on a prior scan, found incidentally, before it ruptured (Wesche et al., Annals of Vascular Surgery, 2024; Norway). The aneurysm was visible. The system simply did not act on it.

The breakdown is one of communication, not clinical judgment. At a large multistate US radiology practice, before a reporting standard was put in place, only 2.1 percent of reports describing an incidental AAA included a recommendation for follow-up imaging. After the practice standardized its reporting, that figure rose to 58 percent (Journal of the American College of Radiology, 2021). The finding was on the image either way. What changed was whether anyone was told to do something about it. International audits describe an even leakier loop: incidental AAAs documented in the chart only about 29 percent of the time and communicated to the patient’s own physician only about 15 percent of the time (van Walraven et al., Journal of Vascular Surgery, 2010; Canadian data, included as corroboration).

This is also a liability surface. In an analysis of malpractice claims where an incidental finding contributed to harm, more than 41 percent resulted in an indemnity payment, and the recurring failure mode was simple: the responsible clinician was unaware of the finding, did not document it, or did not notify the patient (The Doctors Company, 2024). An incidental AAA that is seen but never communicated is both a clinical miss and a legal one.

The surveillance patient who quietly dropped out

A patient placed into surveillance is a patient the program has already found. Keeping them is the easy part, in theory. In practice, they leave.

Adherence to imaging surveillance after EVAR falls from 90 percent in the first year to 58 percent by year four (Newton et al., JAMA Network Open, 2025; 27,792 US veterans). In a national Medicare cohort, roughly half of patients had fallen out of guideline-concordant surveillance by five years (Schanzer et al., Journal of Vascular Surgery, 2014). Single-center prospective data are starker still: more than 40 percent of patients lost to follow-up entirely (Jasinski et al., Aorta, 2017). These are patients with a known aneurysm, in a known program, who simply stop coming back.

An honest report has to address the obvious question: does it matter? At least one large US claims study found that incomplete surveillance was not associated with worse outcomes (Garg et al., JAMA Surgery, 2015), most likely because administrative data cannot capture the patients who rupture and die outside a hospital. We take that finding seriously, and it points to the right conclusion. The problem is not that patients receive too little surveillance. It is that everyone receives the same surveillance. A 3.0 cm aneurysm and a 5.0 cm aneurysm are put on schedules that differ by a calendar, when the biology differs by years: the time for a 3.0 cm AAA to reach even a 10 percent chance of crossing the 5.5 cm threshold is about 7.4 years, versus 0.7 years at 5.0 cm (RESCAN collaborators, JAMA, 2013). The answer is not more surveillance. It is surveillance aimed at the patients who are actually moving.

The cost of the one-size schedule lands hardest on women. Women face a 3 to 4 times higher rupture risk than men at comparable diameters and rupture at smaller sizes (UK Small Aneurysm Trial; a clinical relationship that holds across populations). In US registry data, 17 percent of women ruptured below the standard 5.5 cm threshold, versus 10 percent of men (Lo, Schermerhorn et al., Journal of Vascular Surgery, 2013). A protocol built around a single diameter and a single interval is, for a meaningful fraction of women, built wrong.

The eligible patient nobody screened

The third leak is the one hiding in plain sight in the medical record. United States Preventive Services Task Force guidance recommends a one-time ultrasound for men aged 65 to 75 who have ever smoked (Grade B, current as of the 2019 statement). The Society for Vascular Surgery goes further, extending screening to women 65 to 75 with a tobacco history and to first-degree relatives of AAA patients.

By either standard, the patients are there and the screening is not. In one academic health system, of 6,682 patients who were eligible for AAA screening, only 6.9 percent actually received it (Annals of Vascular Surgery, 2021). These are not patients who need to be found in the community. They are already in the system, already have a chart, already came in for something else. They have simply never been flagged as eligible.

Women again absorb the gap. They are largely outside the USPSTF screening recommendation, yet their in-hospital mortality after ruptured AAA repair is 34.4 percent, against 26.6 percent for men (Society for Vascular Surgery / Vascular Quality Initiative). The population least likely to be screened is among the most likely to die when the aneurysm is missed.

