Treatment algorithm

Please note that formulations/routes and doses may differ between drug names and brands, drug formularies, or locations. Treatment recommendations are specific to patient groups: see disclaimer

ACUTE

ruptured AAA

1st line – standard resuscitation measures

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ACUTE
|
ruptured AAA
1st line – 

standard resuscitation measures

Standard resuscitation measures should be initiated immediately. These include: airway management (supplemental oxygen or endotracheal intubation and assisted ventilation if the patient is unconscious); securing intravenous access (central venous catheter); arterial catheter and urinary catheter; ensuring blood product availability (packed red cells, platelets, and fresh frozen plasma) and transfusing for resuscitation, severe anemia, and coagulopathy; and notifying anesthetic, intensive care unit (ICU), and operating teams.

Aggressive fluid replacement may cause dilutional and hypothermic coagulopathy and secondary clot disruption from increased blood flow, increased perfusion pressure, and decreased blood viscosity, thereby exacerbating bleeding.​[119]​​[120]​ A target systolic blood pressure (SBP) of 50 to 70 mmHg and withholding fluids is advocated preoperatively.[119]​​[120]​​ The American College of Cardiology/American Heart Association (ACC/AHA) guidelines recommend permissive hypotension to reduce bleeding.[5]​ However, recommended targets vary and there is no consensus among global guideline groups. 

Tracheal intubation: animated demonstration
Tracheal intubation: animated demonstration

How to insert a tracheal tube in an adult using a laryngoscope.

Bag-valve-mask ventilation: animated demonstration
Bag-valve-mask ventilation: animated demonstration

How to use bag-valve-mask apparatus to deliver ventilatory support to adults. Video demonstrates the two-person technique.

Plus – urgent surgical repair

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ACUTE
|
ruptured AAA
Plus – 

urgent surgical repair

Treatment recommended for ALL patients in selected patient group

The American College of Cardiology/American Heart Association (ACC/AHA) recommend computed tomography (CT) imaging in patients presenting with ruptured AAA who are hemodynamically stable to evaluate whether the AAA is amenable to endovascular repair.[5]​ This recommendation is supported by results from the IMPROVE multicenter randomized controlled trial, which suggest that for most patients, confirmatory CT did not add significant delays to treatment and facilitated appropriate preoperative planning.[108]

If the anatomy is suitable, the ACC/AHA recommend endovascular repair over open repair to reduce the risk of morbidity and mortality.[5] ​In patients with confirmed ruptured AAA, 3-year mortality was lower among those randomized to endovascular aneurysm repair (EVAR) than to an open repair strategy (48% vs. 56%; hazard ratio [HR] 0.57, 95% CI 0.36 to 0.90).[109] The difference between treatment groups was no longer evident after 7 years of follow-up (HR 0.92, 95% CI 0.75 to 1.13). Re-intervention rates were not significantly different between the randomized groups at 3 years (HR 1.02, 95% CI 0.79 to 1.32).[109]​ There is some evidence to suggest that an endovascular strategy for repair of ruptured AAA may reduce mortality more effectively in women than in men.[109][110]​​​

There is some evidence to suggest that mode of anesthesia for operative repair of AAA affects outcomes.[5][111]​​​​​​ In 2024, the European Society for Vascular Surgery (ESVS) issued a weak recommendation favoring local anesthesia over general anesthesia in elective settings, based on potential reduction in procedure time, ICU admissions, and postoperative hospital stay.[3][112][113][114]​ The IMPROVE multicenter randomized controlled trial detected a significantly reduced 30-day mortality in patients who had EVAR under local anesthesia alone compared with general anesthesia (adjusted OR 0.27, 0.1 to 0.7).[108]​ A separate meta-analysis comparing mode of anesthesia for endovascular repair of ruptured AAA replicated these findings or improved outcomes with EVAR under local anesthesia.[115]​ However, another systematic review did not show any mortality benefit with local anesthesia, but did demonstrate shorter hospital stays.[116] Data from the UK’s National Vascular Registry (9783 patients who received an elective, standard infrarenal EVAR; general anesthetic, n = 7069; regional anesthetic, n = 2347; local anesthetic, n = 367) showed a lower 30 day mortality rate after regional versus general anesthesia.[117] The international multicenter Endurant Stent Graft Natural Selection Global Post-Market Registry (ENGAGE) study examined the outcomes of 1231 patients undergoing EVAR under general (62% of patients), regional (27%), and local (11%) anesthesia.[118]​ The type of anesthesia had no influence on perioperative mortality or morbidity but the use of local or regional anesthesia during EVAR appeared to be beneficial in decreasing procedure time, need for ICU admission, and duration of postoperative hospital stay.[118]​​​

