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Novel temporary endovascular shunt technique to assist in situ fenestration for endovascular reconstruction of the distal aortic arch
Novel temporary endovascular shunt technique to assist in situ fenestration for endovascular reconstruction of the distal aortic arch Jiang Xiong, MD, Wei Guo, MD, Xiaoping Liu, MD, Xin Jia, MD, Xiaohui Ma, MD, and Lijun Wang, MD, Beijing, China Thoracic endovascular aortic repair (TEVAR) of arch pathology presents special challenges for revascularization. To obtain an anatomic reconstruction of the arch arteries, in situ fenestration with extra-anatomic bypass has been increasingly used in TEVAR. We report a case involving TEVAR for a pseudoaneurysm at zone 2 of the thoracic aorta in a 37-year-old man with the use of in situ fenestration assisted by a temporary endovascular shunt technique. (J Vasc Surg 2014;-:1-4.)
Distal aortic arch aneurysm exclusion by thoracic endovascular aortic repair (TEVAR) for the revascularization of the arch arteries still has considerable technical challenges. In situ fenestration (ISF) has been reported to be a useful technique to revascularize arch arteries.1,2 However, it is difficult to maintain adequate blood flow to arch arteries without an extra-anatomic bypass for the time required to perform the ISF.3 This report describes a successful TEVAR approach to repair a large pseudoaneurysm situated in zone 2 of the thoracic aorta with the use of ISF and a temporary endovascular shunt (TES) to maintain blood flow to the brain. CASE REPORT A 37-year-old man who was known to have Bechet disease presented with hoarseness of the voice for 15 days. He also complained of an intermittent dull pain in the left side of the chest for 8 years. Computed tomographic angiography of the aorta showed a pseudoaneurysm of 6-cm diameter at zone 2 (Fig 1). Because the patient refused open surgery and because hybrid repair with carotid-carotid and carotid-subclavian bypass had a high risk of anastomotic pseudoaneurysm in the longterm follow-up, it was proposed to exclude the pseudoaneurysm by means of TEVAR because revascularization with the use of ISF had previously been used successfully in our department. Adequate cerebral perfusion could be obtained with the use of a TES. ISF and specifically TES for this procedure were
From the Department of Vascular Surgery, Vascular Center of Military, Chinese PLA General Hospital, Beijing, China. Author conflict of interest: none. Reprint requests: Wei Guo, MD, Department of Vascular Surgery, Clinical Division of Surgery, Chinese PLA General Hospital, No. 28, Fuxing Road, Beijing, China PR, 100853 (e-mail: [email protected]). The editors and reviewers of this article have no relevant financial relationships to disclose per the JVS policy that requires reviewers to decline review of any manuscript for which they may have a conflict of interest. 0741-5214/$36.00 Copyright Ó 2014 by the Society for Vascular Surgery. http://dx.doi.org/10.1016/j.jvs.2013.12.030
approved by the institutional review board of our hospital, and written informed consent was obtained from this patient. Under general anesthesia, an aorto-cranial angiogram revealed patency of the anterior communicating artery and confirmed the absence of a dominant vertebral artery. To obtain an adequate proximal landing zone, the proximal end of the stent graft (SG) was planned to be deployed in zone 1 of the thoracic arch. The left common carotid artery (LCCA) and left subclavian artery (LSA) would then be revascularized with the use of ISF and a TES to maintain cerebral blood flow. Unfractionated heparin was administered by means of intravenous bolus injection at a dose of 100 IU/kg. A percutaneous puncture of the distal LCCA was made and a Perclose ProGlide (Abbott Vascular, Redwood City, Calif) was deployed, as has been previously described.4 A Raabe 7F 45-cm sheath (Cook Inc, Bloomington, Ind) was then inserted over a 0.035-inch guide wire through the LCCA, and the tip was advanced to the proximal end of the LCCA. Next, two 9F 85-cm sheaths (Starway Medical Technology, Inc, Beijing, China) with an oval side port (2 10 mm and 30 cm to the tip) made during the procedure were used to establish a TES (Fig 2, A). This commercial sheath was normally used for delivering the atrial septal defect occluder device. One was inserted percutaneously through the left brachial artery with the side port located in the LSA close to the orifice of the left vertebral artery and the tip in the descending aorta. A Perclose ProGlide was first deployed in the left common femoral artery (CFA) through a retrograde percutaneous puncture and the other sheath was inserted over a 0.035-inch guide wire through the left CFA so that the tip of the sheath was located in the LCCA 10 cm from its origin, with the side port in the descending aorta (Fig 2, B). The intra-operative angiogram of the TES is shown in Fig 2, C. Over a Lunderquist guide wire through a right CFA cutdown, a 32 160-mm Zenith TX2 SG (Cook Inc) was delivered retrogradely and deployed with the proximal end situated immediately behind the origin of the innominate artery in the aortic arch. The systemic arterial blood pressure was then regulated until the systolic blood pressure (SBP) in the sheath of the LCCA was maintained at approximately 120 mm Hg, with an arterial wave form similar to that in the aorta.
