Splenic artery aneurysms (SAAs) are a rare but potentially fatal condition that warrant serious attention. While small SAAs are often asymptomatic and discovered incidentally, larger aneurysms can lead to life-threatening complications if left untreated. Understanding the dangers of SAAs is crucial for timely diagnosis and appropriate management to prevent devastating outcomes.
Risk of Rupture
The primary concern with SAAs is the risk of rupture, which can lead to massive internal bleeding and hemodynamic instability. Studies have shown that the rupture rate for true aneurysms is relatively low (2-3%), but this risk increases significantly for pseudoaneurysms (37-47%) with a mortality rate of up to 90%.
Rupture Location and Consequences
When an SAA ruptures, it can lead to bleeding into the peritoneal cavity, pancreatic duct, stomach, colon, retroperitoneum, or even the pancreatic cyst. Rupture into the stomach, known as hemosuccus pancreaticus, is a rare but serious complication that can cause massive lower gastrointestinal bleeding.
Ruptured SAAs can also lead to life-threatening complications such as hypovolemic shock, which requires immediate fluid resuscitation and surgical intervention. The maternal mortality rate for ruptured SAAs during pregnancy is alarmingly high at 75%, with fetal mortality reaching up to 95%.
Risk Factors and Predictors
Several factors can increase the risk of SAA rupture, including portal hypertension, pregnancy, and the size of the aneurysm. Studies have shown that SAAs larger than 2 cm in diameter are more likely to rupture. Additionally, the location of the aneurysm within the splenic artery can also affect the risk, with proximal aneurysms being more challenging to manage.
Certain anatomical features, such as a tortuous and angulated splenic artery, may also contribute to the development and expansion of SAAs. Calcification of the aneurysm wall, known as “eggshell,” can offset some risk factors but does not completely eliminate the danger of rupture.