Plus – perioperative antibiotic therapy

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ACUTE
|
ruptured AAA
Plus – 

perioperative antibiotic therapy

Treatment recommended for ALL patients in selected patient group

Antibiotic therapy is indicated for patients undergoing emergency repair of ruptured AAA to cover gram-positive and gram-negative organisms and prevent graft infection.

Broad-spectrum antibiotic coverage is tailored to patient clinical presentation and cultures, and in accordance with local protocols.

Consider – treatment of infectious/inflammatory cause

Back
ACUTE
|
ruptured AAA
Consider – 

treatment of infectious/inflammatory cause

Treatment recommended for SOME patients in selected patient group

Once the patient is stable and urgent surgical repair for the rupture has been prioritized, infectious or inflammatory etiology should be addressed.

If the patient has a suspected infectious aneurysm, early diagnosis and prompt treatment is essential to improve outcomes.[3] Extensive debridement is often needed during urgent surgical repair in these patients. There is a high risk of secondary infective complications and further surgery may be needed for new infectious lesions. Intraoperative cultures should be taken to accurately guide subsequent antibiotic therapy; however, empirical antibiotics are often administered, as peripheral blood cultures and surgical specimen cultures are negative in a large proportion of patients.[5] Prolonged antibiotic therapy (from 4-6 weeks duration to lifelong) may be indicated depending on the specific pathogen, the type of operative repair, and the patient's immunological state​.[3][5]​​​​

Inflammatory aortitis (caused by, for example, Takayasu arteritis or giant cell arteritis) is treated with high-dose corticosteroids and surgery.[5][203]​​​​

symptomatic, but not ruptured AAA

1st line – urgent surgical repair

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ACUTE
|
symptomatic, but not ruptured AAA
1st line – 

urgent surgical repair

In patients with symptomatic aortic aneurysm, urgent repair is indicated regardless of diameter.[5][78]​​[102]​​​​ The development of new or worsening pain may herald aneurysm expansion and impending rupture. Symptomatic, nonruptured aneurysm is, therefore, best treated urgently.[76] Under some circumstances, intervention may be delayed for several hours to optimize conditions to ensure successful repair; these patients should be closely monitored in the intensive care unit.[76]

Endovascular aneurysm repair (EVAR) is increasingly used in the management of patients with symptomatic AAA.[125][126] In observational studies, short-term all-cause mortality rates did not differ between endovascular and open repair of symptomatic AAA.[125][126][127] 

Plus – preoperative cardiovascular risk reduction

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ACUTE
|
symptomatic, but not ruptured AAA
Plus – 

preoperative cardiovascular risk reduction

Treatment recommended for ALL patients in selected patient group

Addressing modifiable cardiovascular risk factors preoperatively improves long-term survival after AAA repair.[194]

Preoperative exercise training reduced postsurgical cardiac complications in a small randomized controlled trial (RCT) of patients undergoing open or endovascular AAA repair, though a Cochrane review and a separate systematic review of prehabilitation (exercise training) prior to AAA surgery did not show any outcome benefit.[195][196][197]​​​ While preoperative exercise training may be beneficial for patients undergoing AAA repair, further investigation with RCTs is needed before it can be recommended more widely.[198]

Perioperative statin use slows aneurysm growth, reduces risk of rupture and, reduces mortality from AAA repair or ruptured AAA.[5]​ Statins should be started at least 1 month before surgery to reduce cardiovascular morbidity and mortality, and continued indefinitely.[3][139]

Patients with AAAs are at increased risk of major adverse cardiovascular events. There is limited evidence, but in the absence of any contraindication, patients with AAA should receive single antiplatelet therapy (aspirin or clopidogrel).[5][140]​​​​ This should be continued during the perioperative period.[3]

Hypertension should be controlled to reduce cardiovascular morbidity and mortality.[3][5]​​​​​