1
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2 Xiong et al
Fig 1. Computed tomographic angiography before thoracic endovascular aortic repair (TEVAR) shows the eccentric pseudoaneurysm of zone 2. After that, the fenestration of the SG through the LCCA and LSA was performed by ISF technique. A 2.75 15-mm cutting balloon (Flextome; Boston Scientific, Natick, Mass) was used to dilate across the graft material. A balloon-expandable covered stent, 28 mm in length (Jostent; Abbott, Vascular Instruments, Rangendingen, Germany), was inflated across each fenestration and dilated to a diameter of 10 mm. Afterward, the introducer was inserted into the sheath of the TES and the sheaths were withdrawn. Completion angiography showed complete exclusion of the pseudoaneurysm without any endoleak and normal flow to the LCCA and LSA (Fig 2, D). The left brachial artery puncture site was compressed to obtain hemostasis. Other puncture sites were closed by Perclose ProGlide devices and routine surgical closure. A computed tomographic angiography scan at 6 months showed that the pseudoaneurysm remained excluded, with normal flow to the CCA and LSA (Fig 2, E).
DISCUSSION The main problem with endovascular repair of a distal aortic arch disease is the revascularization of arch arteries. Coverage of the innominate or LCCA is not physiologically tolerable, and coverage of the LSA without revascularization is discouraged because it can be complicated by both stroke and spinal cord ischemia.5,6 ISF is an alternative technique to this problem. Previously, carotid-carotideleft subclavian bypasses were necessary before ISF to maintain the blood flow to the arch arteries during the procedure.7,8 However, extra-anatomical bypass operations have risks of neck hematoma stroke and long-term anastomotic
complications in a patient with Bechet disease.9 Because of this, the patient refused open surgery. Therefore, a total endovascular method to repair the pseudoaneurysm was developed. To establish a useful TES, the following requirements were necessary. There had to be adequate blood flow into the LCCA through the shunt conduit during ISF. The 9F sheaths were used as the shunt conduit because the inner diameter of the 9F sheaths is larger than that of the carotid shunt (Edwards Lifesciences, LLC, Irvine, Calif), which is used for carotid endarterectomy. Compared with other sheaths, it is easier to modify the side port of the Starway sheath. The area of the oval side port was larger than that of the sheath itself. This enabled adequate flow in the shunt conduit without limiting flow in the side port. After SG deployment, the blood flow to the LCCA was assessed by means of monitoring the SBP and the arterial pressure wave form in the sheaths of the LCCA. It was found that after the SG had covered the orifice of the LCCA, the SBP in the LCCA was only 10 mm Hg lower than that in the aorta, and the wave form was similar to that in the aorta. This indicated sufficient antegrade blood flow to the LCCA from the TES. In addition, the transcranial Doppler and duplex ultrasound examinations could provide objective evidence of the direction and volume of the blood flow in LCCA during the procedure. These techniques will be investigated for measuring the blood inflow in future cases. To maintain adequacy of blood flow in the TES after SG placement, the sheath had to have a high radial force to prevent collapse against compression by the SG. There was concern that the handmade side port may affect the mechanical structure of the sheath, so that it could be difficult to recover. Therefore, on the one hand, the oval side port was made with the major radius parallel to the longitudinal axis of the sheath because this has less influence on the mechanical structure of the sheath. On the other hand, after successful ISF, the sheaths were withdrawn with their introducers in place to prevent sheath fracture at the site of the side port. Finally, after deployment of the SG, if the blood flow from TES was inadequate, a bail-out chimney procedure for the LCCA was prepared in advance by having a sheath and a guide wire in place at the time of SG deployment. This chimney technique could have been completed in several minutes and hence could have limited effect on the blood flow to the LCCA.10 CONCLUSIONS TES is a new technique to maintain sufficient antegrade blood flow to the arch arteries during an ISF procedure. Although clinical success was achieved in this case, the safety and effectiveness of TES and ISF need further investigation. We appreciate Dr Alan Bray, Division of Vascular and Endovascular Surgery, Lake Macquarie Hospital, Newcastle, Australia, for giving valuable advice.
