Invasive mesenteric angiographic studies
When the diagnosis and treatment of ischemic bowel disease is delayed and peritoneal signs and acidosis ensue, the mortality rate increases significantly.
Angiography is the gold standard for diagnosis of mesenteric arterial occlusion and can help to differentiate between embolic and thrombotic etiologic factors. The cutoff of a major artery in the absence of collateral vessel enlargement is indicative of an embolic cause, whereas vessel narrowing with the development of collaterals signifies thrombosis. Additionally, the venous phase of angiography may demonstrate venous occlusive disease. In NOMI, angiography may demonstrate vessel narrowing or spasm and arterial beading.
Angiography can also be used as a therapeutic modality by selectively infusing vasodilating drugs or thrombolytics, and aiding in the completion of angioplasty, balloon embolectomy, or stent placement. Because of the risks associated with the administration of thrombolytic agents, their use should probably be limited to poor surgical candidates without peritoneal signs, to those in whom the ischemic event is considered to be reversible or of short duration, and to tertiary care centers with technical expertise.
As with all procedures, angiography has associated risks. Atherosclerosis commonly involves the femoral artery, which is usually the site of entry for the angiographic catheter. This makes it harder to access the mesenteric system and can also cause emboli to distant arteries. Furthermore, iodine contrast increases the risk of developing renal insufficiency.
Angiography is the only technique other than exploratory surgery that can establish the diagnosis of and treat mesenteric occlusive disease and NOMI early in the course of the disease.