**7. Treatment of mesenteric venous thrombosis**

Initial anticoagulation with heparin is the treatment of choice in patients without peritonitis. After initial anticoagulation, continued treatment with low-molecular-weight heparin (LMWH) or VKA is advocated. Uncertainties about bowel viability are assessed through laparotomy or laparoscopy; it is safer to perform a laparotomy to check for bowel viability in patients with signs of peritonitis and rebound tenderness. Endovascular treatment in combination with heparin infusion, with or without bowel resection, is an additional treatment tool (23, 24, 25, 26, 27). The indications for surgery are peritonitis, severe gastrointestinal bleeding, late small bowel perforation, and intestinal stricture; the last is often associated with chronic diarrhea.

## **7.1 Splanchnic artery aneurysms**

True aneurysms of splanchnic arteries are less common than visceral artery pseudoaneurysms, but they remain an important vascular disease. Nearly 22% of these present as clinical emergencies, including 8.5% that result in death (28). The pathogenesis and natural history of these aneurysms have been reassessed, and in most instances redefined, within the past three decades as advances in imaging technology and endovascular treatments have begun to influence diagnostic and management strategies. Recognition of splanchnic artery aneurysms has increased because of the greater availability and widespread use of advanced imaging capabilities such as high-resolution computed tomography (CT) scanning, magnetic resonance angiography (MRA), sophisticated ultrasonography, and angiography. Selective arteriography remains the most valuable examination in planning therapy but noninvasive imaging techniques for diagnosis and operative planning are becoming increasingly important.

Although surgery remains the mainstay of therapy for most splanchnic aneurysms, especially in the setting of rupture, many aneurysms (particularly those involving solid organs) are now treated with catheter-based interventions. Endovascular approaches are

Initial anticoagulation with heparin is the treatment of choice in patients without peritonitis. After initial anticoagulation, continued treatment with low-molecular-weight heparin (LMWH) or VKA is advocated. Uncertainties about bowel viability are assessed through laparotomy or laparoscopy; it is safer to perform a laparotomy to check for bowel viability in patients with signs of peritonitis and rebound tenderness. Endovascular treatment in combination with heparin infusion, with or without bowel resection, is an additional treatment tool (23, 24, 25, 26, 27). The indications for surgery are peritonitis, severe gastrointestinal bleeding, late small bowel perforation, and intestinal stricture; the last is

True aneurysms of splanchnic arteries are less common than visceral artery pseudoaneurysms, but they remain an important vascular disease. Nearly 22% of these present as clinical emergencies, including 8.5% that result in death (28). The pathogenesis and natural history of these aneurysms have been reassessed, and in most instances redefined, within the past three decades as advances in imaging technology and endovascular treatments have begun to influence diagnostic and management strategies. Recognition of splanchnic artery aneurysms has increased because of the greater availability and widespread use of advanced imaging capabilities such as high-resolution computed tomography (CT) scanning, magnetic resonance angiography (MRA), sophisticated ultrasonography, and angiography. Selective arteriography remains the most valuable examination in planning therapy but noninvasive imaging techniques for diagnosis and

Although surgery remains the mainstay of therapy for most splanchnic aneurysms, especially in the setting of rupture, many aneurysms (particularly those involving solid organs) are now treated with catheter-based interventions. Endovascular approaches are

Fig. 6. Retrograde aortoceliac–superior mesenteric artery bypass

**7. Treatment of mesenteric venous thrombosis** 

operative planning are becoming increasingly important.

often associated with chronic diarrhea.

**7.1 Splanchnic artery aneurysms** 

commonly used to control the bleeding that accompanies aneurysm rupture (29), and prophylactic treatment of incidentally discovered intact aneurysms has become common (particularly those well-collateralized aneurysms that are imbedded within the pancreatic or hepatic parenchyma). Embolization has become the preferred treatment in patients at high surgical risk or for aneurysms in locations that are difficult to approach surgically.


Table 1. Incidence of Aneurysms of the Splanchnic Arterial Circulation (30, 31)

## **7.2 Splenic artery aneurysm**

The most common of the splanchnic artery aneurysms and account for as many as 60% of all reported splanchnic aneurysms (32). The most common clinical risk factors reported in association with Splenic Artery Aneurysm are female gender, a history of multiple pregnancies, and portal hypertension. A classic calcified ring may be noted in the left upper quadrant on a plain x-ray film of the abdomen.the patients may have an abdominal bruit, the majority of physical examinations are normal in patients with asymptomatic lesions. When rupture occurs, patients usually complain of acute left-sided abdominal pain. Shock, abdominal distention, and death can result from free intraperitoneal rupture of an Splenic Artery Aneurysm. The overall mortality of ruptured Splenic Artery Aneurysm is high (33).

Splenic aneurysms that have ruptured or are symptomatic require urgent treatment. Additionally, aneurysms in pregnant women or those of childbearing age also absolutely warrant treatment. Less stringent indications for treatment include aneurysms that are noted to be enlarging or those greater than 2 cm in diameter.

Endovascular exclusion of has been used more recently with general success. Treatment options include coil embolization of the splenic artery both proximal and distal to the aneurysm itself, thereby effectively "trapping" the lesion (34, 35).

