|LETTER TO EDITOR
|Year : 2019 | Volume
| Issue : 3 | Page : 58-61
Checklists for left subclavian artery reconstruction in thoracic endovascular aortic repair
Xiaoyu Wu, Kaichuang Ye, Ruihua Wang, Jinbao Qin, Zhiyou Peng, Xinwu Lu
Department of Vascular Surgery, Shanghai Ninth People's Hospital Affiliated to Shanghai JiaoTong University, School of Medicine; Vascular Center of Shanghai JiaoTong University, Shanghai, China
|Date of Submission||03-Feb-2020|
|Date of Decision||29-Jul-2020|
|Date of Acceptance||01-Aug-2020|
|Date of Web Publication||25-Aug-2020|
Dr. Xinwu Lu
Department of Vascular Surgery, Shanghai Ninth People's Hospital Affiliated to Shanghai JiaoTong University, School of Medicine; Vascular Center of Shanghai JiaoTong University, 639 Zhizaoju Road, Shanghai 200011
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Wu X, Ye K, Wang R, Qin J, Peng Z, Lu X. Checklists for left subclavian artery reconstruction in thoracic endovascular aortic repair. Transl Surg 2019;4:58-61
|How to cite this URL:|
Wu X, Ye K, Wang R, Qin J, Peng Z, Lu X. Checklists for left subclavian artery reconstruction in thoracic endovascular aortic repair. Transl Surg [serial online] 2019 [cited 2021 Jun 20];4:58-61. Available from: http://www.translsurg.com/text.asp?2019/4/3/58/293426
| Background|| |
Stanford B thoracic aortic dissection (AD) or aneurysm is a life-threatening disorder requiring timely management. Over the recent years, thoracic endovascular aortic repair (TEVAR) has emerged as a treatment option for a multitude of aortic pathologies, including AD or aneurysm. However, coverage of the left subclavian artery (LSA) is required in up to over 40% of patients undergoing TEVAR due to limited proximal landing zone, which has been reported to be associated with an increased risk of neurological complications including stroke and spinal cord ischemia.,,, Reconstruction of the LSA during TEVAR due to the complex anatomic features and variation of the aortic arch is still a challenge. Recently, in situ laser fenestration is reported to be a feasible, effective, rapid, and safe option for the reconstruction of aortic arch branches during TEVAR.,, Here, we describe the checklist for LSA reconstruction in TEVAR of Stanford B thoracic AD with limited proximal landing zone and the trouble shootings that may occur.
| Preoperative Assessment and Preparation|| |
Preoperative general examination
Electrocardiogram, cardiopulmonary function, laboratory examination, and carotid artery ultrasound.
Preoperative imaging examination
Limited proximal landing zone is defined as a distance 1.5 cm from the LSA ostium to the proximal intimal tear; this is also defined as the proximal aortic healthy length between the LSA ostium and the proximal aortic hematoma 1.5 cm.
Perform aortic computed tomography angiography (CTA) examination to assess the parameters of the AD:
- The diameter of the aorta adjacent to the LSA;
- The extent of diseased lesion and whether the visceral arteries are involved;
- The diameter of the aorta in the proximal and distal estimated stent anchoring zone;
- The anatomical structure and diameter of the LSA;
- The location where the left vertebral artery originates;
- The anatomy, diameter, calcification, and stenosis of the bilateral iliac artery, left axillary artery, and left brachial artery (LBA).
Preoperative evaluation of the puncture approach and the expected difficulties during the operation
The bilateral common femoral arteries and LBA approaches require to be assessed.
Choice of anesthesia
General anesthesia is preferred, while local anesthesia can be also considered under close supervision.
Equipment and appliances required
810–1100 nm laser machine, 200–400 nm laser fiber; 55 cm COOK sheath (Flexor® Check-Flo® Introducer) or Terumo 45 cm Terumo 60 cm head shapeable sheath or directional adjustable sheath; pig tail marked catheter; 0.018” guidewire, Lunderquist guidewire or supercore guidewire; at least two Proglide suture devices; 6F and 8F or 10F puncture sheaths; 0.035” series 4 mm × 40 mm (400 nm laser fiber) and 0.018” series 4 mm × 40 mm (200 nm laser fiber); high-pressure balloon of with lower profiled tip; 0.035” series of 6 mm × 40 mm or 8 mm × 40 mm catheter balloon and high-pressure balloon with diameter comparable to that of LSA; 40 mm-long stent graft with diameter comparable to that of the LSA.
| Intraoperative Evaluation|| |
Appropriate position and exposure site of the patient
Supine position with left upper extremity being extended and bilateral groin area and left upper limb being exposed and sterilized.
