Achievements and prospects in endovascular treatment of aortic aneurysms / 中华普通外科杂志

In recent years, endovascular treatment has emerged as the preferred approach for aortic aneurysms. From an anatomical perspective, the current focus of research remains on the reconstruction of iliac artery branches, multiple branches of visceral arteries, and branches of the aortic arch. Substantial clinical evidence has been accumulated in these areas. Simultaneously, future research is expected to explore the reconstruction of the aortic root involving coronary arteries openings and the inhibition of small arterial aneurysm progression through pharmacological means. This article aims to provide a review of significant research data in recent years related to the treatment of aortic aneurysms, offering insights and prospects for future research directions.

Clinical application and efficacy analysis of castor stent graft in the treatment of aortic diseases / 中华胸心血管外科杂志

Objective:To summarize the use of Castor stent graft in aortic diseases and to analyze their efficacy.Methods:The clinical data of patients with aortic diseases treated with Castor stent graft from November 2017 to August 2022 in Fujian Provincial Hospital were collected and divided into branched stent group and branched stent co-operative group according to the operation method, and the clinical data of both groups were summarized.Results:A total of 75 cases of aortic disease were treated with Castor stents, and finally 53 cases were classified as branched stent group and 22 cases as branched stent co-operative group. The operations in both groups were successful. The median operative time in the branched stent group was 120(100, 160)min, and the median postoperative hospital stay was 7.0(5.5, 10.5)days.There was no postoperative ischemic stroke, no spinal cord ischemia. One case of new aortic dissection occurred. During follow-up, there was one lost case and two deaths, and the rest did not have endoleak, branch stent stenosis, ischemic stroke or re-intervention. In the branched stent co-operative group, there was one postoperative ischemic stroke, one case of slight stenosis of the left subclavian artery stent during follow-up, the remaining cases had satisfactory postoperative outcomes.Conclusion:Castor stent graft is a safe and effective procedure in the treatment of aortic diseases. And Castor stent graft can be used in combination with other endovascular repair techniques in the treatment of complex aortic diseases, with safe and reliable postoperative outcomes.

A Case of Open Graft Replacement for Abdominal Stent Graft Infection Caused by Cholecystitis / 日本心臓血管外科学会雑誌

A 67-year-old man underwent endovascular aneurysmal repair for an abdominal aneurysm at another hospital about a year earlier. He presented to us with complaints of abdominal pain with an accompanying fever. Contrast-enhanced CT revealed a stent graft thrombus, with discontinuity of the aneurysmal wall, and a mass in the left retroperitoneal space, suggesting stent graft infection. The patient's fever initially subsided with antibiotic treatment, but soon recurred. Plain CT revealed an enlarged left retroperitoneal mass, which was determined to be a contained aneurysmal rupture. The stent graft was surgically removed urgently without incident and, upon examination of the removed stent graft, it was noted that there was a section of yellowish-white tissue attached to the stent graft and definitive evidence of infection was apparent. Thorough debridement of the aneurysmal wall was performed, leaving a segment of the posterior wall intact. In-situ reconstruction was carried out using a Gelsoft graft soaked in rifampicin. There was evidence of purulent pus outflow and cholecystitis during the ablation procedure of the hepatic flexure for omental filling. Post cholecystectomy, the reconstructed vascular graft was covered with omentum. A bacterium, Bacteroides thetaiotaomicron, was detected in the pus, bile, and on the stent graft removed during the surgical procedure. Subsequently, a diagnosis of hematogenous stent graft infection during the course of acute cholecystitis was made. The postoperative course of the patient was uneventful, with no recurrence of infection observed in the 3 months following surgical intervention.

Placement of an Open Stent Graft for Treatment of a Distal Aortic Arch Aneurysm and Migrated Stent Graft Nine Years after TEVAR for Stanford Type B Dissection / 日本心臓血管外科学会雑誌

A 76-year-old man who underwent thoracic endovascular aortic repair (TEVAR) of an early chronic phase of Stanford type B dissection developed a 71 mm distal aortic arch aneurysm in conjunction with the migration of its proximal end over 9 years of follow-up. The proximal end of the graft had migrated 7 cm distal to the takeoff of the left subclavian artery. The patient underwent total arch replacement with an open stent graft which was connected with the TEVAR graft. He was discharged home 15 days after surgery without complications.

