Case Report Emergency Endovascular Management of a Symptomatic Pseudoaneurysm of the Left Subclavian Artery Ostium Using a Combination of an Abdominal Aortic Stent-Graft Extension Cuff and a Periscope Stent Graft Diego Caicedo Valdes,1 Christos D. Karkos,2 Juan Carlos Moy Petersen,3 Julia Requena Fern andez,1 and Rodrigo Fernandez Gonzalez,1 Pontevedra and Santa Cruz de Tenerife, Spain, and Thessaloniki, Greece
A pseudoaneurysm located at the subclavian artery ostium is an infrequent but life-threatening pathology that usually requires major thoracic surgery with a high risk of mortality and morbidity. Endovascular therapy applied to the aortic arch branches is a recent alternative technique, which is still in its early stages because dedicated endovascular devices for the aortic arch are lacking. In this article, we present the emergency endovascular management of a symptomatic pseudoaneurysm of the left subclavian artery ostium which was presumably secondary to an atherosclerotic plaque rupture. Endovascular exclusion required a combination of an abdominal aortic stent-graft extension cuff, which was placed via a retroperitoneal iliac access, and a subclavian artery periscope stent graft.
Isolated subclavian artery aneurysms are infrequent lesions. Aneurysms related to atherosclerosis, trauma, thoracic outlet syndrome, infection,
Presented as an abstract at the 10th International Symposium on Endovascular Therapeutics (SITE), May 8e11, 2013, at Barcelona, Spain. Funding: This case report did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. 1
Angiology and Vascular Surgery Department, Complexo Hospitalario de Pontevedra, Pontevedra, Spain. 2 Vascular Surgery Unit, 5th Department of Surgery, Medical School, Aristotle University of Thessaloniki, Thessaloniki, Greece. 3 Angiology and Vascular Surgery Department, Hospital Nuestra Se~ nora de la Candelaria, Santa Cruz de Tenerife, Spain.
Correspondence to: Diego Caicedo Valdes, Angiology and Vascular Surgery Department, Complexo Hospitalario de Pontevedra, Avda de Montecelo, s/n 36071 Pontevedra, Spain; E-mail:
[email protected] Ann Vasc Surg 2018; -: 1.e1–1.e5 https://doi.org/10.1016/j.avsg.2018.06.033 Ó 2018 Elsevier Inc. All rights reserved. Manuscript received: March 9, 2018; manuscript accepted: June 21, 2018; published online: - - -
congenital arterial anomalies, and aberrant left subclavian artery (Kommerell’s diverticulum) have all been previously described.1e6 An atherosclerotic plaque ruptureerelated symptomatic pseudoaneurysm at the left subclavian artery ostium is an extremely rare and potentially life-threatening pathology. Such a condition represents a surgical challenge due to the difficult surgical access and the emergency scenario. A major thoracic surgery is usually required to treat these lesions and carries a significant risk for mortality and morbidity, particularly in the elderly patients or those with serious cardiorespiratory or renal comorbidities. The endovascular therapy in the thoracic aorta offers a less invasive alternative treatment. Obviously, this therapy has limitations in the aortic arch because of the need to maintain perfusion of the arch branches. Fenestrated endografts have emerged to solve this problem, but the main limitations are the high cost and lack of availability for urgent cases. Chimney stent-graft techniques have been used to extend 1.e1
1.e2 Case Report
the sealing zone during aortic stent grafting in selected cases with encouraging results.7e11 However, larger experiences are needed, and information concerning the durability of these procedures is lacking. Reverse chimney or periscope technique is a modification of the chimney technique in which the flow to the target vessel goes in a reverse way.10 The main drawback of these techniques at aortic arch level is the risk of type I (‘‘gutter’’) endoleak and stroke, problems which are currently to be minimized with improved technology. In this report, we present the emergency endovascular management of a symptomatic pseudoaneurysm of the left subclavian artery ostium, which was secondary to an atherosclerotic plaque rupture, and also review the existing literature on the topic.
