Page 311 - Libro 2

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The Mesenteric Arteries
Anne M. Musson, Jack I. Siegel, and Robert M. Zwolak
OBJECTIVES
Describe typical symptoms of chronic mesenteric ischemia
List the vessels for which the Intersocietal Commission for the Accreditation of Vascular Laboratories (ICAVL) requires documentation
Describe a collateral pathway of blood flow to the hepatic and splenic arteries when the celiac artery is occluded
Describe the differences in Doppler waveform characteristics between the celiac and superior mesenteric arteries
Define compensatory flow
List indications other than chronic mesenteric ischemia for mesenteric artery duplex
Define median arcuate ligament compression syndrome
KEY TERMS
celiac artery | inferior mesenteric artery | mesenteric ischemia | postprandial | splanchnic | superior mesenteric artery | visceral
GLOSSARY
collateral flow relating to additional blood vessels that aid or add to circulation
postprandial occurring after a meal
The mesenteric duplex examination is a widely ac- cepted and accurate test to identify stenosis or oc- clusion in the mesenteric arteries. Less common indications for this study include the identification of aneurysms and dissections of the visceral arteries and the evaluation of patients with suspected median ar- cuate ligament compression syndrome. Patients with abnormal findings may require open surgical or percu- taneous endovascular repair, and another excellent ap- plication of this noninvasive test is to monitor patients following these procedures for patency and restenosis.
The most common application in the noninva- sive vascular laboratory is evaluation of the celiac and superior mesenteric arteries (SMAs) for chronic mesenteric ischemia. Attempts should be made to vi- sualize the inferior mesenteric artery (IMA) as well. The diagnosis of chronic mesenteric ischemia is dif- ficult because the disorder is rare and the symptoms are nonspecific, so it is often overlooked for pro- longed periods of time as the patient is worked up
splanchnic relating to or affecting the viscera visceral relating to internal organs or blood
vessels in the abdominal cavity
for malignancy, ulcer, gallbladder, and psychological etiologies. Duplex ultrasound remains a reliable nonin- vasive test to identify pathologic blood flow patterns in patients with chronic mesenteric ischemia. Although symptomatic mesenteric ischemia is rare, atheroscle- rotic stenosis or occlusion of the visceral arteries is not uncommon. In one study, 27% of patients undergoing aortic angiography for the evaluation of aortic aneu- rysm or lower extremity arterial occlusive disease were found to have 􏰀50% stenosis of either the celiac or the superior mesenteric arteries.1 The duplex examination holds an advantage over computed tomography (CT) or computed tomography angiography (CTA) in that the duplex examination provides physiological infor- mation about a stenosis. Only a small fraction of these patients develop chronic intestinal ischemia because these arteries are interconnected by a rich collateral network. It is in patients with extensive disease involv- ing two or all three of these vessels that symptoms generally develop and can become life threatening.
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