Aortic Aneurysm

An aortic aneurysm is a permanent, localised dilatation of the aorta to at least 1.5 times its expected diameter. It matters to physiotherapy for one reason above all others: the aneurysm itself is silent, but the activities we prescribe raise arterial pressure, and the decision about how hard a patient may work is made against a size threshold most clinicians never see written down.^1,2

Definition and classification

Aneurysms are described by location. Abdominal aortic aneurysm (AAA) is the most common, defined as an infrarenal aortic diameter of ≥30 mm. Thoracic aortic aneurysm (TAA) affects the ascending aorta, arch or descending thoracic aorta, and is more often associated with connective tissue disease. Thoracoabdominal aneurysms span both. A distinction worth holding: a true aneurysm involves all three vessel wall layers, whereas a pseudoaneurysm is a contained rupture — the latter is unstable and is not an exercise question.^1,3

Pathophysiology

Degenerative AAA involves elastin fragmentation, smooth muscle apoptosis and inflammatory infiltration of the media, with matrix metalloproteinase activity exceeding its inhibition. Wall stress rises with diameter in accordance with Laplace's law, which is why rupture risk accelerates rather than climbs linearly. Thoracic aneurysms more often reflect an underlying medial abnormality — Marfan syndrome, Loeys–Dietz, vascular Ehlers–Danlos, or bicuspid aortic valve associated aortopathy — and behave differently, rupturing or dissecting at smaller diameters.^1,4

Co-morbidities

Aortic aneurysm is rarely an isolated diagnosis. Coronary artery disease coexists in a large proportion and is the leading cause of death in people with a small aneurysm, which is why the cardiovascular assessment matters more than the aneurysm itself in day-to-day management.⁸ Chronic obstructive pulmonary disease shares smoking as a cause and is present often enough that pre-operative respiratory assessment is routine. Peripheral arterial disease, cerebrovascular disease, hypertension and chronic kidney disease cluster with it. Aneurysms elsewhere — popliteal, femoral, iliac and thoracic — are more common in this group, so one aneurysm is a reason to consider others.

Prevalence and risk factors

AAA affects roughly 1–2% of men over 65 and considerably fewer women, though women rupture at smaller diameters and have worse outcomes. Smoking is the dominant modifiable risk factor, with a dose–response relationship and a stronger association than for almost any other cardiovascular condition. Age, male sex, family history, hypertension and existing atherosclerotic disease all contribute. Diabetes is, unusually, associated with reduced AAA risk.^2,5

Presentation

The great majority are asymptomatic and detected incidentally on imaging performed for another reason, or through screening. Symptomatic presentations — new back, flank or abdominal pain, or a pulsatile abdominal mass — suggest rapid expansion or impending rupture and are a medical emergency. Thoracic aneurysms may cause hoarseness, dysphagia or, rarely, breathlessness through compression, which is why a cardiorespiratory service occasionally meets one first.

Diagnosis and surveillance

Ultrasound is the screening and surveillance tool of choice for AAA; CT angiography defines anatomy before intervention. Surveillance intervals shorten as diameter increases, and elective repair is generally considered at ≥55 mm in men and ≥50 mm in women, or with growth exceeding about 10 mm per year, though thresholds differ between guidelines and are lower in connective tissue disease.^1,3

Medical and surgical management

Below the threshold, management is risk-factor modification and surveillance: smoking cessation above all, blood pressure control, and statin and antiplatelet therapy for global cardiovascular risk. Repair is by open surgery or endovascular aneurysm repair (EVAR); EVAR has lower perioperative mortality but requires lifelong imaging surveillance for endoleak.³

Medications

No drug reliably slows aneurysm growth, which is a genuine disappointment of the field — beta-blockers, doxycycline and ACE inhibitors have all been trialled without convincing effect on expansion.³ Treatment is therefore directed at global cardiovascular risk: statins and antiplatelet therapy, and blood-pressure control with whatever agent suits the patient. ⚠ For us, the practical consequence is that most patients are beta-blocked or on other rate-limiting agents, so heart-rate targets are unreliable and prescription runs on workload and perceived exertion — see prescribing exercise from test results.

Multi-system manifestations

Where the aneurysm is part of a connective tissue disorder, it is one feature of a systemic condition. Marfan syndrome brings ocular, skeletal and dural involvement; vascular Ehlers–Danlos affects skin, joints and hollow organs with a bleeding tendency; Loeys–Dietz adds craniofacial and skeletal features.⁴ These change handling as well as intensity, and joint hypermobility alters what resistance work is appropriate. Degenerative aneurysm carries its own systemic burden through shared atherosclerotic disease, and inflammatory aortitis occasionally underlies it.

