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Interventional Case Record
Interventional Case Record
Thoracic endovascular aortic repair (TEVAR) with preoperative bypass
Thoracic endovascular aortic repair (TEVAR) with preoperative bypass
Contributed by : Armaandeep Singh Aulakh
Contributed by : Armaandeep Singh Aulakh
Introduction:
Introduction:
Aortic aneurysms are a significant cardiovascular pathology, characterized by abnormal dilation and weakening of the aortic wall, which increases the risk of rupture. Traditional open surgical repair has been the gold standard for treatment, but thoracic endovascular aortic repair (TEVAR) has emerged as a less invasive alternative. We describe a successful TEVAR procedure performed on a 67-year-old man with an aortic aneurysm involving the arch of the aorta.
Aortic aneurysms are a significant cardiovascular pathology, characterized by abnormal dilation and weakening of the aortic wall, which increases the risk of rupture. Traditional open surgical repair has been the gold standard for treatment, but thoracic endovascular aortic repair (TEVAR) has emerged as a less invasive alternative. We describe a successful TEVAR procedure performed on a 67-year-old man with an aortic aneurysm involving the arch of the aorta.
Case presentation:
Case presentation:
A 67 year old man presented with the history of intermittent retrosternal chest pain since one year. The patient was a known hypertensive on regular medications. Clinical examination of his respiratory and cardiovascular system was normal. Chest radiographs showed a large, vertically oval, soft tissue opacity in the upper zone of left lung. The lateral margin of the opacity was well defined and extending superior to the clavicle suggesting that the opacity was in the posterior mediastinum (Fig 1).
A 67 year old man presented with the history of intermittent retrosternal chest pain since one year. The patient was a known hypertensive on regular medications. Clinical examination of his respiratory and cardiovascular system was normal. Chest radiographs showed a large, vertically oval, soft tissue opacity in the upper zone of left lung. The lateral margin of the opacity was well defined and extending superior to the clavicle suggesting that the opacity was in the posterior mediastinum (Fig 1).
Fig 1: Frontal chest radiograph showing a posterior mediastinal mass obliterating the aortic knuckle
The opacity merged with the aortic knuckle. A CT aortogram showed focal aneurysmal dilation of the aorta just distal to the origin of left subclavian artery, for a length of 54 mm with a maximum diameter 81 mm with an eccentric mural thrombus (Fig 2 , 3).
The opacity merged with the aortic knuckle. A CT aortogram showed focal aneurysmal dilation of the aorta just distal to the origin of left subclavian artery, for a length of 54 mm with a maximum diameter 81 mm with an eccentric mural thrombus (Fig 2 , 3).
Figs 2 and 3 : Axial and sagittal (MIP images) of CT Aortogram show a partially thrombosed saccular aneurysm of the proximal descending aorta.
The MIP image of CT Aortogram is shown in Figure 4.
The MIP image of CT Aortogram is shown in Figure 4.
Fig 4 : MIP image of the CT Aortogram– shows a saccular aneurysm just distal to the left SCA.
Stent Graft Deployment:
Stent Graft Deployment:
Right common femoral artery arteriotomy was performed. A 5F sheath was placed in the right CFA, through which a Lunderquist wire was positioned in the aortic arch using 5F headhunter catheter.
Right common femoral artery arteriotomy was performed. A 5F sheath was placed in the right CFA, through which a Lunderquist wire was positioned in the aortic arch using 5F headhunter catheter.
Figure 5 shows the angiographic image with the measurement guide wire..
Figure 5 shows the angiographic image with the measurement guide wire..
Fig 5 (right) : Arch Aortogram shows partially thrombosed aneurysm of the distal aortic arch and proximal descending thoracic aorta with patent right CCA- left CCA- left SCA bypass.Marker pigtail catheter for measurements and Lunderquist wire for stent graft deployment are seen in the aortic arch.