CASE REPORT A 70-year-old man presented to the emergency department of our hospital with a 48-hour history of chest pain, which was not responding to conventional analgesics. His past medical history revealed hypertension and that he was an ex-smoker. Upon arrival, the patient was stable, but in severe pain, which was not affected by the respiratory movements. He denied any previous trauma, excessive physical efforts, or recent infection. He had no fever or cervical lymphadenopathy. All peripheral pulses were present, and there were no palpable masses or organ enlargement in the abdomen. Although a chest X-ray detected a well-defined round mass in the middle mediastinum adjacent to the aortic arch, a computed tomography angiogram (CTA) showed a thoracic aortic pseudoaneurysm located at the left subclavian artery ostium, measuring 4.2 cm 4.3 cm 4.3 cm in anteroposterior, longitudinal, and transverse diameter, respectively (Fig. 1). Other causes of chest pain were also ruled out. We opted for an urgent endovascular solution by means of stent grafting of the thoracic aorta combined with periscope stent grafting of the left subclavian artery. As we had no out-of-hours access to thoracic endografts in our hospital, we used a suitable-sized abdominal aortic extension cuff, with a 20% oversizing. This was a 36 mm 36 mm 49 mm aortic stent-graft extension (Endurant; Medtronic, MN). When introduced transfemorally, the 66-cm-long delivery catheter of the device is not long enough to reach and cover the left subclavian pseudoaneurysm, because this is intended to treat abdominal aortic and not thoracic aortic pathologies. To compensate this lack of length, a left retroperitoneal access was performed, and the delivery catheter was introduced via the left common iliac artery. The aortic cuff was deployed just distal to the origin of the left common carotid and covered the left subclavian artery ostium, whereas the patency of the left subclavian artery was maintained using the periscope technique, by using an 8 mm 100 mm
Annals of Vascular Surgery
Viabahn stent graft (Gore, Flagstaff, AZ), which was introduced via an open cutdown to the left axillary artery. Completion angiogram confirmed complete pseudoaneurysm exclusion without endoleak. Normal left upper limb pulses were palpable at the end of the procedure. Immediately after the operation, the patient developed bradypsychia, dysphasia, and disorientation. A minor stroke was suspected, and brain CTA confirmed an infarct in the left parietal region. The following day, chest thoracic CTA showed that there was complete thrombosis of the pseudoaneurysm and that both stent-grafts were patent without endoleak. The patient had an otherwise uneventful recovery and quickly improved from the stroke point of view. During his hospital stay, the patient was screened for infection and had several blood cultures taken. The initial blood cultures grew Staphylococcus schleiferi, a gram-positive coccus, but all subsequent blood cultures were negative. Labeled leukocyte scintigraphy with 99mTc showed no infectious process. Nevertheless, he was treated with intravenous vancomycin. He was well enough to be discharged home on the 10th postoperative day. At discharge, the patient had no dysphasia or any neurological deficits. He was able to feed himself and walk normally. He was prescribed oral antibiotics for one month and life-long antiplatelet and lipid-lowering therapy. He remains in good condition five years later, and CTAs show that both endografts are patent with no endoleak, and that the pseudoaneurysm has thrombosed and reduced in size compared with previous imaging (Fig. 2).