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Fig 2. Intraoperative and follow-up fluoroscopic image at thoracic endovascular aortic repair (TEVAR) shows (A) temporary endovascular shunt (TES) was performed with the use of 9F 85 cm sheaths with a home-made oval side port (2 10 mm and 30 cm to the tip). B, Schematic diagram of TES. The pseudoaneurysm (PA) of zone 2 was excluded by stent graft (SG). The descending aortaeleft subclavian artery (LSA) TES (right hollow arrow) and the descending aortaeleft common carotid artery (LCCA) TES (left hollow arrow) were established by use of two 9F long sheaths with oval side ports (black arrow). Red arrows of the red solid line indicate the direction of blood flow in the TES. C, Sheaths for TES (hollow arrow) were placed, and delivery system containing a SG was advanced to zone 1. D, Completion angiography shows a well-sealed pseudoaneurysm free from endoleaks and anatomical reconstruction of LCCA and LSA. E, Six-month follow-up computed tomographic angiography shows complete exclusion of the pseudoaneurysm and no endoleaks, with patent LCCA and LSA.
AUTHOR CONTRIBUTIONS Conception and design: WG Analysis and interpretation: JX, WG, XL Data collection: JX, XL, XJ, XM, LW Writing the article: JX Critical revision of the article: JX Final approval of the article: WG Statistical analysis: Not applicable Obtained funding: Not applicable Overall responsibility: WG
2.
3.
4.
5.
REFERENCES 1. McWilliams RG, Fearn SJ, Harris PL, Hartley D, Semmens JB, Lawrence-Brown MM. Retrograde fenestration of endoluminal grafts from
6.
target vessels: feasibility, technique, and potential usage. J Endovasc Ther 2003;10:946-52. McWilliams RG, Murphy M, Hartley D, Lawrence-Brown MM, Harris PL. In situ stent-graft fenestration to preserve the left subclavian artery. J Endovasc Ther 2004;11:170-4. Murphy EH, Stanley GA, Ilves M, Knowles M, Dimaio JM, Jessen ME, et al. Thoracic endovascular repair (TEVAR) in the management of aortic arch pathology. Ann Vasc Surg 2012;26:55-66. Lee WA, Brown MP, Nelson PR, Huber TS. Total percutaneous access for endovascular aortic aneurysm repair (“Preclose” technique). J Vasc Surg 2007;45:1095-101. Rizvi AZ, Murad MH, Fairman RM, Erwin PJ, Montori VM. The effect of left subclavian artery coverage on morbidity and mortality in patients undergoing endovascular thoracic aortic interventions: a systematic review and meta-analysis. J Vasc Surg 2009;50:1159-69. Matsumura JS, Lee WA, Mitchell RS, Farber MA, Murad MH, Lumsden AB, et al. The society for vascular surgery practice guidelines:
4 Xiong et al
management of the left subclavian artery with thoracic endovascular aortic repair. J Vasc Surg 2009;50:1155-8. 7. Palchik E, Bakken AM, Wolford HY, Saad WE, Davies MG. Subclavian artery revascularization: an outcome analysis based on mode of therapy and presenting symptoms. Ann Vasc Surg 2008;22:70-8. 8. Byrne J, Darling RC 3rd, Roddy SP, Mehta M, Paty PS, Kreienberg PB, et al. Long term outcome for extra-anatomic arch reconstruction: an analysis of 143 procedures. Eur J Vasc Endovasc Surg 2007;34:444-50.