Based on preoperative measurements and aortic morphology, 38 X160 stent graft (Ankura TAA, Lifetech) was selected and advanced over the Lunderquist wire. The covered segment of stent graft was deployed across the left common carotid artery and left subclavian artery (Fig 6).
Based on preoperative measurements and aortic morphology, 38 X160 stent graft (Ankura TAA, Lifetech) was selected and advanced over the Lunderquist wire. The covered segment of stent graft was deployed across the left common carotid artery and left subclavian artery (Fig 6).
Fig 6 : Fluoroscopy image shows Deployment of the aortic stent graft
Completion Angiography: Post-stent graft deployment, completion angiography was performed to confirm proper graft position, assess endoleaks, and verify exclusion of the aneurysm. It showed adequate placement of the stent graft. However, there was antegrade filling of the proximal left CCA. The distal left CCA and left SCA were filling via the bypass (Fig 7). The aneurysmal sac had been excluded from the circulation.
Completion Angiography: Post-stent graft deployment, completion angiography was performed to confirm proper graft position, assess endoleaks, and verify exclusion of the aneurysm. It showed adequate placement of the stent graft. However, there was antegrade filling of the proximal left CCA. The distal left CCA and left SCA were filling via the bypass (Fig 7). The aneurysmal sac had been excluded from the circulation.
Fig 7 : Arch Aortogram shows antegrade flow in the left CCA. Left SCA origin is occluded by the graft. The 8 marker is the point from where the covered portion of the stent graft begins
The antegrade flow in the left CCA was of concern for two reasons,
The antegrade flow in the left CCA was of concern for two reasons,
a. It might have caused endoleak.
a. It might have caused endoleak.
b. Due to antegrade flow in the left CCA, there was a risk of thrombosis of the right CCA- left CCA bypass.
b. Due to antegrade flow in the left CCA, there was a risk of thrombosis of the right CCA- left CCA bypass.
Hence, it was decided to occlude the proximal left CCA.
Hence, it was decided to occlude the proximal left CCA.
6. Left brachial artery access was secured using a 5F short sheath. A 4F Berenstein catheter – microcatheter combination was advanced into the left CCA via by the pass.A 10mm X40 cm and a 14mm X40 cm pushable coils were used to occlude the proximal left CCA ( Fig 8).
6. Left brachial artery access was secured using a 5F short sheath. A 4F Berenstein catheter – microcatheter combination was advanced into the left CCA via by the pass.A 10mm X40 cm and a 14mm X40 cm pushable coils were used to occlude the proximal left CCA ( Fig 8).
Fig 8 : Fluoroscopy image show- Through left brachial artery access- a 4F Berenstein catheter and Progreat 2.7 microcatheter combination was advanced into the left CCA via bypass. A 10mm X40 cm and a 14mm X40 cm pushable coils were used to occlude the proximal left CCA
Final arch aortogram demonstrated adequate placement of the aortic stent graft with no antegrade flow in the proximal left CCA. Distal left CCA and left SCA were filling via bypass (Fig 9).
Final arch aortogram demonstrated adequate placement of the aortic stent graft with no antegrade flow in the proximal left CCA. Distal left CCA and left SCA were filling via bypass (Fig 9).
Fig 9- DSA Aortogram shows coil mass in the left proximal CCA with cessation of antegrade flow at the left CCA origin. The left CCA is filling via bypass.
The procedure was uneventful. Post procedure, course in ward was uneventful. A CT aortogram was performed prior to discharge which showed exclusion of the aneurysm with thrombosis of the excluded portion. (Fig 10)
The procedure was uneventful. Post procedure, course in ward was uneventful. A CT aortogram was performed prior to discharge which showed exclusion of the aneurysm with thrombosis of the excluded portion. (Fig 10)
Fig 10: Axial section of Post procedure CT Aortogram at the same level as Fig 2 shows thrombosis of the saccular aneurysm.
Fig 11 : There was good flow in bilateral internal carotid arteries and vertebral arteries.