DISCUSSION Given that this case was managed by endovascular means, we do not have histological proof to confirm the diagnosis of a pseudoaneurysm. However, this is the most likely diagnosis given the sudden onset of the pain and the positive CTA findings. Furthermore, we believe this is a case of a spontaneous, atherosclerotic, noninfected pseudoaneurysm because, although we did find a gram-positive microorganism in the first blood culture, the patient had no fever or other symptoms and signs of infection. Hsu and Lin reported a series of 10 patients with an infected pseudoaneurysm at the level of the aortic arch branches. All but one had fever.6 Although Staphylococcus schleiferi, a subspecies of Staphylococcus, was isolated in blood culture, this has rarely been reported in human infections, and it is likely that the positive blood culture was, in fact, contamination from skin flora rather than true bacteremia and infection.12,13 Therefore, we believe this patient most likely suffered an acute pseudoaneurysm of the thoracic aorta secondary to an atherosclerotic penetrating aortic ulcer at the ostium of the left subclavian artery. This is backed by the fact that atherosclerotic plaques could be
Volume
-, -
2018
Case Report
1.e3
Fig. 1. Preoperative imaging. (A) A chest X-ray showing a well-defined round mass in the mediastinum, adjacent to the aortic arch in its cephalic portion. (B) CTA image and (C) 3D reconstruction showing a pseudoaneurysm
at the left subclavian artery ostium level. Please note the calcified atherosclerotic plaque in the aortic arch at the origin of the left subclavian artery. (D) Sizing and planning of the procedure.
Fig. 2. Postoperative and follow-up imaging. (A and B) CTA showing the final result of the endovascular repair 24 hours after the procedure. Please note the hump of the aortic endograft protruding into the
pseudoaneurysm. (C and D) A 5-year follow-up CTA showing a patent periscope graft and thrombosis of the pseudoaneurysm.
1.e4 Case Report
seen around the left subclavian origin and the aortic arch in the preoperative CTA of this patient. Reviewing the literature, we found only few other cases similar to the one described here.1e3 These lesions seem to be rarely reported isolated and usually present as being mycotic or traumatic in etiology or as part of a thoracic aortic aneurysm.1e6 Although a penetrating aortic ulcer is frequently observed in the descending aorta, this entity rarely affects only one aortic arch vessel. To date, a case of spontaneous rupture of an innominate artery caused by a penetrating ulcer has been reported in the English language literature;4 however, there are no published reports on acute, penetrating ulcer-related pseudoaneurysms located at the left subclavian artery ostium. Open surgery to treat such lesions is challenging and usually requires sternotomy or left thoracotomy with hypothermic cardiac arrest and cerebral protection. In addition, it carries a significant risk for mortality and serious complications. On the other hand, endovascular therapy, being minimally invasive, is appealing. Given that one or more of the aortic arch branches may have to be preserved, a fenestrated or a branched stent-graft option would be the ideal endovascular option here. However, this is usually custom-made and requires several weeks to prepare, which makes such an option not appropriate for emergency cases. Other endovascular options would include aortic stent grafting with a thoracic stent graft placed across the ostium of the left subclavian artery along with proximal occlusion of the artery to avoid retrograde perfusion of the aneurysm sac. This can be performed with open surgical ligation or with transcatheter embolization via a brachial approach using coils or plugs. Finally, although occlusion of left subclavian artery is usually well tolerated, revascularization may follow with a carotid-subclavian bypass.14 We opted for a totally endovascular option using two parallel stent grafts, one in the thoracic aorta and one in the left subclavian artery in periscope fashion. Although several formulas have been advocated for calculating aortic stent-graft oversizing when using parallel stent grafts, it is currently accepted that a 20e30% oversizing is appropriate to facilitate gutter formation and promote good wall apposition between the parallel grafts.15e17 Zone 3 thoracic aorta stent grafting, in particular, is a special area of thoracic aorta in which the results of parallel grafting are better because one is concerned only about the left subclavian artery patency and because the consequences of its occlusion are generally less serious.18
Annals of Vascular Surgery