Puncture the desired common femoral artery (CFA) for aortic stent transmission and preserve two Proglide suturing devices. LBA should be dissected and exposed (alternatively, the LBA can be percutaneously punctured, through which the branch covered stent is sent to the targeted site). Under the circumstances that Proglide suturing devices are not available, the CFA approach also requires to be dissected and exposed.
Monitoring of systemic heparinization and coagulation during surgery
Intraoperative administration of 60–80 U/kg of unfractionated heparin, which can be additionally administrated when the duration of the procedure exceeds 3 h. Intraoperative monitor of Activated Clotting Time of whole blood (ACT) every 30 min is desirable when possible and the ACT should be controlled at 200–300 s.
| Recommended Surgical Procedure|| |
Preserve two Proglide suturing devices after successful CFA puncture. Incise the LBA or LSA, depending on the diameter of the LBA. However, percutaneous puncture of LBA is also possible for stent graft being streaked to the target site.
Preserved catheter angiography
Place two pigtail-marked catheters into the ascending aorta from the CFA and LBA access, respectively. Performed angiography via pigtail catheter preserved in LBA to confirm the diagnosis of AD; to assess the location of the proximal rupture site, the extent of dissection, and the blood supplement to the visceral arteries; to verify whether the pigtail catheter from the CFA is located in the true lumen; and to determine the suitable C arm tube angle for the observation of aortic arch type (normally with the angle between 45° and 55° on the left side).
Exchange guidewire (e.g., Stiff guidewire) with Lunderquist guidewire. Transmit aortic stent delivery system to the aortic arch following the Lunderquist guidewire. Perform angiography through LBA approach and accurately locate where the left common carotid artery (LCCA) originates from the aortic arch. The proximal anchorage point of the thoracic aortic stent should be located on the distal side of the LCCA initiation site without covering the LCCA. Deploy the stent accurately under fluoroscopy.
Reconstruction of left subclavian artery by laser fenestration in thoracic endovascular aortic repair
- [Figure 1] after transmitting stiff guidewire following the LBA catheter, insert and transmit the 6F 55 cm-long COOK sheath or shapeable sheath to the outer membrane of the aortic stent, then withdraw the sheath core and guidewire. Adjust the direction of the sheath and contradict it tightly against the outer membrane of the covered stent and fix the position of the sheath stably (verified by rotating the C arm tube position and angiography)
- Test laser fiber energy in wet environmentin vitro and cut the fiber tip 0.5 mm off; after combining balloon catheter with the laser fiber, retract the balloon catheter to expose the distal 0.5 cm of a 400 nm laser fiber and secure the end of the balloon catheter to the laser fiber with a Y-valve. For fenestration, the relatively flexible 200 nm to 400 nm fiber laser fiber is recommended. 200 nm laser fiber is recommended for the combination with 0.18 balloon catheter, and laser fibers with other diameter are recommended for the combination with 0.35 balloon catheter
- Place the fiber and balloon catheter into the 55 cm-long COOK sheath (or shapeable sheath) and transmit them forward until resistance or obstruction occurs. Observe the distance between the “MARK” of the balloon catheter and the aortic stent under fluoroscopy, which should be about 1.0–1.5 cm. Rotate the C-arm tube from different angles, and confirm whether the sheath tip and the laser fiber are in contact with the stent graft (it can be verified if the sheath tip causes slight morphological change of the stent, after pushing the sheath forward)
- Parameters of laser machine suggested for fenestration: 18W output energy with pulsed mode.