Discussion:
Discussion:
TEVAR continues to rapidly evolve and is being applied to a growing number of aortic pathologies. Given the perioperative, short- and mid-term morbidity and mortality rates, TEVAR is quickly surpassing traditional open surgical intervention as the ideal procedure for patients undergoing intervention of the descending thoracic aorta and applicability to ascending and arch pathologies is being explored.
TEVAR continues to rapidly evolve and is being applied to a growing number of aortic pathologies. Given the perioperative, short- and mid-term morbidity and mortality rates, TEVAR is quickly surpassing traditional open surgical intervention as the ideal procedure for patients undergoing intervention of the descending thoracic aorta and applicability to ascending and arch pathologies is being explored.
Indications for TEVAR-
Indications for TEVAR-
1. Aortic Aneurysm- Current guidelines recommend endovascular intervention for asymptomatic, degenerative, or traumatic aneurysms exceeding 5.5 cm as well as all saccular aneurysms.(3)
1. Aortic Aneurysm- Current guidelines recommend endovascular intervention for asymptomatic, degenerative, or traumatic aneurysms exceeding 5.5 cm as well as all saccular aneurysms.(3)
2. PAU & IMH- (Penetrating aortic ulcer and intramural hematoma)- Asymptomatic PAU without IMH can be managed medically with close radiographic follow-up; however, if IMH is present, the patient is symptomatic, or radiographic growth is documented, then urgent operative intervention is indicated(1). PAUs with depth greater than 10 mm or diameter wider than 20 mm are at a higher risk of progression and should be considered for repair.(5)
2. PAU & IMH- (Penetrating aortic ulcer and intramural hematoma)- Asymptomatic PAU without IMH can be managed medically with close radiographic follow-up; however, if IMH is present, the patient is symptomatic, or radiographic growth is documented, then urgent operative intervention is indicated(1). PAUs with depth greater than 10 mm or diameter wider than 20 mm are at a higher risk of progression and should be considered for repair.(5)
1. Aortic pseudoaneurysm (traumatic)- For aortic pseudoaneurysms that are clinically symptomatic, greater than 2 cm in size, increasing in size via radiographic studies or actively ruptured/leaking.
1. Aortic pseudoaneurysm (traumatic)- For aortic pseudoaneurysms that are clinically symptomatic, greater than 2 cm in size, increasing in size via radiographic studies or actively ruptured/leaking.
2. Stanford Type B Aortic dissection- Uncomplicated/ complicated acute or chronic aortic dissection. Medical management alone may lead to progression of the AD in patients (INSTEAD XL trial suggest a longterm benefit to TEVAR, with significant decreases in aortaspecific mortality and disease progression when compared with medical management alone).(4)
2. Stanford Type B Aortic dissection- Uncomplicated/ complicated acute or chronic aortic dissection. Medical management alone may lead to progression of the AD in patients (INSTEAD XL trial suggest a longterm benefit to TEVAR, with significant decreases in aortaspecific mortality and disease progression when compared with medical management alone).(4)
The proximal thoracic aorta is divided into various zones ( Fig 12 a,b)
The proximal thoracic aorta is divided into various zones ( Fig 12 a,b)
Fig. 12 a
Fig. 12 b
LANDING ZONE- is the segment of normal aorta proximal and distal to the aneurysm. Adequate landing zone is needed for precise placement and approximation of the aortic stent graft.
LANDING ZONE- is the segment of normal aorta proximal and distal to the aneurysm. Adequate landing zone is needed for precise placement and approximation of the aortic stent graft.
The application of traditional TEVAR requires a proximal and distal landing zone of at least 2 cm; however, patients with thoracic aortic pathology can present with a disease that extends into the aortic arch, which leaves them without a suitable proximal landing zone distal to the left subclavian artery (LSA). Whenever a stent graft is planned to be placed in zones 0, 1, or 2 of the arch, a careful evaluation and plan are needed for revascularization of the arch vessels (Figure 11).