Our case is unique in that we improvised and used an abdominal aortic stent-graft extension cuff instead of a dedicated thoracic endograft, the latter not being available in stock at the time. An Endurant aortic cuff of 36-mm diameter seemed suitable to exclude the pseudoaneurysm. However, the delivery catheter of the device, being designed for use in abdominal aortic pathologies, was not long enough to reach the target lesion transfemorally. As a result, to gain length, we accessed the left common iliac artery via a retroperitoneal approach. An alternative option would have been using the right subclavian artery as an access vessel for the delivery of the abdominal aortic cuff. We decided against this approach because of the theoretically higher likelihood of cerebral embolization and stroke and because of the free-flow orientation of the cuff. The choice of a periscope over a chimney approach for parallel stent grafting in the left subclavian artery was preferred as its downward direction is less likely to interfere with the ostium of the remaining aortic arch branches and compromise blood flow to these. The main drawback for the periscope configuration is the retrograde flow, increasing, theoretically, the risk of thrombosis. Moreover, periscope grafts might narrow the aortic lumen at the level of the distal aortic endograft landing zone and therefore can produce a flow limitation, which could be a problem in the abdominal aorta, but not in the thoracic aorta.10 Nevertheless, results from experienced units offering thoracic endografting combined with the chimneyperiscope techniques in the supraaortic branches are reassuring.8e10,19,20 A recent study documented satisfactory mid-term results showing an estimated 2-year survival, freedom from reintervention, freedom from endoleak, and freedom from branch occlusion of 75%, 77%, 86%, and 96%, respectively.20 Of course, further studies and long-term results are awaited. Using an abdominal aortic cuff to treat a thoracic aortic lesion may be considered as being somewhat controversial due to many potential technical limitations, such as an inadequate device or endograft length and/or an insufficient endograft diameter. Most of them could be overcome. Cuffs may be too short to obtain proper proximal and distal sealing, which means that a second such cuff will be needed. In this particular case, a 49-mm-long cuff was used to exclude a subclavian ostium of around 8e10 mm, so there was just a 19e20 mm proximal and distal sealing. This could be enough when the deployment is extremely precise in relatively straight (i.e., type I) aortic arches, such as the one
Volume
-, -
2018
in our patient, but most times, it could be insufficient, especially if parallel stent grafting is also used with high risk of type I endoleak. In this sense, the scenario described here represents a bailout procedure in the emergent or urgent settings when thoracic aorta diameters match with those of an abdominal aortic cuff. If a longer lesion is to be treated, an alternative option would be to use a longer abdominal cuff of the dimension 36 mm 70 mm. Finally, given that a minor stroke occurred in our patient, the take-home message from this case is that guide wire, catheter, and device manipulations in the aortic arch should be gentle and be kept to a minimum. Such procedures carry an inherent risk for stroke, particularly in the elderly and those with heavy atherosclerotic burden in the arch. Fortunately, in our case, this complication was transient with full recovery. In conclusion, this case demonstrates that it is feasible to treat difficult and complex aortic emergencies, such an acute pseudoaneurysm at the region of the left subclavian artery ostium, using a combination of thoracic endografting and parallel grafts in a periscope fashion. Endovascular therapy, in this emergency setting, seems to be an appealing lower risk alternative to complex open cardiothoracic surgery. The use of an abdominal aortic extension cuff, introduced through a retroperitoneal iliac access, could serve as a viable improvisation when suitable dedicated thoracic endografts are not available out of hours. The risk of intraoperative stroke should be minimized by gentle and careful endovascular maneuvers in the aortic arch. Finally, the durability of the chimney/periscope technique in the supraaortic branches is yet unknown, and further data are needed.
The authors thank Dr. Santiago Perez Cachafeiro and Andrea Valdes for contributing to the scientific development and production of the manuscript.
REFERENCES 1. Kawaguchi S, Watanabe M, Hachimaru T, et al. Atherosclerotic pseudoaneurysm of the left subclavian artery: a case report. Ann Thorac Cardiovasc Surg 2010;16:376e9. 2. Chen Y-F, Su C-S, Liu T-J, et al. Endovascular treatment of a nontraumatic left subclavian artery pseudoaneurysm. J Chin Med Assoc 2012;75:474e8. 3. Sanada J, Matsui O, Terayama N, et al. Stent-graft repair of a mycotic left subclavian artery pseudoaneurysm. J Endovasc Ther 2003;10:66e70.
