Vascular complications of acute pancreatitis include the following except -
Acute pancreatitis is rarely associated with arterial vascular complications.
MC vessel affected: Splenic artery.
Other vessels: Superior mesenteric, cystic, and gastroduodenal arteries.

Vascular Thrombosis

Pancreatic inflammation can produce vascular thrombosis.
MC affected vessel: Splenic vein.
In severe cases, it can extend into the portal venous system.
Imaging demonstrates splenomegaly, gastric varices, and splenic vein occlusion.
Thrombolytics have been described in the acute early phase.
Most patients can be managed with conservative treatment.
Recurrent episodes of upper gastrointestinal bleeding caused by venous hypertension should be treated with splenectomy.

Pathogenesis
It has been proposed that pancreatic elastase damages the vessels, leading to pseudoaneurysm formation.
Clinical Features

Spontaneous rupture results in massive bleeding.
Clinical manifestations include sudden onset of abdominal pain, tachycardia, and hypotension.

Treatment

If possible, arterial embolization should be attempted to control the bleeding.
Refractory cases require ligation of the affected vessel.
The mortality ranges from 28-56%.
MC affected vessel in acute pancreatitis: Splenic artery (pseudoaneusysm formation).
MC affected vessel leading to vascular thrombosis caused by acute pancreatitis: Splenic vein.
Splenic vein thrombosis
Splenic artery aneurysm
Gastroduodenal artery aneurysm
Middle colic artery thrombosis