|Figure 1: In situ laser fenestration of left subclavian artery during thoracic endovascular aortic repair. (a) Aortic angiography in left anterior oblique view. (b) 4 mm × 40 mm balloon catheter was retracted to expose the distal 0.5 cm of an 810 nm laser fiber, which were fixed together and gently advanced in the sheath directly to touch the fabric of the stent graft as perpendicular as possible during laser triggering. Red arrows indicated positions of the tips of the balloon catheter and the laser fiber, respectively; (c) balloon dilation was performed to enlarge the fenestration of left subclavian artery; (d) deployment of the left subclavian artery stent|
Click here to view
Trigger the laser for 2–3 times and push the balloon catheter forward. If the forward push goes smoothly, withdraw the laser fiber and exchange the hard guidewire and perform balloon expansion (Successful fenestration can be verified by the following three means: (1) by balloon catheter angiography; (2) whether there is obvious notch during performing balloon expansion; and (3) in cases that the first two methods are ineffective, exchange the balloon with pigtail catheter and then withdraw guidewire, it could discriminate whether the fenestration succeed according to the morphological change of the pigtail catheter tip by rotating the pigtail catheter. If the laser and the balloon catheter combination reflects a clear sense of breakthrough once the laser is triggered, and/or the laser fiber and balloon catheter combination could be pushed forward for only short distance after 3–4 times of laser triggering, exchange the laser fiber and 0.35 balloon with 0.18 guidewire and 0.18 balloon, and then perform initial balloon catheter expansion. Success of fenestration can be verified as described above
It should be noted that this balloon catheter for initial expansion should be high-pressure balloon with lower profiled tip.
- Withdraw the initial preexpanded balloon catheter and exchange it with the second preexpanded balloon (high-pressure) for further expansion. The diameter should be slightly smaller than the diameter of LSA
Mark the position where the notch occurs and records the pressure at which notch disappears during balloon expansion. Withdraw the preexpanded balloon catheter, select catheter sheath suitable for the LSA covered stent, and deploy the covered stent with the diameter matching the diameter of LSA.
After the branch stent graft reaches the predetermined position, slowly release the stent and stop release procedure while the head of the stent is completely released. Withdraw the main sheath of branch stent until there is obvious resistance. Next, observe the notch mark of the balloon expansion on the screen, and confirm that the branch stent does not exceed 5 mm in the main aortic stent, and then slowly release the branch stent and select the matching balloon to perform postexpansion until the stent is fully deployed. If the notch is not completely disappeared with the balloon being expanded more than 15 atmospheric pressure (atm), a balloon-expanded bare stent with the corresponding diameter can be deployed in the branch-covered stent.
- Ending of surgery. Following the LSA guidewire, pigtail catheter should be sent to the ascending aorta and perform aortic angiography to assess the isolation of the AD and the patency of the LSA. Withdraw the CFA sheath and suture the puncture site by preserved Proglide suturing devices. Suture the LBA incision or compress the LBA puncture point, end the surgery.
| Trouble Shootings and Countermeasures|| |
Femoral artery is severely calcificated, slender etc.
Through posterior peritoneal incision, the external iliac artery or the common iliac artery can be dissected as aortic stent approach.
Iliac artery is distorted, severe calcificated, occluded, etc.
Distorted lesion can be twisted and straightened by super-hard guidewire, severe stenosis, occlusion or calcification, can be pretreated with endovascular stenting.
The subclavian artery is distorted, slender, occluded, etc.
Alternatives: LBA incision, inferior subclavian artery incision, vascularization of the occluded LSA.
Fenestration failure more often occurs in cases of unfriendly LSA anatomy (which originates at an acute angle from the aortic arch or from the sidewall of the aortic arch), Type III aortic arch, or in cases that the LSA is involved in AD and the guidewire could not be preserved in the true lumen of LSA, etc.
When catheter sheath is difficult to be contradict to the aortic covered stent, try the following methods:
- Select the elbow sheath and the tip-shapeable catheter sheath. In order to observe the position of the catheter sheath and the outer membrane of the aortic stent, adjust the catheter sheath direction and the C-arm tube angle, and push-retract the catheter sheath slightly. When the catheter sheath has reached the membrane of the aortic stent graft, the catheter sheath can be fixed to complete the subsequent fenestration procedure
- Transmit the elbow GAIDING into the sheath of the catheter, then adjust the direction of the GAIDING and the C-arm tube, apply the combination of the elbow support catheter and the laser fiber, and/or adjust the direction of the support catheter to make sure that the laser fiber is contradict to the covered aortic stent
- Applying the fenestration sheath. When the head of fenestration sheath reaches the initiation site of LSA, fully expand the balloon of the fenestration sheath. Insert the laser fiber and balloon catheter combination into the sheath and push it forward until there is obvious resistance and then perform the fenestration procedure. It is recommended to select 200–400 nm laser fiber with good flexibility.