Case Report
1.e5
4. Ito H, Yamamoto K, Hiraiwa T. Spontaneous innominate artery perforation presenting as hemoptysis. Gen Thorac Cardiovasc Surg 2007;55:73e5. 5. Cho KR, Stanson AW, Potter DD, et al. Penetrating atherosclerotic ulcer of the descending thoracic aorta and arch. J Thorac Cardiovasc Surg 2004;127:1393e9. 6. Hsu RB, Lin FY. Surgery for infected aneurysm of the aortic arch. J Thorac Cardiovasc Surg 2007;134:1157e62. 7. Ohrlander T, Sonesson B, Ivancev K, et al. The chimney graft: a technique for preserving or rescuing aortic branch vessels in stent-graft sealing zones. J Endovasc Ther 2008;15:427e32. 8. Gehringhoff B, Torsello G, Pitoulias GA, et al. Use of chimney grafts in aortic arch pathologies involving the supraaortic branches. J Endovasc Ther 2011;18:650e5. 9. Kolvenbach RR, Yoshida R, Pinter L, et al. Urgent endovascular treatment of thoraco-abdominal aneurysms using a sandwich technique and chimney grafts–a technical description. Eur J Vasc Endovasc Surg 2011;41: 54e60. 10. Pecoraro F, Pfammatter T, Mayer D, et al. Multiple periscope and chimney grafts to treat ruptured thoracoabdominal and pararenal aortic aneurysms. J Endovasc Ther 2011;18: 642e9. 11. Zehm S, Chemelli A, Jaschke W, et al. Long-term outcome after surgical and endovascular management of true and false subclavian artery aneurysms. Vascular 2014;22:161e6. 12. Leung MJ, Nuttall N, Pryce TM, et al. Colony variation in Staphylococcus lugdunensis. J Clin Microbiol 1998;36: 3096e8. 13. Fleurette J, Bes M, Brun Y, et al. Clinical isolates of Staphylococcus lugdunensis and S. schleiferi: bacteriological characteristics and susceptibility to antimicrobial agents. Res Microbiol 1989;140:107e18. 14. Peterson BG, Eskandari MK, Gleason TG, et al. Utility of left subclavian artery revascularization in association with endoluminal repair of acute and chronic thoracic aortic pathology. J Vasc Surg 2006;43:433e9. 15. Pecoraro F, Pfammatter T, Lachat M, et al. Overcoming Anatomic Limitations to EVAR with Chimney and Periscope Grafts. Technical tips and tricks for using chimney and/ or periscope grafts to successfully treat a wide range of complex aortic aneurysmal pathologies. Endovasc Today 2014;56e62. 16. Moulakakis KG, Papapetrou A, Giannakopoulos TG, et al. The chimney graft technique for preserving renal arteries in stent-graft sealing zones. Vasa 2012;41:295e300. 17. Shahverdyan R, Gawenda M, Brunkwall J. Triple-barrel graft as a novel strategy to preserve supra-aortic branches in arch-TEVAR procedures: clinical study and systematic review. Eur J Vasc Endovasc Surg 2013;45:28e35. 18. Zhu Y, Guo W, Liu X, et al. The single-centre experience of the supra-arch chimney technique in endovascular repair of type B aortic dissections. Eur J Vasc Endovasc Surg 2013;45: 633e8. 19. Wu ZY, Chen ZG, Ma L, et al. Outcomes of chimney and/or periscope techniques in the endovascular management of complex aortic pathologies. Chin Med J (engl) 2017;130: 2095e100. 20. Pecoraro F, Lachat M, Cayne NS, et al. Mid-term results of chimney and periscope grafts in supra-aortic branches in high risk patients. Eur J Vasc Endovasc Surg 2017;54: 295e302.