Initiation of beta blockers is not recommended prior to AAA repair.[3]​ However, a beta-blocker can be continued if a patient is already taking this at an appropriate dose.[3]​ Large trials where beta-blockade was started a few days before surgery have indicated no benefit, or even harm, from perioperative beta-blockade.[199][200][201]

Plus – perioperative antibiotic therapy

Back
ACUTE
|
symptomatic, but not ruptured AAA
Plus – 

perioperative antibiotic therapy

Treatment recommended for ALL patients in selected patient group

Perioperative antibiotic therapy is given. Broad-spectrum antibiotic coverage is necessary, in accordance with local protocols.

Consider – treatment of infectious/inflammatory cause

Back
ACUTE
|
symptomatic, but not ruptured AAA
Consider – 

treatment of infectious/inflammatory cause

Treatment recommended for SOME patients in selected patient group

Once the patient is stable and urgent surgical repair for symptomatic AAA has been prioritized, infectious or inflammatory etiology should be addressed.

If the patient has a suspected infectious aneurysm, early diagnosis and prompt treatment is essential to improve outcomes.[3] Extensive debridement is often needed during urgent surgical repair in these patients. There is a high risk of secondary infective complications and further surgery may be needed for new infectious lesions. Intraoperative cultures should be taken to accurately guide subsequent antibiotic therapy; however, empirical antibiotics are often administered, as peripheral blood cultures and surgical specimen cultures are negative in a large proportion of patients.[5] Prolonged antibiotic therapy (from 4-6 weeks duration to lifelong) may be indicated depending on the specific pathogen, the type of operative repair, and the patient's immunological state​.[3][5]​​​​

Inflammatory aortitis (caused by, for example, Takayasu arteritis or giant cell arteritis) is treated with high-dose corticosteroids and surgery.[5][203]​​​​

ONGOING

incidental finding: small asymptomatic AAA

1st line – surveillance

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ONGOING
|
incidental finding: small asymptomatic AAA
1st line – 

surveillance

For AAA detected as an incidental finding, surveillance is preferred to repair until the theoretical risk of rupture exceeds the estimated risk of operative mortality.[4]​​

Early open surgery for the treatment of smaller AAAs does not reduce all-cause or AAA-specific mortality.[4][129]​​​ [ Cochrane Clinical Answers logo ] ​ One systematic review (4 trials, 3314 participants) found high-quality evidence to demonstrate that immediate repair of small AAA (4.0 cm to 5.5 cm) did not improve long-term survival compared with surveillance (adjusted hazard ratio 0.88, 95% CI 0.75 to 1.02, mean follow-up 10 years).[129] The lack of benefit attributable to immediate surgery was consistent regardless of patient age, diameter of small aneurysm, and whether repair was endovascular or open.[129]

Surgical referral of smaller AAA is usually reserved for rapid growth, or once the threshold diameter for aneurysm repair is reached on repeated ultrasonography.[4]

However, in patients with an underlying genetic cause or connective tissue disorder, the threshold diameter for considering repair should be individualized, depending on anatomic features and underlying genetics (rupture risk is higher at smaller aortic diameters in some conditions, and surgical repair is more challenging in certain disorders owing to the increased arterial wall fragility and anatomy).[3]

Plus – aggressive cardiovascular risk management

Back
ONGOING
|
incidental finding: small asymptomatic AAA
Plus – 

aggressive cardiovascular risk management

Treatment recommended for ALL patients in selected patient group

Addressing modifiable cardiovascular risk factors preoperatively improves long-term survival after AAA repair.[194]

Patients should be encouraged to stop smoking and offered drug therapy (nicotine-replacement therapy, nortriptyline, and bupropion) or counseling to assist with this if needed.[1][5][13][15][22][23][134][135][136]​​ [ Cochrane Clinical Answers logo ]

Preoperative exercise training reduced postsurgical cardiac complications in a small randomized controlled trial (RCT) of patients undergoing open or endovascular AAA repair, though a Cochrane review and a separate systematic review of prehabilitation (exercise training) prior to AAA surgery did not show any outcome benefit.[195][196][197]​​​ While preoperative exercise training may be beneficial for patients undergoing AAA repair, further investigation with RCTs is needed before it can be recommended more widely.[198]​