Laser liber passes through the aortic stent, but the balloon catheter fails to follow
When there is obvious sense of breakthrough after the laser being triggered, the balloon catheter however cannot enter the aortic stent and a clear resistance occurs after push the laser for 5 mm to 1 cm, try to exchange the laser fiber with 0.018” guidewire and balloon to the ascending aorta to perform balloon expansion. Exchange the 0.018” system of guidewire and balloon with that of 0.035” system to perform the subsequent fenestration.
| Immediate Evaluation After Fenestration|| |
Insufficient expansion of the left subclavian artery stent
If the residual stenosis after stent implantation is >30%, balloon postexpansion is normally needed. High-pressure balloons, such as Mustang and Dolado balloons, are required to postexpand the stent at 14–20 atm. If the notch is not completely disappeared with the balloon being expanded more than 15 atm, a balloon-expanded bare stent with the corresponding diameter should be deployed in the branch-covered stent.
Type I endoleak
In this case, it is necessary to extend the aortic stent toward the ascending aorta/proximal end and reconstruct the carotid artery or even the innominate artery with laser-assisted fenestration if necessary.
The left subclavian artery stent migration or shortening
Preserved guidewire in the LSA after postoperative angiography and deploy a second covered stent.
Stent thrombosis within 30 days after surgery is often considered technical failure or due to insufficient postoperative anticoagulation. In addition to the avoidance of the above-mentioned technical factors, postoperative anticoagulation for short time, and postdischarge antiplatelet and anticoagulation should prevent stent thrombosis formation. For patients who have already developed stent thrombosis, percutaneous catheter directed thrombolysis or mechanical thrombectomy is the treatment of choice.
| Postoperative Treatment and Follow-Up|| |
Patents should receive dual-antiplatelet therapy (e.g., clopidogrel and aspirin) for 3 month and subsequent single-antiplatelet therapy for at least 1 year.
Patients should be followed-up at 1, 3, 6, and 12 months postoperatively. Perform aortic CTA examination annually to assess the isolation of AD and the patency of the LSA stent.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Bossone E, LaBounty TM, Eagle KA. Acute aortic syndromes: Diagnosis and management, an update. Eur Heart J
Feezor RJ, Martin TD, Hess PJ, Klodell CT, Beaver TM, Huber TS, Seeger JM, Lee WA. Risk factors for perioperative stroke during thoracic endovascular aortic repairs (TEVAR). J Endovasc Ther
Matsumura JS, Lee WA, Mitchell RS, Farber MA, Murad MH, Lumsden AB, Greenberg RK, Safi HJ, Fairman RM; Society for Vascular Surgery. The Society for Vascular Surgery Practice Guidelines: Management of the left subclavian artery with thoracic endovascular aortic repair. J Vasc Surg
Cooper DG, Walsh SR, Sadat U, Noorani A, Hayes PD, Boyle JR. Neurological complications after left subclavian artery coverage during thoracic endovascular aortic repair: A systematic review and meta-analysis. J Vasc Surg
Rizvi AZ, Murad MH, Fairman RM, Erwin PJ, Montori M. 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
Zhao Z, Qin J, Yin M, Liu G, Liu X, Ye K, Wang R, Shi H, Li W, Jiang M, Lu X. In situ
laser stent graft fenestration of the left subclavian artery during thoracic endovascular repair of Type B aortic dissection with limited proximal landing zones: 5-year outcomes. J Vasc Interv Radiol 2020;31:1321-7.
Qin J, Zhao Z, Liu G, Ye K, Yin M, Cui C, Shi H, Peng Z, Jiang M, Liu X, Li W, Lu X. In situ
diode laser fenestration of aortic arch stent grafts during thoracic endovascular aortic repair of Stanford type a aortic dissection. EuroIntervention
Yan D, Shi H, Qin J, Zhao Z, Yin M, Liu X, Ye K, Liu G, Li W, Lu X. Outcomes of emergency in situ
laser fenestration-assisted thoracic endovascular aortic repair in patients with acute Stanford type A aortic dissection unfit for open surgery. J Vasc Surg