Use of fenestrated stent grafts in treatment of acute aortic syndrome
Objective. To study the possibility and determine the safety of using stent grafts with on table and in situ fenestration in patients with acute aortic syndrome.
Patients and methods. From 2019 to 2021, specialists of the Republican Cardiological Center (Ufa) retrospectively analyzed the results of endovascular treatment of 34 patients with acute aortic syndrome.
Results and discussion. All 34 patients were operated on within the first 48 hours after the disease was detected. They were subjected to various types of endovascular debranching. In 26 patients, zone 2 according to Ishimaru was selected with on table or in situ TEVAR (Thoracic Endovascular Aortic Repair) of the left subclavian artery; in 6 cases, double fenestration of the left common carotid and left subclavian arteries were performed during implantation into zone 1 according to Ishimaru. In 2 cases, total endovascular debranching was performed during implantation into zone 0 according to Ishimaru. The average operation time was 137.35±61.4 minutes, the average contrast consumption was 295.2±79.2 ml, and the average volume of blood loss was 78±121.1 ml. In all cases, the technical success was 100%, however, during the control MSCT, 2 cases of type 3 endoleaks were identified, which were further embolized. One patient developed retrograde dissection of the ascending aorta and the aortic arch 2 months after surgery. Further surgical correction was performed. Overall in-hospital mortality was 0%, and only 3 (8.8%) patients died in the remote period.
Conclusion. Thoracic endovascular aortic repair (TEVAR) of the aortic arch with various types of endovascular debranching can be considered as an alternative and effective method for treatment of patients with acute aortic syndrome.
Ключевые слова:TEVAR; acute aortic syndrome; endovascular debranching; fenestrated stent grafts, aortic arch
Funding. The study had no financial support.
Conflict of interest. The authors declare no conflicts of interest.
Authors’ contribution. Study conception and design - Khafizov T.N., Kataev V.V.; preoperative preparation, follow-up of patients - Abkhalikova E.E.; operative interventions - Khafizov T.N., Idrisov I.A., Imaev T.E., Kataev V.V.; selection of consumables - Khafizov T.N., Nikolaeva I.E.; statistical processing - Yamanaeva I.E.; draft manuscript preparation - Khafizov T.N., Kataev V.V.; manuscript revision - Nikolaeva I.E.
For citation: Khafizov T.N., Idrisov I.A., Kataev V.V., Nikolaeva I.E., Imaev T.E., Abkhalikova E.E., Yamanaeva I.E. Use of fenestrated stent grafts in treatment of acute aortic syndrome. Angiology and Vascular Surgery. Journal named Academician A.V. Pokrovsky. 2022; 28 (3): 56-67. DOI: https://doi.org/10.33029/1027-6661-2022-28-3-56-67 (in Russian)
Aortic diseases greatly contribute to a wide spectrum of cardiovascular system pathology. To them belong various-localization aortic aneurysms, acute aortic syndrome, atherosclerotic and inflammatory lesions, genetic diseases (e.g., Marfan syndrome) . Thoracic endovascular aortic repair (TEVAR) is currently considered to be a leading method of treating patients with aneurysms and dissection of the descending aorta, even with the pathological process involving the distal portion of the aortic arch [2, 3]. In patients with diseases of the aortic arch and descending portion, it is important to preserve blood flow in aortic branches, decreasing the risk of intraoperative and early postoperative complications . Taking into consideration the development of new and improvement of currently existing endovascular techniques, more and more patients are subjected to minimally invasive treatment, however, one of the limiting anatomical factors is involvement of the aortic arch branches into pathological process. Until recently, all patients whose anatomy permits of performing endoprosthetic repair of the arch and descending portion of the aorta were first subjected to open operative intervention - rerouting of 1 or 2 aortic arches, to be then followed by aortic endoprosthetic repair. This methodology envisages a stagewise manner in treatment of pathology of the aortic arch and descending portion, thus however increasing the risk of intra- and postoperative complications and not always possible to perform in emergency situation
Objective. To study the possibility and determine the safety of using stent grafts with on table and in situ fenestration in patients with acute aortic syndrome.