#### **7.3 Hepatic artery aneurysms**

The hepatic artery is the second most common location for aneurysmal degeneration in the splanchnic circulation. The causes are degenerative ("atherosclerotic"), medial degeneration,

Mesenteric Vascular Disease 245

[1] Rosenblum JD, Boyle CM, Schwartz LB: The mesenteric circulation: anatomy and

[2] Foley MI, Moneta GL, Abou-Zamzam AM, et al: Revascularization of the superior

[5] Park WM, Gloviczki P, Cherry Jr KJ, et al: Contemporary management of acute

[6] Bradbury AW, Brittenden J, McBride K, et al: Mesenteric ischaemia: a multidisciplinary

[9] Thomas JH, Blake K, Pierce GE, et al: The clinical course of asymptomatic mesenteric

[10] Kumar S, Sarr MG, Kamath PS: Mesenteric venous thrombosis. N Engl J Med 2001;

[13] Sivamurthy N, Rhodes JM, Lee D, et al: Endovascular versus open mesenteric

[14] Sharafuddin MJ, Olson CH, Sun S, et al: Endovascular treatment of celiac and mesenteric arteries stenosis: applications and results. J Vasc Surg 2003; 38:692-698. [15] Sarac TP, Altinel O, Kashyap V, et al: Endovascular treatment of stenotic and occluded visceral arteries for chronic mesenteric ischemia. J Vasc Surg 2008; 47:485-491. [16] Brown DJ, Schermerhorn ML, Powell RJ, et al: Mesenteric stenting for chronic

[17] Lau H, Chew DK, Whittemore AD, et al: Transaortic endarterectomy for primary mesenteric revascularization. Vasc Endovasc Surg 2002; 36:335-341. [18] Jimenez JG, Huber TS, Ozaki K, et al: Durability of antegrade synthetic aortomesenteric bypass for chronic mesenteric ischemia. J Vasc Surg 2002; 35:1078-1084. [19] Kansal N, LoGerfo FW, Belfield AK, et al: A comparison of antegrade and retrograde

[20] Kougias P, Lau D, El Sayed HF, et al: Determinants of mortality and treatment outcome

[21] Mateo RB, O'Hara PJ, Hertzer NR, et al: Elective surgical treatment of symptomatic

[22] Mitsuyoshi A, Obama K, Shinkura N, et al: Survival in nonocclusive mesenteric

following surgical interventions for acute mesenteric ischemia. J Vasc Surg 2007;

chronic mesenteric occlusive disease: early results and late outcomes. J Vasc Surg

ischemia: early diagnosis by multidetector row computed tomography and early

revascularization: immediate benefits do not equate with short-term functional

[11] Schwartz LB, Gewertz BL: Mesenteric ischemia. Surg Clin North Am 1997; 77:275-507. [12] Dietrich CF, Jedrzejczyk M, Ignee A: Sonographic assessment of splanchnic arteries and

[7] Mansour MA: Management of acute mesenteric ischemia. Arch Surg 1999; 134:328-330. [8] Oldenburg WA, Lau LL, Rodenburg TJ: Acute mesenteric ischemia: a clinical review.

[3] Stoney RJ, Cunningham CG: Acute mesenteric ischemia. Surgery 1993; 114:489-490. [4] McKinsey JF, Gewertz BL: Acute mesenteric ischemia. Surg Clin North Am 1997; 77:307-

mesenteric artery alone for treatment of intestinal ischemia. J Vasc Surg 2000; 32:37-

mesenteric ischemia: factors associated with survival. J Vasc Surg 2002; 35:445-452.

physiology. Surg Clin North Am 1997; 77:289-306.

approach. Br J Surg 1995; 82:1446-1459.

Arch Intern Med 2004; 164:1054-1062.

arterial stenosis. J Vasc Surg 1998; 27:840-844.

the bowel wall. Eur J Radiol 2007; 64:202-212.

mesenteric ischemia. J Vasc Surg 2005; 42:268-274.

mesenteric bypass. Ann Vasc Surg 2002; 16:591-596.

outcomes. J Am Coll Surg 2006; 202:859-

**8. References** 

47.

318.

345:1683-1688.

46:467-474.

1999.821-832.

fibrodysplasia, trauma, infection, biliary diseases and percutaneous or endoscopic procedures, polyarteritis nodosa, and congenital disorders.

Fig. 7. Splenic Artery Aneurysm (intraoperative photograph)

Symptoms can include epigastric or right upper quadrant pain and subsequent gastrointestinal hemorrhage and jaundice. Treatment options depend to a large extent on the anatomic location and morphology of the Hepatic Artery Aneurysms, underlying etiology, and status of the end organ (36, 37, 38, 39).

#### **7.4 Celiac artery aneurysms**

In contrast to Splenic Artery Aneurysms are Celiac Artery Aneurysms more commonly found in men. The causes are medial degeneration or atherosclerotic disease. Less common causes include trauma, collagen vascular disease, arterial dissection, anomalous splanchnic circulation, and mycotic aneurysms. Open surgical options included aneurysmectomy, aneurysmorrhaphy, and ligation (40).