Perioperative statin use slows aneurysm growth, reduces risk of rupture and, reduces mortality from AAA repair or ruptured AAA.[5]​ Statins should be started at least 1 month before surgery to reduce cardiovascular morbidity and mortality, and continued indefinitely.[3][139]​

Patients with AAAs are at increased risk of major adverse cardiovascular events. There is limited evidence, but in the absence of any contraindication, patients with AAA should receive single antiplatelet therapy (aspirin or clopidogrel).[5][140]​​​​ This should be continued during the perioperative period.[3]​

Hypertension should be controlled to reduce cardiovascular morbidity and mortality.[3][5]​​​​​

Consider – treatment of infectious/inflammatory cause

Back
ONGOING
|
incidental finding: small asymptomatic AAA
Consider – 

treatment of infectious/inflammatory cause

Treatment recommended for SOME patients in selected patient group

Infectious or inflammatory etiology should be addressed.

If the patient has a suspected infectious aneurysm, early diagnosis and prompt treatment with antibiotics and urgent surgical repair is essential to improve outcomes.[3] Extensive debridement is often needed during urgent surgical repair in these patients. There is a high risk of secondary infective complications and further surgery may be needed for new infectious lesions. Intraoperative cultures should be taken to accurately guide subsequent antibiotic therapy; however, empirical antibiotics are often administered, as peripheral blood cultures and surgical specimen cultures are negative in a large proportion of patients.[5] Prolonged antibiotic therapy (from 4-6 weeks duration to lifelong) may be indicated depending on the specific pathogen, the type of operative repair, and the patient's immunological state​.[3][5]​​​​

Inflammatory aortitis (caused by, for example, Takayasu arteritis or giant cell arteritis) is treated with high-dose corticosteroids and surgery.[5][203]​​​​

incidental finding: large asymptomatic AAA

1st line – elective surgical repair

Back
ONGOING
|
incidental finding: large asymptomatic AAA
1st line – 

elective surgical repair

Generally, repair is indicated in patients with large asymptomatic AAA (e.g., with a diameter >5.5 cm in men or >5.0 cm in women in the US, although treatment decisions based on greater size may differ in other countries).[78] Repair of aneurysms ≥5.5 cm offers a survival advantage.[1][76][104][105][106]

Decisions regarding repair should be individualized, taking account of patient preference, patient age, sex, perioperative risk factors, and anatomic risk factors. Care should be taken to evaluate patient quality of life, and careful counseling undertaken regarding the risks of surgery and subsequent quality of life. A shared decision making approach taking into account the risks and benefits of the procedures is recommended.[5]​​[129]​​

Data suggest that in patients with large AAAs (≥5.5 cm) undergoing elective repair, EVAR is equivalent to open repair in terms of overall survival, although the rate of secondary interventions is higher for EVAR.[141][142]​ EVAR reduces AAA-related mortality (but not longer-term overall survival) in patients with large AAA (≥5.5 cm) who are unsuitable for open repair.[143]

Post repair, larger AAAs appear to be associated with worse late survival than smaller aneurysms (pooled hazard ratio 1.14 per 1-cm increase in AAA diameter, 95% CI 1.09 to 1.18; 12.0- to 91.2-month follow-up).[144] The association is more pronounced with EVAR than with open repair.

For patients with a complex AAA and standard surgical risk, open or EVAR should be considered based on fitness, anatomy, and patient preference. For patients with a complex AAA and high surgical risk, EVAR with fenestrated and branched technologies should be considered as first-line therapy. Fenestrated and branched endografts have become the treatment of choice of complex AAAs in most high volume centers.[3]​ These procedures are viable alternatives to open repair for juxtarenal and suprarenal AAA, or for those with AAA where a short or diseased neck precludes conventional repair.[3]

Plus – preoperative cardiovascular risk reduction

Back
ONGOING
|
incidental finding: large asymptomatic AAA
Plus – 

preoperative cardiovascular risk reduction

Treatment recommended for ALL patients in selected patient group

Addressing modifiable cardiovascular risk factors preoperatively improves long-term survival after AAA repair.[194]