Patients and methods
To assess efficiency and safety of using stent grafts with different types of fenestration, we carried out a retrospective analysis of treatment of 34 patients with acute aortic syndrome, operated on at the Republican Cardiological Centre (Ufa) from 2019 to 2021. All patients were preoperatively subjected to emergency multislice computed tomography (MSCT) in order to decide upon the method of operative treatment. A consilium of physicians, consisting of endovascular and cardiovascular surgeons, cardiologists and resuscitators evaluated the general condition, followed by laboratory and instrumental studies to decide upon therapeutic policy. Operative interventions in all patients were performed within the first 48 hours - endoprosthetic repair of the thoracic artery with various types of debranching. The question on the site of proximal fixation of the stent graft was decided according to the Ishimaru classification (Fig. 1).
The necessity of performing fenestrations in all operations was the absence of an optimal zone of fixation for the stent graft’s proximal portion, with the length of the unaltered neck averagely amounting to 8±4.6 cm. To determine the possibility and type of fenestration we analyzed and measured the distance between the ostia of brachiocephalic arteries, ostial diameter, angles of ostial origin from the aortic arch, using the CT findings. The analysis and calculations were made using software for image processing in the format DICOM - OsiriX MD (Fig. 2)
All patients received implantation of the stent graft Ankura (LifeTech) into the aortic cavity. With the aim of endovascular debranching, we used in situ or on table fenestration followed by implantation of balloon-expandable graft systems Bentley BeGraft CP Stent or balloon-expandable stents Restorer (iVascular).
The choice of an aortic stent graft was substantiated by the fact the that the manufacturer had already taken into consideration the possibility of performing fenestrations and at the expense of factory-imbedded radiopaque markers it is possible to position the fenestrated portion under roentgenoscopy relative to the brachiocephalic artery ostia. On the proximal covered part of the stent graft there is a marker in the form of the figure 8, and on the lower margin is a marker in the form of the letter O. Also all along the length of the upper edge there is a stiffening rib provided with radiopaque markers at a certain distance. Making a decision of on table fenestration after determining the size of fenestration in the program OsiriX MD in order to facilitate fenestration orientation on the circumference of the stent graft it is possible to present it as a watch face and to determine the position of the target vessel’s ostium (Fig. 3). This is followed by retrieval of the stent graft from the delivery system for several centimeters depending on the fenestration size. According to the watch face presented we determined the level and angle of fenestration formation. The orifice was formed using an electrocoagulator, with the task herein being to form even and clear edges in order to prevent embolization of endograft tissue. Formation of fenestration was followed by placing the endograft into the delivery system. Then, after performing on table fenestration and assembly of the stent graft to the delivery system under roentgen control at the expense of the contrast markers 8 and O, the fenestrated portion was neatly positioned under the ostium of the target vessel. After complete expansion of the stent graft, we performed control angiography in order to specify correctness and success of placement.
Having analyzed encountered complications, we concluded that if the proximal portion of aortic dissection was in the area of the ostia of brachiocephalic arteries (Fig. 4) in order to decrease the risk of type 3 endoleak it was necessary to perform in situ fenestration, thus ensuring greater sealing in such clinical situations.
The study included a total of 34 patients: 8 (24%) women and 26 (76%) men, with an average age of 58.2±15.9 years and average body mass index of 28.3±5.5.
22 (65%) patients were diagnosed with coronary artery disease. The mean level of creatinine clearance amounted to 68.4±20.9 ml/min/1.73 m2. Revealing stage III and higher chronic kidney disease in order to prevent renal damage and to decrease contrast media consumption, the operative intervention was performed supported by the Vessel Navigator (Philips).
The highest volume of blood loss amounted to 950 ml in a female patient with left-sided hemothorax, hemopericardium and hemomediastinum. The average intraoperative blood loss amounted to 78.0±121.1 ml. Surgical isolation of the common femoral artery through the lateral access was used as an approach in all patients, with no complications. The technical success was 100%. The control MSCT revealed type 3 endoleaks in 2 patients. Successful endovascular embolization was performed. In 1 patient embolization of the endoleak was carried out using microcoils (Cook). In the second patient in addition to coils a glue composition was used: through the femoral approach the false lumen was catheterized, through a microcatheter the endoleak was embolized with the glue component Squid. The control angiography demonstrated cessation of blood flow by 90%. For adequate cessation of blood flow it was decided in addition to the glue composition to use microcoils (Cook).