The application of traditional TEVAR requires a proximal and distal landing zone of at least 2 cm; however, patients with thoracic aortic pathology can present with a disease that extends into the aortic arch, which leaves them without a suitable proximal landing zone distal to the left subclavian artery (LSA). Whenever a stent graft is planned to be placed in zones 0, 1, or 2 of the arch, a careful evaluation and plan are needed for revascularization of the arch vessels (Figure 11).
In an emergent setting, the LSA can be covered without revascularization. However, in patients who have undergone coronary artery bypass grafting with a left internal mammary artery (LIMA) graft, LSA revascularization is mandatory. Other indications include absent/atretic contralateral vertebral artery, dominant left vertebral artery, presence of a functional left arm arteriovenous fistula.
In an emergent setting, the LSA can be covered without revascularization. However, in patients who have undergone coronary artery bypass grafting with a left internal mammary artery (LIMA) graft, LSA revascularization is mandatory. Other indications include absent/atretic contralateral vertebral artery, dominant left vertebral artery, presence of a functional left arm arteriovenous fistula.
Zone 2 sealing without left subclavian artery (LSA) revascularization can result in upper extremity ischemia, SCI, and vertebrobasilar insufficiency. The EUROSTAR registry, reported a significantly higher incidence of spinal cord ischemia or stroke (8.4%) in patients without LSA revascularization compared to patients with revascularization (2).
Zone 2 sealing without left subclavian artery (LSA) revascularization can result in upper extremity ischemia, SCI, and vertebrobasilar insufficiency. The EUROSTAR registry, reported a significantly higher incidence of spinal cord ischemia or stroke (8.4%) in patients without LSA revascularization compared to patients with revascularization (2).
Extranatomical bypass prior to TEVAR-
Extranatomical bypass prior to TEVAR-
- Extranatomical bypass can be performed via neck dissection which extended the landing zone in cases where the aortic pathology involves the origin of great vessels. (Fig 13,14)
- Extranatomical bypass can be performed via neck dissection which extended the landing zone in cases where the aortic pathology involves the origin of great vessels. (Fig 13,14)
Fig 13. Left CCA- SCA bypass graft.
fig 14 : Transposition of left SCA to left CCA.
Fig. 12, 13, 14 are reproduced from: "Expanding the Landing Zone for TEVA By Daniel K. Han, MD, RPVI; Christine Jokisch, BS; and James F. McKinsey, MD" https://evtoday.com/articles/2016-nov/expanding-the-landing-zone-for-tevar
Main teaching points in this case are-
Main teaching points in this case are-
• Importance of adequate landing zones and importance of extranatomic bypass in TEVAR
• Importance of adequate landing zones and importance of extranatomic bypass in TEVAR
• Endoleaks and their prevention.
• Endoleaks and their prevention.
ENDOLEAKS-
ENDOLEAKS-
Endoleak is defined as the persistent perigraft blood flow within the aneurysm sac.
Endoleak is defined as the persistent perigraft blood flow within the aneurysm sac.
Type I- due to poor apposition at proximal or distal landing zones.
Type I- due to poor apposition at proximal or distal landing zones.
Type II- Due to retrograde flow into the aneurysm sac via branch vessels eg. intercostal arteries, IMA, lumbar arteries etc.
Type II- Due to retrograde flow into the aneurysm sac via branch vessels eg. intercostal arteries, IMA, lumbar arteries etc.
Type III- due to poor overlap between two grafts
Type III- due to poor overlap between two grafts
Type IV- due to porosity within the graft material
Type IV- due to porosity within the graft material
Type V- Endotension- expansion of the aneurysm sac when no leak is identified.
Type V- Endotension- expansion of the aneurysm sac when no leak is identified.
Type I and III require urgent management as son as they are identified (during the procedure itself).
Type I and III require urgent management as son as they are identified (during the procedure itself).
Type II can be followed up and treated electively.
Type II can be followed up and treated electively.
