What is the mortality rate of femoral aneurysms as a cause of death?

Mortality Rate of Femoral Artery Aneurysms

Femoral artery aneurysms are rarely fatal, with rupture occurring in only a small percentage of cases, unlike aortic aneurysms which have significantly higher mortality rates. 1

Epidemiology and Natural History

Femoral artery aneurysms are uncommon vascular entities with a distinct natural history that differs significantly from other arterial aneurysms:

• They represent only a small fraction of peripheral arterial aneurysms
• Unlike abdominal aortic aneurysms (AAAs), the natural history of femoral artery aneurysms is not primarily one of expansion and rupture but rather of thromboembolism or thrombosis 1
• Mortality directly attributable to femoral aneurysms is quite low compared to other aneurysm locations

Risk of Rupture and Death

The risk profile for femoral artery aneurysms shows:

• Rupture rates are approximately 15-46.6% based on available data 2
• This rupture rate is higher than some other peripheral aneurysms but significantly lower than thoracic or abdominal aortic aneurysms
• In a review of femoral artery aneurysm cases, hospital mortality was not registered in a 20-year experience 3
• Mortality is more commonly associated with comorbidities rather than direct aneurysm complications

Comparison with Other Aneurysm Locations

For context, mortality rates from aneurysms in other locations:

• Aortic rupture is found in 0.9% of cases of sudden death 1
• Aortic dissections are present in 62% of these patients, atherosclerotic aneurysms in 37%, and false aneurysms in 1.6% 1
• Ruptures are more common in the ascending aorta (65%) and less frequent in the abdominal aorta (32%) 1
• Fusiform thoracic aortic aneurysms have a higher rupture risk (61%) compared to abdominal aortic aneurysms 1

Associated Conditions and Risk Factors

Femoral artery aneurysms rarely occur in isolation:

• 48-85% of patients with femoral aneurysms have additional aneurysms in other locations 3, 1
• Coexistent abdominal aortic aneurysms have been reported in 85% of patients with femoral aneurysms 1
• Bilateral femoral aneurysms occur in approximately 26-50% of cases 3
• Hypertension is the main risk factor, present in 85% of patients with ruptured aneurysms 1

Management Considerations

The ACC/AHA guidelines recommend:

• Patients with symptomatic femoral artery aneurysms should undergo repair (Class I recommendation) 1
• Surveillance by annual ultrasound imaging is suggested for patients with asymptomatic femoral artery true aneurysms smaller than 3.0 cm in diameter (Class IIa recommendation) 1
• Surgical repair has good outcomes with low complication rates, and amputation is relatively rare (6.6%) 2

Clinical Implications

When managing patients with femoral artery aneurysms:

• The primary focus should be on preventing thromboembolism rather than preventing rupture
• Screening for other aneurysms, particularly abdominal aortic aneurysms, is essential
• Regular surveillance with ultrasound is appropriate for small, asymptomatic aneurysms
• Surgical intervention has favorable outcomes with low mortality rates

In summary, while femoral artery aneurysms can cause morbidity through thromboembolism, they are rarely a direct cause of death compared to aneurysms in other locations such as the aorta.