In 1 case, we observed retrograde aortic dissection having developed 2 months after endoprosthetic repair. The patient was subjected to surgical correction.
The perioperative mortality rate was 0%. In the remote period 3 (8.8%) patients died: of them, 2 from COVID-19 and 1 a year later from unknown causes.
Table 1 shows operation characteristics of the patients. In implantation of stent grafts we chose zone 2 to according to Ishimaru in 26 patients. Of these, on table fenestration without endoprosthetic repair of branches in 11 patients, on table fenestration followed by graft implantation to the left subclavian artery (LSCA) in 8 patients, and in situ fenestration with graft implantation to the LSCA in 7 patients.
Ishimaru zone 1 was chosen in 6 patients. Of these, 4 patients were subjected to on table fenestration followed by implantation of grafts or stent system Restorer into the LSCA and left common carotid artery (LCCA), and 2 patients underwent on table fenestration without prosthetic repair of the aortic arch branches, since an optimal angiographic result was obtained.
Two patients with the involvement of all aortic branches in dissection were subjected to total endovascular debranching - the endograft placed proximal to the origin of the brachiocephalic trunk (BCT) not less than by 2 cm, followed by repair of the aortic arch branches. Both patients underwent on table fenestration followed by endoprosthetic repair of all branches with the use of endografts in the BCT - LifeStream (Bard), BeGraft in the LCCA and LSCA. Table 2 shows the types and characteristics of debranching. As an example, we present the following clinical case report.
Clinical case report
A 70-year-old woman felt retrosternal pain radiating to the left portion of the chest. Emergency MSCT angiography (Fig. 5) revealed a dissecting aneurysm of the thoracic portion of the aorta, with rupture, hemodiastinum, bilateral hemothorax. She was found to have pronounced comorbid background, including hypertension, type 2 insulin dependent diabetes mellitus, class II obesity, lower limb varicose veins, and hypothyroidism, thus determining refusal of open operative intervention. The woman was emergently referred to the SBHI “Republican Cardiological Center”. Anesthesia was induced by intubation narcosis. Through a femoral approach inserted was a superstiff guidewire and placed in the ascending portion of the aorta. Aortography determined the level of stent graft placement. on table fenestration 1 cm in diameter was performed under the left SCA. Along the superstiff guidewire to the level of the beginning of the BCT with the originating LSCA inserted was a Lifetech stent graft 30 mm in diameter and 180 cm long. Control aortography was performed, demonstrating stent graft expansion. On aortography, the ostia of the LCCA and LSCA were not compromised (Fig. 6). Aortic MSCT to control endoleaks was performed 1 month later (Fig. 7).
Currently, there remain many unsolved problems in aortic surgery for acute aortic syndrome. Thus, foreign authors have reported that in aortic arch dissection, the use of the most common frozen elephant trunk technique in acute period is accompanied by high risk of mortality and postoperative complications, which is also applicable to Russian realities [5-7]. Endovascular surgery also has certain limitations in treatment of patients with aortic arch pathology. More often, these are anatomical limitations which may be solved at the expense of debranching. Various types of debranching were performed in our patients, depending on the situation.
Generally, types of debranching may be divided into 2 large groups: open and endovascular. Open debranching envisages as the first stage carotid-subclavian shunting or another variant of debranching followed by aortic arch repair. Complications of these operations more often include retrograde dissection due to mismatched diameters of the endoprosthesis and native aorta, as well as the development of type 1 endoleak at the expense of aortic wall degeneration . Some Russian authors have reported very good results of using hybrid techniques in treatment of aortic arch pathology with high rates of successful installation of the endoprosthesis and low rates of complications and mortality [9, 10]. However, a hybrid approach is not always feasible in acute aortic syndrome.
Endovascular methods in patients with acute aortic syndrome can be divided into 3 groups: on table and in situ fenestrations, and the parallel grafting technique. According to the literature data, the use of the parallel grafting technique is recommended as a saving technique due to an increased risk of repeat interventions and the development of type 1A endoleaks in the remote period. It was confirmed in analyzing treatment of 373 patients, with the incidence of type 1A endoleaks amounting to 9.4% and that of reinterventions to 10.6% .
