Visceral pseudoaneurysms due to pancreatic pseudocysts: rare but lethal complications of pancreatitis.

OBJECTIVE: Erosion of pancreatic pseudocysts into adjacent vessels is a rare but highly lethal cause of intra-abdominal hemorrhage. Percutaneous angiographic embolization (PAE) of the bleeding artery has recently been advocated as the preferred therapy. This study was undertaken to survey the outcome after treatment of this complication and to make recommendations for its management.

METHODS: An 11-year retrospective analysis was performed of all patients treated at a large tertiary care referral center for visceral artery pseudoaneurysms associated with pancreatic pseudocysts.

RESULTS: From 1988 to 1998, 256 patients were admitted for complications of pancreatic pseudocysts. Sixteen patients (11 men and 5 women) were identified in whom a pseudocyst had eroded into a major blood vessel with hemorrhage or development of a false aneurysm. The mean age was 45 years (range, 23-67 years). Active bleeding was present in 13 patients, whereas three had evidence of recent hemorrhage. Ten of 16 patients initially underwent operative therapy, four elective and six emergency, whereas six stable patients were initially treated with PAE. Technical failures of the initial treatment or secondary complications required both therapeutic modalities in six patients, which resulted in 13 total surgical interventions and 10 PAEs. The surgical morbidity rate was 62% (8 of 13), whereas that of PAE was 50% (5 of 10). Three deaths occurred after emergency operations, two of which failed to stop the bleeding, accounting for all of the deaths in the series (3 [19%] of 16). A trend was noted toward increased death with necrotizing pancreatitis (P =.07) and emergency surgery (P =.06). Ranson's criteria were not found to be predictive of death in this series. Surgical drainage procedures were required in seven (44%) of 16 patients for infections (n = 3) or mass effect of the pseudoaneurysm (n = 3). The mean size of pseudoaneurysms that required operative intervention for secondary complications was 13.9 cm, compared with 7.7 cm for all others in the series (P =.046). Long-term follow-up was available in all 13 survivors at a mean of 44 months (range, 1-108 months).

CONCLUSIONS: The management of pancreatic pseudocyst-associated pseudoaneurysms remains a challenging problem with high morbidity and death rates. Operation and PAE play complementary management roles. PAE is recommended as the initial therapy for hemodynamically stable patients. Surgery should be reserved for actively bleeding, hemodynamically unstable patients; for failed embolization; and for other secondary complications such as infection or extrinsic compression.