Patients should be encouraged to stop smoking and offered drug therapy (nicotine-replacement therapy, nortriptyline, and bupropion) or counseling to assist with this if needed.[1][5][13][15][22][23][134][135][136]​​ [ Cochrane Clinical Answers logo ]

Preoperative exercise training reduced postsurgical cardiac complications in a small randomized controlled trial (RCT) of patients undergoing open or endovascular AAA repair, though a Cochrane review and a separate systematic review of prehabilitation (exercise training) prior to AAA surgery did not show any outcome benefit.[195][196][197]​​​ While preoperative exercise training may be beneficial for patients undergoing AAA repair, further investigation with RCTs is needed before it can be recommended more widely.[198]​

Perioperative statin use slows aneurysm growth, reduces risk of rupture and, reduces mortality from AAA repair or ruptured AAA.[5]​ Statins should be started at least 1 month before surgery to reduce cardiovascular morbidity and mortality, and continued indefinitely.[3][139]​

Patients with AAAs are at increased risk of major adverse cardiovascular events. There is limited evidence, but in the absence of any contraindication, patients with AAA should receive single antiplatelet therapy (aspirin or clopidogrel).[5][140]​​​​ This should be continued during the perioperative period.[3]​

Hypertension should be controlled to reduce cardiovascular morbidity and mortality.[3][5]​​​​​

Plus – perioperative antibiotic therapy

Back
ONGOING
|
incidental finding: large asymptomatic AAA
Plus – 

perioperative antibiotic therapy

Treatment recommended for ALL patients in selected patient group

Perioperative antibiotic therapy is given. Broad-spectrum antibiotic coverage is necessary, in accordance with local protocols.

Consider – treatment of infectious/inflammatory cause

Back
ONGOING
|
incidental finding: large asymptomatic AAA
Consider – 

treatment of infectious/inflammatory cause

Treatment recommended for SOME patients in selected patient group

Infectious or inflammatory etiology should be addressed.

If the patient has a suspected infectious aneurysm, early diagnosis and prompt treatment with antibiotics and urgent surgical repair is essential to improve outcomes.[3] Extensive debridement is often needed during urgent surgical repair in these patients. There is a high risk of secondary infective complications and further surgery may be needed for new infectious lesions. Intraoperative cultures should be taken to accurately guide subsequent antibiotic therapy; however, empirical antibiotics are often administered, as peripheral blood cultures and surgical specimen cultures are negative in a large proportion of patients.[5] Prolonged antibiotic therapy (from 4-6 weeks duration to lifelong) may be indicated depending on the specific pathogen, the type of operative repair, and the patient's immunological state​.[3][5]​​​​

Inflammatory aortitis (caused by, for example, Takayasu arteritis or giant cell arteritis) is treated with high-dose corticosteroids and surgery.[5][203]​​​​

endovascular repair leak requiring treatment

1st line – corrective procedure

Back
ONGOING
|
endovascular repair leak requiring treatment
1st line – 

corrective procedure

Endoleak is persistent blood flow outside the graft and within the aneurysm sac.[204][205]​​ It is not a complication following open repair.

Postoperative surveillance can detect major endoleaks and aneurysm sac expansion. Risk following endovascular aneurysm repair (EVAR) is 24%.[204] There are five types of endoleak.[5]

Type I: leak at the attachment site (type IA at the proximal end of the endograft or iliac occluder; type IB at the distal end); usually immediate, but delayed leaks may occur.[Figure caption and citation for the preceding image starts]: Type I endoleak at the distal left iliac anastomosis (leak encircled)University of Michigan/Dr G.R. Upchurch, Departments of Vascular Surgery and Radiology [Citation ends].com.bmj.content.model.Caption@2c441f3c​ Every effort should be made to repair type I endoleak before completing the procedure (e.g., balloon molding of the proximal seal zone, placement of a proximal cuff, endostaples, liquid embolization).[206]​ Persistent type IA endoleak may necessitate conversion to open repair, provided the surgical risk is acceptable.[3][76][207][Figure caption and citation for the preceding image starts]: Extension stent graft deployed for the same type I endoleak (encircled)University of Michigan/Dr G.R. Upchurch, Departments of Vascular Surgery and Radiology [Citation ends].com.bmj.content.model.Caption@3b810b97[Figure caption and citation for the preceding image starts]: Resolution of the type I endoleak resolved after extension deployedUniversity of Michigan/Dr G.R. Upchurch, Departments of Vascular Surgery and Radiology [Citation ends].com.bmj.content.model.Caption@46c91c59