What the leaks cost

The clinical cost is the gap from the opening sentence. Roughly 80 percent of ruptured AAAs are fatal, counting pre-hospital deaths, against 1 to 4 percent for an elective repair (EVAR 1.2 percent, open 3.8 percent). Even a ruptured aneurysm that reaches the operating room carries a 25 percent (endovascular) to 45 percent (open) operative mortality. A small aneurysm kept under genuine surveillance is remarkably safe, with a rupture rate near 0.3 percent, whereas a large aneurysm left unrepaired ruptures in about 26 percent of cases and kills roughly 22 percent from aortic causes (Leone et al., Journal of Clinical Medicine, 2023). The difference between catching a patient and losing one is, quite literally, the difference between a 1 percent problem and an 80 percent one.

The financial cost runs the same direction. An emergent rupture repair costs on the order of 3 to 4 times an elective one, with far longer intensive-care and hospital stays, and that is before accounting for the large share of rupture patients who never generate a bill because they do not survive. An elective repair, by contrast, is a scheduled, reimbursed, margin-positive procedure: one US center reported a hospital contribution margin near 8,000 dollars per elective EVAR (Brinster et al., Journal of Vascular Surgery, 2021). Every patient who leaks out is a patient who can return as the expensive, low-margin, high-mortality version of the same disease.

For a program, the math is uncomfortable: the patients leaking out today are tomorrow’s ruptures, and tomorrow’s ruptures are worse care and worse economics than the elective cases the program is built to deliver.

What it takes to close them

The three leaks share a structure, and so does the fix. None of it requires finding new patients. It requires not losing the ones already in the data.

1. 1.Find them where they already are. Incidental AAAs flagged in imaging, surveillance patients who have lapsed, screening-eligible patients sitting unidentified in the EHR: these are queries against records the program already owns, not new outreach.
2. 2.Personalize the interval. Replace the single calendar with a growth-aware schedule, so the patients who are actually moving, and the women who rupture small, get the attention the average patient does not need. This is the answer to the surveillance critique: better-targeted, not simply more.
3. 3.Make the inbound workable. Surfacing lost patients only helps if a real team can act on the list. Prediction has to triage the work so the program’s existing staff chase the patients who matter, not all of them at once.

This is the system we built Voythos’s AortaNavigator to be: a layer that finds the leaking patients, personalizes their surveillance against a growth model, and hands the program a worked, prioritized list rather than another dashboard.

About Voythos

Voythos builds software that helps vascular programs catch the aortic patients who currently fall through the cracks, with predictive models for aortic growth and risk underneath. Founded by Sophia Khan, MD, a vascular surgeon, and team.

References

1. Reimerink JJ et al. Systematic review and meta-analysis of population-based mortality from ruptured AAA. Br J Surg. 2013.
2. Wesche et al. 39% of ruptured AAA found incidentally pre-rupture. Ann Vasc Surg. 2024.
3. Standardizing incidental AAA reporting (2.1% to 58%). JACR. 2021.
4. van Walraven C et al. Incidence, follow-up, outcomes of incidental AAA. J Vasc Surg. 2010.
5. The Doctors Company. Detecting and addressing incidental findings. 2024.
6. Newton LE et al. Post-EVAR surveillance adherence (90% to 58%). JAMA Netw Open. 2025.
7. Schanzer A et al. Long-term post-EVAR surveillance. J Vasc Surg. 2014.
8. Jasinski PT et al. EVAR follow-up compliance. Aorta. 2017.
9. Garg T et al. Incomplete surveillance and outcomes (contrary evidence). JAMA Surg. 2015.
10. UK Small Aneurysm Trial. Sex and rupture risk. 1998 to 1999.
11. Lo RC, Schermerhorn ML et al. Sex, diameter, rupture. J Vasc Surg. 2013.
12. RESCAN collaborators. Growth and rupture of small AAA. JAMA. 2013.
13. USPSTF. AAA screening recommendation. 2019.
14. Society for Vascular Surgery. AAA practice guidelines (Chaikof et al.). J Vasc Surg. 2018.
15. Underutilization of AAA screening (6.9% of eligible). Ann Vasc Surg. 2021.
16. SVS/VQI. Women, mortality, and AAA repair (34.4% vs 26.6%).
17. Leone N et al. Rupture, repair, and death of AAA under surveillance. J Clin Med. 2023.
18. Brinster CJ et al. Financial viability of EVAR (~$8k margin per case). J Vasc Surg. 2021.