Living with an aortic aneurysm

Most people find out incidentally and feel entirely well, which makes the diagnosis peculiarly difficult: nothing has changed in how they feel, yet they have been told they have a condition that might rupture. Anxiety is common and under-addressed, and some patients restrict activity far beyond anything advised — occasionally giving up work or exercise altogether on a misunderstanding. Explaining that supervised exercise is encouraged, and that the restrictions concern straining rather than exertion, is one of the more valuable conversations available. Practical points worth covering: what to do about constipation and heavy lifting at work, that surveillance scans are reassurance rather than threat, and when to seek urgent help.

Prognosis

For a small aneurysm under surveillance, prognosis is dominated by cardiovascular risk rather than rupture — most of these patients die of coronary disease.⁸ Rupture risk rises steeply with diameter, which is what the size thresholds encode; below 40 mm annual rupture risk is very low, and elective repair is offered when it exceeds the operative risk. Smoking cessation is the single most powerful modifier of both growth and mortality.² Elective repair has good outcomes; emergency repair after rupture does not, which is the entire argument for surveillance.

Exercise and the aneurysm — the part that concerns us most

Supervised exercise is safe and is recommended, and the historical instinct to deconditioning patients with an aneurysm was wrong. Trials of supervised exercise in people with small-to-moderate AAA have shown improved cardiorespiratory fitness without accelerating aneurysm growth, and pre-operative exercise training reduces cardiac and respiratory complications after repair.^6,7,8 Given that most deaths in this population are cardiac rather than from rupture, improving fitness addresses the more likely cause of harm.

What is limited is the pressure response, not exercise itself:

• Aerobic training is the mainstay. Moderate-intensity continuous work, and supervised interval work in trial settings, have been delivered without adverse aneurysm outcomes.
• Avoid maximal isometric effort and the Valsalva manoeuvre. Heavy straining produces brief, very large rises in systolic pressure. Teach exhalation on exertion and prescribe resistance work at moderate loads with higher repetitions rather than near-maximal lifts.
• Blood pressure is the variable to watch, more than heart rate. Uncontrolled resting hypertension should be addressed before progressing intensity.
• Competitive and collision sport is generally advised against in larger aneurysms and in connective tissue aortopathy, where guidance is considerably more conservative.^4,9

Airway clearance and the abdominal thrust

A known AAA is a contraindication to manually assisted cough using an abdominal thrust, and appears as such in our assisted cough guidance. Alternative techniques — anterior chest compression, mechanical insufflation–exsufflation, breath stacking — remain available. This is the one place an aneurysm reaches routine respiratory practice, and it is easily missed because the aneurysm is rarely the reason for referral.

Role of the physiotherapist

Deliver supervised aerobic and moderate-load resistance training within the limits above; teach breathing technique that avoids Valsalva; support smoking cessation as the single highest-value intervention available (see smoking cessation); prepare patients for elective repair with prehabilitation; and rehabilitate afterwards, where the presentation is a major abdominal or thoracic surgical recovery. Escalate immediately for new or changed back, flank or abdominal pain.

Warning signs

Part 1 · References

1. Isselbacher EM, Preventza O, Hamilton Black J, et al. 2022 ACC/AHA guideline for the diagnosis and management of aortic disease. Circulation 2022;146(24):e334–e482.
2. Sakalihasan N, Michel JB, Katsargyris A, et al. Abdominal aortic aneurysms. Nat Rev Dis Primers 2018;4(1):34.
3. Wanhainen A, Van Herzeele I, Bastos Goncalves F, et al. European Society for Vascular Surgery 2024 clinical practice guidelines on the management of abdominal aorto-iliac artery aneurysms. Eur J Vasc Endovasc Surg 2024;67(2):192–331.
4. Pelliccia A, Sharma S, Gati S, et al. 2020 ESC guidelines on sports cardiology and exercise in patients with cardiovascular disease. Eur Heart J 2021;42(1):17–96.
5. Kent KC. Clinical practice. Abdominal aortic aneurysms. N Engl J Med 2014;371(22):2101–2108.
6. Tew GA, Batterham AM, Colling K, et al. Randomized feasibility trial of high-intensity interval training before elective abdominal aortic aneurysm repair. Br J Surg 2017;104(13):1791–1801.
7. Myers JN, White JJ, Narasimhan B, Dalman RL. Effects of exercise training in patients with abdominal aortic aneurysm: preliminary results from a randomized trial. J Cardiopulm Rehabil Prev 2010;30(6):374–383.
8. Fenton C, Tan AR, Abaraogu UO, McCaslin JE. Exercise training for management of people with abdominal aortic aneurysm. Cochrane Database Syst Rev 2020;7:CD013529.
9. Braverman AC, Harris KM, Kovacs RJ, Maron BJ. Eligibility and disqualification recommendations for competitive athletes with cardiovascular abnormalities: task force 7 — aortic diseases. Circulation 2015;132(22):e303–e309.

References are numbered in citation order (Vancouver/BMJ style) and were current at the time of writing. Guidelines are living documents — verify against the latest version before clinical use.