Stent Placement for Spontaneous Isolated Superior ... - TSOC

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Case Report

Acta Cardiol Sin 2010;26:268-71

Stent Placement for Spontaneous Isolated Superior Mesenteric Artery Dissection via Radial Approach with Intravascular Ultrasound Assistance Max Woo, Hisham Hussein, Hsiu-Yu Fang and Chiung-Jen Wu

Spontaneous isolated superior mesenteric artery (SMA) dissection was a sporadically reported vascular event, but an increasing number of case reports have been published in recent years. The optimal therapy opinions are widely divided. Despite there still being no consensus on the best treatment, an increasing number of patients in recent years have been reported to be treated successfully by non-surgical rather than surgical approaches. Here, we present a 47-year-old man with SMA dissection, who received percutaneous stent placement. According to our experience, successful stent placement would be achieved more easily by radial approach and intravascular ultrasound (IVUS) assistance.

Key Words:

Dissection · Intravascular ultrasound · Radial approach · Superior mesenteric artery

INTRODUCTION

persistent abdominal symptoms, percutanous endovascular treatment was performed via radial approach with intra-vascular ultrasound (IVUS) assistance.

Spontaneous isolated superior mesenteric artery (SMA) dissection is a rare cause of acute mesenteric ischemia but might be fatal. This condition was first described in the literature in 1947. There are three treatment approaches: conservative (with or without anticoagulation), surgery and endovascular repair. Optimal treatment remains controversial at present. To prevent bowel necrosis, a right time to perform intervention and a proper process to accomplish the procedure are what we intend to look for. This article reports one case of spontaneous isolated SMA dissection. In order to relieve

CASE REPORT A 47-year-old man presented to our emergency department because of abdominal fullness for one day. He had been in good health except for history of left renal stone. He denied hypertension, diabetes mellitus, hyperlipidemia or any recent abdominal trauma. On arrival, the initial physical examination showed epigastric tenderness. Due to prolonged pain, abdominal CT was done and revealed superior mesenteric artery dissection (Figure 1A). After prescription of pain killer, tenderness was temporarily relieved. In the following 3 days, his symptoms recurred persistently. We therefore performed percutaneous endovascular stenting for SMA dissection via left high radial artery approach. The angiogram disclosed an aneurysm formation nearby the SMA ostium, and IVUS revealed an intimal flap corresponding to a

Received: March 25, 2010 Accepted: July 27, 2010 Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital - Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung, Taiwan. Address correspondence and reprint requests to: Dr. Chiung-Jen Wu, Division of Cardiology, Kaohsiung Chang Gung Memorial Hospital, No. 123, Ta-Pei Road, Niaosung, Kaohsiung 83301, Taiwan. Tel: 886-7-731-7123 ext. 2363; Fax: 886-7-731-7123 ext. 2355; E-mail: [email protected]


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deployed to cover the SMA orifice and overlap with the abovementioned Wallstent. During procedure, the stent balloon was used to dilate the in-stent portion of Wallstent (Figure 2A). Final angiogram and Volcano IVUS confirmed a good result of the stent landing and expansion. (Figures 2B&C). The patient was discharged 3 days after the procedure, maintained on aspirin and

narrow segment on the angiogram (Figures 1B&C). A Wallstent (10 mm in diameter and 31 mm in length) was deployed to cover the dissected portion through a 7Fr Kimney guiding catheter (100 cm). In order to cover the aneurismal segment between the SMA orifice and the dissected segment, an Express SD stent (balloon expandable stent, 7 mm in diameter and 19 mm in length) was

B

A

C

Figure 1. (A) Abdominal CT with contrast in cross-section view revealed SMA dissection (white arrow). (B) Selective angiogram of SMA via left high radial approach with 7F Kimney guiding catheter showed aneurismal dilatation from the SMA ostium followed by narrow lumen. (C) IVUS disclosed that an intimal flap (white arrow) brought about true lumen and false lumen which was corresponding to a narrow portion on the angiogram.