JOURNAL OF VASCULAR SURGERY --- 2014
9. Lotfi S, Clough RE, Ali T, Salter R, Young CP, Bell R, et al. Hybrid repair of complex thoracic aortic arch pathology: long-term outcomes of extra-anatomic bypass grafting of the supra-aortic trunk. Cardiovasc Intervent Radiol 2013;36:46-55. 10. Hiramoto JS, Schneider DB, Reilly LM, Chuter TA. A double-barrel stent-graft for endovascular repair of the aortic arch. J Endovasc Ther 2006;13:72-6. Submitted May 16, 2013; accepted Dec 14, 2013.
Distal aortic arch aneurysm exclusion by thoracic endovascular aortic repair (TEVAR) for the revascularization of the arch arteries still has considerable technical challenges. In situ fenestration (ISF) has been reported to be a useful technique to revascularize arch arteries.1,2 However, it is difficult to maintain adequate blood flow to arch arteries without an extra-anatomic bypass for the time required to perform the ISF.3 This report describes a successful TEVAR approach to repair a large pseudoaneurysm situated in zone 2 of the thoracic aorta with the use of ISF and a temporary endovascular shunt (TES) to maintain blood flow to the brain. CASE REPORT A 37-year-old man who was known to have Bechet disease presented with hoarseness of the voice for 15 days. He also complained of an intermittent dull pain in the left side of the chest for 8 years. Computed tomographic angiography of the aorta showed a pseudoaneurysm of 6-cm diameter at zone 2 (Fig 1). Because the patient refused open surgery and because hybrid repair with carotid-carotid and carotid-subclavian bypass had a high risk of anastomotic pseudoaneurysm in the longterm follow-up, it was proposed to exclude the pseudoaneurysm by means of TEVAR because revascularization with the use of ISF had previously been used successfully in our department. Adequate cerebral perfusion could be obtained with the use of a TES. ISF and specifically TES for this procedure were
From the Department of Vascular Surgery, Vascular Center of Military, Chinese PLA General Hospital, Beijing, China. Author conflict of interest: none. Reprint requests: Wei Guo, MD, Department of Vascular Surgery, Clinical Division of Surgery, Chinese PLA General Hospital, No. 28, Fuxing Road, Beijing, China PR, 100853 (e-mail: [email protected]). The editors and reviewers of this article have no relevant financial relationships to disclose per the JVS policy that requires reviewers to decline review of any manuscript for which they may have a conflict of interest. 0741-5214/$36.00 Copyright Ó 2014 by the Society for Vascular Surgery. http://dx.doi.org/10.1016/j.jvs.2013.12.030
approved by the institutional review board of our hospital, and written informed consent was obtained from this patient. Under general anesthesia, an aorto-cranial angiogram revealed patency of the anterior communicating artery and confirmed the absence of a dominant vertebral artery. To obtain an adequate proximal landing zone, the proximal end of the stent graft (SG) was planned to be deployed in zone 1 of the thoracic arch. The left common carotid artery (LCCA) and left subclavian artery (LSA) would then be revascularized with the use of ISF and a TES to maintain cerebral blood flow. Unfractionated heparin was administered by means of intravenous bolus injection at a dose of 100 IU/kg. A percutaneous puncture of the distal LCCA was made and a Perclose ProGlide (Abbott Vascular, Redwood City, Calif) was deployed, as has been previously described.4 A Raabe 7F 45-cm sheath (Cook Inc, Bloomington, Ind) was then inserted over a 0.035-inch guide wire through the LCCA, and the tip was advanced to the proximal end of the LCCA. Next, two 9F 85-cm sheaths (Starway Medical Technology, Inc, Beijing, China) with an oval side port (2 10 mm and 30 cm to the tip) made during the procedure were used to establish a TES (Fig 2, A). This commercial sheath was normally used for delivering the atrial septal defect occluder device. One was inserted percutaneously through the left brachial artery with the side port located in the LSA close to the orifice of the left vertebral artery and the tip in the descending aorta. A Perclose ProGlide was first deployed in the left common femoral artery (CFA) through a retrograde percutaneous puncture and the other sheath was inserted over a 0.035-inch guide wire through the left CFA so that the tip of the sheath was located in the LCCA 10 cm from its origin, with the side port in the descending aorta (Fig 2, B). The intra-operative angiogram of the TES is shown in Fig 2, C. Over a Lunderquist guide wire through a right CFA cutdown, a 32 160-mm Zenith TX2 SG (Cook Inc) was delivered retrogradely and deployed with the proximal end situated immediately behind the origin of the innominate artery in the aortic arch. The systemic arterial blood pressure was then regulated until the systolic blood pressure (SBP) in the sheath of the LCCA was maintained at approximately 120 mm Hg, with an arterial wave form similar to that in the aorta.