In our case, after deployment of the stent graft there was partial coverage of the left CCA origin, leading to antegrade flow within the left CCA. This might have caused endoleak and also increase the risk of thrombosis of carotid carotid bypass due to competitive antegrade flow in the left CCA.
In our case, after deployment of the stent graft there was partial coverage of the left CCA origin, leading to antegrade flow within the left CCA. This might have caused endoleak and also increase the risk of thrombosis of carotid carotid bypass due to competitive antegrade flow in the left CCA.
Hence, the proximal left CCA was occluded using multiple pushable coils to stop antegrade flow.
Hence, the proximal left CCA was occluded using multiple pushable coils to stop antegrade flow.
References:
References:
1. Martin Grabenwöger and others, Thoracic Endovascular Aortic Repair (TEVAR) for the treatment of aortic diseases: a position statement from the European Association for Cardio-Thoracic Surgery (EACTS) and the European Society of Cardiology (ESC), in collaboration with the European Association of Percutaneous Cardiovascular Interventions (EAPCI), European Heart Journal, Volume 33, Issue 13, July 2012, Pages 1558–1563, https://doi.org/10.1093/eurheartj/ehs074
1. Martin Grabenwöger and others, Thoracic Endovascular Aortic Repair (TEVAR) for the treatment of aortic diseases: a position statement from the European Association for Cardio-Thoracic Surgery (EACTS) and the European Society of Cardiology (ESC), in collaboration with the European Association of Percutaneous Cardiovascular Interventions (EAPCI), European Heart Journal, Volume 33, Issue 13, July 2012, Pages 1558–1563, https://doi.org/10.1093/eurheartj/ehs074
2. Buth J, Harris PL, Hobo R, et al. Neurologic complications associated with endovascular repair of thoracic aortic pathology: incidence and risk factors. a study from the European Collaborators on Stent/Graft Techniques for Aortic Aneurysm Repair (EUROSTAR) registry. J Vasc Surg. 2007;46:1103-1110.
2. Buth J, Harris PL, Hobo R, et al. Neurologic complications associated with endovascular repair of thoracic aortic pathology: incidence and risk factors. a study from the European Collaborators on Stent/Graft Techniques for Aortic Aneurysm Repair (EUROSTAR) registry. J Vasc Surg. 2007;46:1103-1110.
3. Manetta F, Newman J, Mattia A. Indications for Thoracic EndoVascular Aortic Repair (TEVAR): A Brief Review. Int J Angiol. 2018 Dec;27(4):177-184. doi: 10.1055/s-0038-1666972. Epub 2018 Aug 2. PMID: 30410287; PMCID: PMC6221793.
3. Manetta F, Newman J, Mattia A. Indications for Thoracic EndoVascular Aortic Repair (TEVAR): A Brief Review. Int J Angiol. 2018 Dec;27(4):177-184. doi: 10.1055/s-0038-1666972. Epub 2018 Aug 2. PMID: 30410287; PMCID: PMC6221793.
4. Nienaber CA, Kische S, Rousseau H, et al; INSTEAD-XL trial. Endovascular repair of type B aortic dissection: long-term results of the randomized investigation of stent grafts in aortic dissection trial. Circ Cardiovasc Interv 2013;6(4):407–416
4. Nienaber CA, Kische S, Rousseau H, et al; INSTEAD-XL trial. Endovascular repair of type B aortic dissection: long-term results of the randomized investigation of stent grafts in aortic dissection trial. Circ Cardiovasc Interv 2013;6(4):407–416
5. Nation DA, Wang GJ. TEVAR: Endovascular Repair of the Thoracic Aorta. Semin Intervent Radiol. 2015 Sep;32(3):265-71. doi: 10.1055/s-0035-1558824. PMID: 26327745; PMCID: PMC4540616.
5. Nation DA, Wang GJ. TEVAR: Endovascular Repair of the Thoracic Aorta. Semin Intervent Radiol. 2015 Sep;32(3):265-71. doi: 10.1055/s-0035-1558824. PMID: 26327745; PMCID: PMC4540616.