A

B

C

Figure 2. (A) After express SD stent deployment, the stent balloon was used for Wallstent dilatation. (B) IVUS disclosed apposite stent position. (C) Angiography after deployment of two stents for the dissection revealed widened true lumen and complete recanalization of the SMA. 269


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mainstay modality, particularly in patients presenting with a sign of bowel necrosis or impending rupture. Several surgical approaches were reported, such as bowel resection, direct arterial repair, venous or prosthetic grafts, etc.6 Unfortunately, surgery has generally been accompanied with a variety of complications. Spontaneous SMA dissection was viewed as self-limited disease in the absence of persistent abdominal pain.6,7 Although conservative treatment keeps patient away from hazard of invasive treatment, there is still a dispute about the administration of anticoagulation therapy. Yun et al.7 suggested that anticoagulation could prevent false lumen thrombosis, but also promote further dissection propagation. In our opinion, anticoagulation therapy should not be given to those patients with SMA dissection who are being treated conservatively. The major cause of death in SMA dissection is bowel necrosis.9 The most important aim of treatment for SMA dissection is symptom relief and prevention of bowel necrosis. These can be achieved by early percutaneous endovascular treatment when surgical indication is not matched yet but there is high index of suspicion of disease progression. According to report of Yun et al., 7 dissection length is positively associated with more severe clinical symptoms. Theoretically, longer dissection length contributes to higher incidence of bowel ischemia and subsequent necrosis. We postulate that if there are persistent abdominal symptoms, stent placement for SMA dissection without branch involvement is a practical approach in order to stop disease progression and deterioration of patients clinical condition. To our knowledge, this case is the first and only patient who received SMA stent placement via radial approach. Here we address three advantages of radial artery approach: 1. On account of superior take-off of the SMA orifice, it is easier to engage the orifice from above than below. 2. Engagement from above provides easier stent deployment because it supplies a more stable guiding system by taking shape with a smaller angle over the orifice for stent to pass. 3. Major bleeding rate is reduced and allows earlier ambulation, in contrast to femoral artery approach. Nevertheless, radial artery approach has inevitable disadvantages: 1. A lengthened guiding catheter is demanded due to the longer distance between the SMA orifice and radial artery. 2. For a minority of patients, tortuous, stenotic or spastic vessels

clopidogrel simultaneously for 3 months and then aspirin alone thereafter. He remained asymptomatic during 5 months’ follow-up.

DISCUSSION Isolated spontaneous SMA dissection is a sparse vascular event. It’s a rare condition with poor prognosis if early diagnosis and proper management are not given. This rare vascular event has a characteristic of difficult diagnosis and is likely to be neglected. Most of the published cases presented with abdominal pain or other gastrointestinal symptoms, such as nausea, vomiting or abdominal fullness. Therefore, most SMA dissections were diagnosed accidentally by contrast-enhanced abdominal CT scan. According to literature review, the postmortem incidence in a series of 6666 autopsies was 0.06%.1 The superior mesenteric artery is the second most frequent peripheral artery after the internal carotid artery to be affected by spontaneous dissection.2 Bauersfeld et al. reported the first case in 1947,3 and recently, an increasing number of case reports has been published due to the tendency to use abdominal CT scan for patients presenting with acute abdomen of unknown etiology.4,5 In contrast to the well-known correlation between hypertension and aortic dissection, the etiology of spontaneous isolated SMA dissection remains a riddle. Recently published cases were predominantly male, over forty years of age.6,7 Even though there is no sufficient evidence to suggest smoking and hypertension as the main causes of SMA dissection, they are reported as predisposing factors for developing this serious condition; however, the majority of recorded cases were generally healthy. According to the report of Sparks et al., the typical dissection entry point is usually located at 1~6 cm distal to the orifice of SMA (mean 2.6 cm). 8 This segment is a transition zone of the SMA from a fixed segment under the pancreas to the mobile segment at the mesenteric root. Yun et al.7 suggested that because the transition point could be the focus of intimal tear under abnormal sheering stress, the convex-curved run of the SMA might provide a mechanical factor that initiates SMA dissection. Optimal treatment for isolated SMA dissection is still controversial. Currently, the surgical option is the Acta Cardiol Sin 2010;26:268-71

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In conclusion, we have provided this case to illustrate that even though optimal treatment strategy for this rare condition is uncertain, based on our experience and literature review, conservative therapy without anticoagulation can be efficient in an asymptomatic patient. If there is persistent dissection-related symptom or sign, percutaneous endovascular stent placement should be done early for bowel salvage. High left radial artery approach deserves to be the first option due to its multiple merits, and IVUS assistance provides flawless deployment of stent and promotes long-term stent patency.