The on table technique envisages extraction of the stent graft from the delivery system outside the patient and removal of a portion of PTFE surface with the help of an electrocoagulator for positioning of the ostia of aortic arch branches (Fig. 8). The in situ technique consists in formation of a fenestration in an endograft directly through the target vessel (Fig. 9)
For example, if debranching of the LSCA is necessary, puncture of the radial or brachial artery is performed, inserting an introducer and required tools to form fenestration in the stent graft from the SCA ostium. As a special tool, we used a needle for fenestration manufactured by the LifeTech Company. Also, it is possible to use an electrocoagulator, laser. Then, this orifice is enlarged with the help of a balloon and endograft is inserted into the LSCA.
The performed analysis of endovascular treatment of 34 patients with acute aortic syndrome demonstrated efficacy and safety of the applied technology in treatment of this cohort of severely ill patients.
Endovascular prosthetic repair of the aortic arch with various types of debranching (on table, in situ) may be regarded as an alternative, effective and safe method for treatment of patients with acute aortic syndrome, for whom open operation is impossible for various reasons.
1. 2014 ESC Guidelines on the diagnosis and treatment of aortic diseases. Russian Journal of Cardiology. 2015; 7 (123): 7-72. DOI: https://doi.org/10.15829/1560-4071-2015-07-7-72 (in Russian)
2. Manetta F., Newman J., Mattia A. Indications for Thoracic EndoVascular Aortic Repair (TEVAR): A Brief Review. International Angiology. 2018; 27 (4): 177-184. DOI: https://doi.org/10.1055/s-0038-1666972
3. Rinaldi E., Kahlberg A., Carta N., et al. Late Open Conversion Following Failure of EVAR and TEVAR: “State of the Art”. CardioVascular and Interventional Radiology. 2020; 43 (12): 1855-1864. DOI: https://doi.org/10.1007/s00270-020-02636-w
4. Editor’s Choice e Current Options and Recommendations for the Treatment of Thoracic Aortic Pathologies Involving the Aortic Arch: An Expert Consensus Document of the European Association for Cardio-Thoracic Surgery (EACTS) & the European Society for Vascular Surgery (ESVS). European Journal of Vascular and Endovascular Surgery. 2019; 57 (2): 165e198. DOI: https://doi.org/10.1016/j.ejvs.2018.09.016
5. Ahmad W., Mylonas S., Majd P., Brunkwall J.S. A current systematic evaluation and meta-analysis of chimney graft technology in aortic arch diseases. Journal of Vascular Surgery. 2017; 66 (5): 1602-1610.e2. DOI: https://doi.org/10.1016/j.jvs.2017.06.100
6. Shadanov A.A., Sirota D.A., Lyashenko M.M., Chernyavskiy A.M. Early and mid-term outcomes of thoracic aortic reconstruction using the frozen elephant trunk technique: a single-center retrospective study. Patologiya Krovoobrashcheniya i Kardiokhirurgiya. 2021; 25 (3): 61-70. DOI: https://doi.org/10.21688/1681-3472-2021-3-61-70 (in Russian)
7. Hanif H., Dubois L., Ouzounian M., et al. Canadian Thoracic Aortic Collaborative (CTAC) Investigators. Aortic Arch Reconstructive Surgery With Conventional Techniques vs Frozen Elephant Trunk: A Systematic Review and Meta-Analysis. Canadian Journal of Cardiology. 2018; 34 (3): 262-273. DOI: https://doi.org/10.1016/j.cjca.2017.12.020
8. Faulds J., Sandhu H.K., Estrera A.L., Safi H.J. Minimally Invasive Techniques for Total Aortic Arch Reconstruction. Methodist DeBakey Cardiovascular Journal. 2016; 12 (1): 41-44. DOI: https://doi.org/10.14797/mdcj-12-1-41
9. Turlyuk D.V., Yanushko V.A., Chernoglaz P.F., et al. Results of using hybrid technology in the treatment of arch and descending aortic aneurysms. Eurasian Heart Journal. 2016; 33 (1): 151-152. (in Russian)
10. Shlomin V.V., Gordeev M.L., Zverev D.A., et al. Hybrid treatment of patients with aneurysms and dissections of the aortic arch and descending portion of the thoracic aorta. Angiology and Vascular Surgery. 2017; 23 (4): 89-97. (in Russian)