From the Guidelines
The incidence of splenic artery aneurysm rupture is approximately 2-10% of all cases, with higher rupture rates of 20-50% during pregnancy, as reported in the most recent study 1.
Risk Factors and Mortality Rates
The risk factors for rupture include pregnancy (especially third trimester), aneurysm size greater than 2 cm, portal hypertension, liver transplantation, and rapid enlargement.
- The mortality rate from ruptured splenic aneurysms is significant, ranging from 25-70%, with maternal mortality during pregnancy approaching 75% and fetal mortality up to 95% 1.
- Patients with ruptured splenic aneurysms typically present with sudden onset left upper quadrant or epigastric pain, often radiating to the left shoulder (Kehr's sign), along with hemodynamic instability.
Management
Management of ruptured splenic aneurysms requires immediate surgical intervention or endovascular treatment, with interventional radiology with trans-catheter embolisation being the mainstay of treatment in cases of rupture 1.
- For unruptured aneurysms, elective repair is generally recommended for those larger than 2 cm, symptomatic aneurysms, aneurysms in women of childbearing age, and in patients undergoing liver transplantation.
- However, since up to 50% of SAA may rupture at sizes of less than 2 cm, it is difficult to make definitive recommendations on these smaller dilatations, and attention to the presence of SAA in women with severe splenomegaly is appropriate 1.
Key Considerations
- The natural history of splenic artery aneurysms followed up through pregnancy is unknown because no large series of such patients has been collected 1.
- Prophylactic intervention may be appropriate if a known SAA has previously ruptured or if a large aneurysm (>2–3 cm) has been identified pre-conception 1.
From the Research
Incidence of Splenic Aneurysm Rupture
- The incidence of splenic artery aneurysm rupture is a significant concern, with mortality rates as high as 25% 2, 3.
- Pregnancy is often cited as a risk factor for rupture, but a study found that ruptured splenic artery aneurysms are exceedingly rare in pregnant women 4.
- The overall mortality rate for ruptured splenic aneurysms can increase to 75% among pregnant women, with a concomitant fetal mortality of 95% 3.
Risk Factors for Rupture
- Aneurysms with a diameter of more than 2 cm are considered to be at high risk of rupture 5, 2, 6.
- False splenic aneurysms have a greater potential for rupture than true aneurysms due to their faster growth rate 2.
- Other risk factors for rupture include symptoms, enlargement, and detection in pregnancy, childbearing age, or following liver transplantation 5.
Management and Treatment
- Endovascular treatment, such as embolization or stent grafting, is considered the first-line treatment for splenic artery aneurysms due to its minimally invasive nature and lower morbidity and mortality rates compared to surgery 5, 2, 6.
- Surgical treatment is typically reserved for ruptured aneurysms or hemodynamically unstable patients 2, 6.
- Conservative management may be considered for patients with small, asymptomatic aneurysms, but regular imaging is necessary to monitor for changes in size or symptoms 5, 6.