Type II: patent branch leak.[Figure caption and citation for the preceding image starts]: Type II endoleak (encircled) discovered on follow-up computed tomographyUniversity of Michigan/Dr G.R. Upchurch, Departments of Vascular Surgery and Radiology [Citation ends].com.bmj.content.model.Caption@2b0f88d4 Spontaneous resolution may occur, although persistence may result in sac growth.[208] If a type II endoleak or other abnormality of concern is observed on contrast-enhanced CT imaging at 1 month after EVAR, postoperative imaging at 6 months is recommended.[76]​ Around 50% of type II endoleaks are diagnosed before 30 day follow-up; 40% after 30 days, and 8% are diagnosed after 12 months of follow-up.[209] Treatment remains controversial and is advocated either if persistent at 6-12 months or when aneurysm sac size increases such that proximal and/or distal sealing zones may be compromised.[210][211][212][213][214]​​[215] Treatment of choice is transarterial coil embolization, although laparoscopic ligation of collateral branches, direct percutaneous translumbar puncture of the sac, translumbar embolization, and transcatheter transcaval embolization have been reported.[205][210][211][212][216][217][218][219][220]​​[221][222][223][224]​  

Type III: graft defect with leak through fabric tears, graft disconnection, or disintegration of the fabric.[204][205][225] Repair is indicated upon discovery (endovascular stent graft extension).[3][76][211][215][226]​​​

Type IV: leak from graft wall porosity.[204][205] These leaks are uncommon with newer stent grafts and are self-limited.[76][211]​

Type V (endotension): endotension is increased intrasac pressure after EVAR without visualized endoleak on delayed contrast CT scans. less common with the newer-generation grafts.[76] There is no standardized method to measure endotension or consensus on indicated therapy in the absence of aneurysm enlargement; however, treatment of endotension to prevent aneurysm rupture is suggested in selected patients with continued aneurysm expansion.[76][205][215]

Plus – preoperative cardiovascular risk reduction

Back
ONGOING
|
endovascular repair leak requiring treatment
Plus – 

preoperative cardiovascular risk reduction

Treatment recommended for ALL patients in selected patient group

Addressing modifiable cardiovascular risk factors preoperatively improves long-term survival after AAA repair.[194]

Patients should be encouraged to stop smoking and offered drug therapy (nicotine-replacement therapy, nortriptyline, and bupropion) or counseling to assist with this if needed.[1][5][13][15][22][23][134][135][136]​​ [ Cochrane Clinical Answers logo ]

Preoperative exercise training reduced postsurgical cardiac complications in a small randomized controlled trial (RCT) of patients undergoing open or endovascular AAA repair, though a Cochrane review and a separate systematic review of prehabilitation (exercise training) prior to AAA surgery did not show any outcome benefit.[195][196][197]​​​ While preoperative exercise training may be beneficial for patients undergoing AAA repair, further investigation with RCTs is needed before it can be recommended more widely.[198]​

Perioperative statin use slows aneurysm growth, reduces risk of rupture and, reduces mortality from AAA repair or ruptured AAA.[5]​ Statins should be started at least 1 month before surgery to reduce cardiovascular morbidity and mortality, and continued indefinitely.[3][139]​

Patients with AAAs are at increased risk of major adverse cardiovascular events. There is limited evidence, but in the absence of any contraindication, patients with AAA should receive single antiplatelet therapy (aspirin or clopidogrel).[5][140]​​​​ This should be continued during the perioperative period.[3]​

Hypertension should be controlled to reduce cardiovascular morbidity and mortality.[3][5]​​​​​

Plus – perioperative antibiotic therapy

Back
ONGOING
|
endovascular repair leak requiring treatment
Plus – 

perioperative antibiotic therapy

Treatment recommended for ALL patients in selected patient group

Perioperative antibiotic therapy is given. Broad-spectrum antibiotic coverage is necessary, in accordance with local protocols.

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Choose a patient group to see our recommendations

Please note that formulations/routes and doses may differ between drug names and brands, drug formularies, or locations. Treatment recommendations are specific to patient groups. See disclaimer

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