1
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2 Xiong et al
Fig 1. Computed tomographic angiography before thoracic endovascular aortic repair (TEVAR) shows the eccentric pseudoaneurysm of zone 2. After that, the fenestration of the SG through the LCCA and LSA was performed by ISF technique. A 2.75 15-mm cutting balloon (Flextome; Boston Scientific, Natick, Mass) was used to dilate across the graft material. A balloon-expandable covered stent, 28 mm in length (Jostent; Abbott, Vascular Instruments, Rangendingen, Germany), was inflated across each fenestration and dilated to a diameter of 10 mm. Afterward, the introducer was inserted into the sheath of the TES and the sheaths were withdrawn. Completion angiography showed complete exclusion of the pseudoaneurysm without any endoleak and normal flow to the LCCA and LSA (Fig 2, D). The left brachial artery puncture site was compressed to obtain hemostasis. Other puncture sites were closed by Perclose ProGlide devices and routine surgical closure. A computed tomographic angiography scan at 6 months showed that the pseudoaneurysm remained excluded, with normal flow to the CCA and LSA (Fig 2, E).
DISCUSSION The main problem with endovascular repair of a distal aortic arch disease is the revascularization of arch arteries. Coverage of the innominate or LCCA is not physiologically tolerable, and coverage of the LSA without revascularization is discouraged because it can be complicated by both stroke and spinal cord ischemia.5,6 ISF is an alternative technique to this problem. Previously, carotid-carotideleft subclavian bypasses were necessary before ISF to maintain the blood flow to the arch arteries during the procedure.7,8 However, extra-anatomical bypass operations have risks of neck hematoma stroke and long-term anastomotic
complications in a patient with Bechet disease.9 Because of this, the patient refused open surgery. Therefore, a total endovascular method to repair the pseudoaneurysm was developed. To establish a useful TES, the following requirements were necessary. There had to be adequate blood flow into the LCCA through the shunt conduit during ISF. The 9F sheaths were used as the shunt conduit because the inner diameter of the 9F sheaths is larger than that of the carotid shunt (Edwards Lifesciences, LLC, Irvine, Calif), which is used for carotid endarterectomy. Compared with other sheaths, it is easier to modify the side port of the Starway sheath. The area of the oval side port was larger than that of the sheath itself. This enabled adequate flow in the shunt conduit without limiting flow in the side port. After SG deployment, the blood flow to the LCCA was assessed by means of monitoring the SBP and the arterial pressure wave form in the sheaths of the LCCA. It was found that after the SG had covered the orifice of the LCCA, the SBP in the LCCA was only 10 mm Hg lower than that in the aorta, and the wave form was similar to that in the aorta. This indicated sufficient antegrade blood flow to the LCCA from the TES. In addition, the transcranial Doppler and duplex ultrasound examinations could provide objective evidence of the direction and volume of the blood flow in LCCA during the procedure. These techniques will be investigated for measuring the blood inflow in future cases. To maintain adequacy of blood flow in the TES after SG placement, the sheath had to have a high radial force to prevent collapse against compression by the SG. There was concern that the handmade side port may affect the mechanical structure of the sheath, so that it could be difficult to recover. Therefore, on the one hand, the oval side port was made with the major radius parallel to the longitudinal axis of the sheath because this has less influence on the mechanical structure of the sheath. On the other hand, after successful ISF, the sheaths were withdrawn with their introducers in place to prevent sheath fracture at the site of the side port. Finally, after deployment of the SG, if the blood flow from TES was inadequate, a bail-out chimney procedure for the LCCA was prepared in advance by having a sheath and a guide wire in place at the time of SG deployment. This chimney technique could have been completed in several minutes and hence could have limited effect on the blood flow to the LCCA.10 CONCLUSIONS TES is a new technique to maintain sufficient antegrade blood flow to the arch arteries during an ISF procedure. Although clinical success was achieved in this case, the safety and effectiveness of TES and ISF need further investigation. We appreciate Dr Alan Bray, Division of Vascular and Endovascular Surgery, Lake Macquarie Hospital, Newcastle, Australia, for giving valuable advice.