make radial approach impossible. 3. Radial artery size should be large enough to accommodate a 7F guiding catheter. However, with advancement of material technology, lengthened guiding catheter with smaller profile is now available. Given the experience regarding with renal artery stenting in our center,10 the guiding catheter (100 cm) is too short to reach renal artery orifice via traditional radial approach, particularly if right-sided, with higher incidence of subclavian and/or innominate artery tortuousity in the elderly, or in patients with body height over 170 cm. So we prefer the high left radial approach (10~15 cm above the styloid process), otherwise a special order of guiding catheter over 110 cm is recommended. As long as the orifices of the renal artery and SMA are closely related anatomically, we presume that left high radial approach is applicable in SMA stenting. Considering on the procedure difficulty and post procedure wound care, left high radial artery approach deserves to be the first option. To our knowledge, there are a lot of applications of IVUS.11,12 Nevertheless, so far as available literature is concerned, our case is the first reported application of intra-vascular ultrasound in SMA dissection. IVUS provided more accurate information about dissection length and entry point in contrast to CT scan and angiogram. The aims of stent placement are to prevent extension of dissection and ensure adequate bowel blood perfusion without thrombus formation in SMA. These purposes can be achieved by precise coverage of the entry point and obliteration of false lumen. In this case, we chose the self-expandable stent to cover distal dissected segment because self-expandable stent is more flexible than balloon-expandable stent. The flexibility of self-expandable stent made stent deployment to the distal portion easy. Nevertheless, in order to cover the orifice precisely, we chose the balloon-expandable stent because stent shortening after deployment rarely happens to balloon-expandable stents. IVUS-guided approach can ensure flawless deployment of stent and promote long-term stent patency. Furthermore, adequate anti-platelet therapy is supposed to have benefit for long-term stent patency too. However, there is still no consensus about duration of anti-platelet therapy after SMA stenting. Hence, in this case, we advised anti-platelet therapy for peripheral artery occlusive disease, for which dual-antiplatelet agent for at least three months is recommended.

REFERENCES 1. Foord AG, Lewis RD. Primary dissecting aneurysms of peripheral and pulmonary arteries: dissecting hemorrhage of media. Arch Pathol 1959;68:553-7. 2. Leung DA, Schneider E, Kubik-Huch R, et al. Acute mesenteric ischemia caused by spontaneous isolated dissection of the superior mesenteric artery: treatment by percutaneous stent placement. Eur Radiol 2000;10:1916-9. 3. Bauersfeld SR. Dissecting aneurysm of the aorta: a presentation of fifteen cases and a review of recent literature. Ann Intern Med 1947;26:873-89. 4. Wu XM, Wang TD, Chen MF. Percutaneous endovascular treatment for isolated spontaneous superior mesenteric artery dissection. Catheter Cardiovasc Interv 2009;73:145-51. 5. Casella IB, Bosch MA, Sousa WO Jr. Isolated spontaneous dissection of the superior mesenteric artery treated by percutaneous stent placement: case report. J Vasc Surg 2008;47:197-200. 6. Morris JT, Guerriero J, Sage JG, et al. Three isolated superior mesenteric artery dissections: update of previous case reports, diagnostics, and treatment options. J Vas Surg 2008;47:649-53. 7. Yun WS, Kim YW, Park KB, et al. Clinical and angiographic follow-up of spontaneous isolated superior mesenteric artery dissection. Eur J Vasc Endovasc Surg 2009;37:572-7. 8. Sparks SR, Vasquez JC, Bergan JJ, et al. Failure of nonoperative management of isolated superior mesernteic artery dissection. Ann Vasc Surg 2000;14:105-9. 9. Tsai JL, Wu YL, Lin HJ. Spontaneous superior mensenteric artery (SMA) dissection. J Emerg Med 2008;35:81-2. 10. Hung WC, Wu CJ, Fang CY, et al. Transradial approach for renal artery angioplasty and stenting in Chinese patients: single center experience. Acta Cardiol Sin 2006;22:8-15. 11. Wu CC, Fang HY, Wu CJ. Salvage for long-tract false lumen dissection via IVUS guidance in CTO lesions. Acta Cardiol Sin 2009;25:226-8. 12. Lin WH, Tsai JP, Wang KT, et al. Intravascular ultrasound helps differentiate coronary mural hematoma from dissection. Acta Cardiol Sin 2009;25:39-42. 271