JOURNAL OF VASCULAR SURGERY Volume -, Number -
Xiong et al 3
Fig 2. Intraoperative and follow-up fluoroscopic image at thoracic endovascular aortic repair (TEVAR) shows (A) temporary endovascular shunt (TES) was performed with the use of 9F 85 cm sheaths with a home-made oval side port (2 10 mm and 30 cm to the tip). B, Schematic diagram of TES. The pseudoaneurysm (PA) of zone 2 was excluded by stent graft (SG). The descending aortaeleft subclavian artery (LSA) TES (right hollow arrow) and the descending aortaeleft common carotid artery (LCCA) TES (left hollow arrow) were established by use of two 9F long sheaths with oval side ports (black arrow). Red arrows of the red solid line indicate the direction of blood flow in the TES. C, Sheaths for TES (hollow arrow) were placed, and delivery system containing a SG was advanced to zone 1. D, Completion angiography shows a well-sealed pseudoaneurysm free from endoleaks and anatomical reconstruction of LCCA and LSA. E, Six-month follow-up computed tomographic angiography shows complete exclusion of the pseudoaneurysm and no endoleaks, with patent LCCA and LSA.
AUTHOR CONTRIBUTIONS Conception and design: WG Analysis and interpretation: JX, WG, XL Data collection: JX, XL, XJ, XM, LW Writing the article: JX Critical revision of the article: JX Final approval of the article: WG Statistical analysis: Not applicable Obtained funding: Not applicable Overall responsibility: WG
2.
3.
4.
5.
REFERENCES 1. McWilliams RG, Fearn SJ, Harris PL, Hartley D, Semmens JB, Lawrence-Brown MM. Retrograde fenestration of endoluminal grafts from
6.
target vessels: feasibility, technique, and potential usage. J Endovasc Ther 2003;10:946-52. McWilliams RG, Murphy M, Hartley D, Lawrence-Brown MM, Harris PL. In situ stent-graft fenestration to preserve the left subclavian artery. J Endovasc Ther 2004;11:170-4. Murphy EH, Stanley GA, Ilves M, Knowles M, Dimaio JM, Jessen ME, et al. Thoracic endovascular repair (TEVAR) in the management of aortic arch pathology. Ann Vasc Surg 2012;26:55-66. Lee WA, Brown MP, Nelson PR, Huber TS. Total percutaneous access for endovascular aortic aneurysm repair (“Preclose” technique). J Vasc Surg 2007;45:1095-101. Rizvi AZ, Murad MH, Fairman RM, Erwin PJ, Montori VM. The effect of left subclavian artery coverage on morbidity and mortality in patients undergoing endovascular thoracic aortic interventions: a systematic review and meta-analysis. J Vasc Surg 2009;50:1159-69. Matsumura JS, Lee WA, Mitchell RS, Farber MA, Murad MH, Lumsden AB, et al. The society for vascular surgery practice guidelines:
4 Xiong et al
management of the left subclavian artery with thoracic endovascular aortic repair. J Vasc Surg 2009;50:1155-8. 7. Palchik E, Bakken AM, Wolford HY, Saad WE, Davies MG. Subclavian artery revascularization: an outcome analysis based on mode of therapy and presenting symptoms. Ann Vasc Surg 2008;22:70-8. 8. Byrne J, Darling RC 3rd, Roddy SP, Mehta M, Paty PS, Kreienberg PB, et al. Long term outcome for extra-anatomic arch reconstruction: an analysis of 143 procedures. Eur J Vasc Endovasc Surg 2007;34:444-50.
JOURNAL OF VASCULAR SURGERY --- 2014
9. Lotfi S, Clough RE, Ali T, Salter R, Young CP, Bell R, et al. Hybrid repair of complex thoracic aortic arch pathology: long-term outcomes of extra-anatomic bypass grafting of the supra-aortic trunk. Cardiovasc Intervent Radiol 2013;36:46-55. 10. Hiramoto JS, Schneider DB, Reilly LM, Chuter TA. A double-barrel stent-graft for endovascular repair of the aortic arch. J Endovasc Ther 2006;13:72-6. Submitted May 16, 2013; accepted Dec 14, 2013.