Efficacy and safety of branched stent and fenestrated stent for thoracic aortic diseases in short landing zone / 中华放射学杂志

Objective:To compare the efficacy and safety of Castor single-branch stent and in vitro fenestration stent in treating thoracic aortic diseases with insufficient landing zone.Methods:The clinical data of patients with thoracic aortic diseases treated with Castor single-branch stent or in vitro fenestrated stent between December 2017 and June 2021 in the First Affiliated Hospital of Zhengzhou University were retrospectively analyzed. A total of 184 patients were included, 99 patients were treated with Castor branch stent, and 85 patients with in vitro fenestration stent. All patients′ general clinical data, surgical data, perioperative and follow-up clinical and imaging data, and postoperative complications were collected. The χ2 test was used to compare the incidence of complications between the two groups, and the Kaplan-Meier method was used to plot the survival rate without adverse events between the two groups. Results:Stent placement was successful in all patients, and the success rate of the technique was 100%. Other branches were reconstructed in 2 patients in the Castor group and double fenestrated stent were reconstructed in 12 patients in the fenestrated group. The mean operation time of the Castor group was significantly shorter than that of the fenestrated group, the number of patients who received local anesthesia was significantly lower than that of the fenestrated group, and the endoleak rate during follow-up was significantly lower than that of the fenestrated group ( P<0.05). There was no significant difference in the postoperative hospital stay, the incidence rate of perioperative complications, mortality, the incidence rate of neurological complications, new dissection or aneurysm rate, branch stent stenosis rate, second surgical intervention rate, and false lumen thrombosis between the two groups ( P>0.05). The adverse event-free survival rate of the Castor group was slightly higher than that of the fenestrated group, but its difference was not statistically significant ( P>0.05). Conclusion:Castor branch stent and in vitro fenestration stent have good short-term and mid-term efficacy in the treatment of aortic diseases with insufficient landing zone, which are safe and effective options for reconstruction of LSA and other branch arteries.

A Case of Effective Zone 0 TEVAR Using Squid-Capture Assisted in situ Stent-Graft Fenestration, for Endoleak from the Fenestration of Najuta / 日本心臓血管外科学会雑誌

We report the case of a 76-year-old man who developed type IA endoleak through the fenestration after 1-debranch TEVAR using a Najuta endograft. The patient was admitted with expansion of the aneurysm after TEVAR, for additional therapy. Type IA endoleak through a fenestration has remained a significant clinical concern and its treatment is challenging. We performed Zone 0 TEVAR using the “Squid-Capture” technique assisted in situ stent-graft fenestration. Cerebral vessels were perfused by a percutaneous cardiopulmonary support system during in situ stent-graft fenestration, and the cerebral branch was clamped at the proximal site. It is difficult to operate the catheter inside the endoskeleton structure of a Najuta endograft, but several innovations were effective. Test dilation of the balloon catheter was performed to ensure that the wire did not interfere with the endoskeleton. Avoiding interference with the endoskeleton is important. The Squid-Capture technique allows safe and secure puncture of the graft. The operation was completed successfully. After this procedure, the endoleak disappeared. It is considered to be a useful method for treatment of endoleak through the fenestration.

Stent-Graft Infection with Severe Pulmonary Adhesion Cured by Extra-Anatomical Bypass through the Anterior Position of the Pulmonary Hilum: a Case Report / 日本心臓血管外科学会雑誌

This is a case of an 81-year-old male who underwent stent-graft (SG) placement for type B aortic dissection at the age of 79. Two and a half years after the surgery, he was diagnosed with SG infection. Although he was scheduled for SG removal and the in-situ replacement of the descending aorta, he had difficulty maintaining oxygenation under single lung ventilation and detaching the severe adhesion of the aneurysm to the lung; therefore, only the aneurysm sac was opened, and abscess drainage was performed. The continuous irrigation and drainage of the aneurysm sac were performed, but the infection did not improve. On the 6th day after the surgery, the aortic aneurysm in the lung adhesion area was left untreated, and an extra-anatomical bypass was performed from the distal aortic arch to the anterior position of the pulmonary hilum, anastomosing with the abdominal aorta. All SGs were removed, the abscess and intima of the aortic aneurysm were extensively excised, and the remaining cavity was filled with omentum. The infection rapidly improved after the surgery, and he was discharged on the 52nd day after admission. Fortunately, the infection did not recur for 2 years since the surgery. This procedure is useful as an option for surgical reconstruction for stent graft infection for which in-situ descending aorta replacement is difficult.

Influences of Morphological Characteristics of Modular Inner Branched Stent Graft on Hemodynamic Performance of Stent / 医用生物力学

Objective To study the effect of morphological characteristics of modular inner branched stent graft (MIBSG) on hemodynamic performance of postoperative aortic arch based on parameterized MIBSG model. Methods The fluid-structure interaction model of blood-MIBSG coupling performance was solved, and the effects of stent branch angles, stent diameters on hemodynamic characteristics were analyzed. Results With the increase of angles between branch stent and aortic arch stent, blood flow within the branch decreased, but the stress and displacement increased. With the decrease of stent diameters, blood flow perfusion decreased significantly, but the stress and displacement increased first, and then decreased. Conclusions The morphological changes of MIBSG not only have an impact on blood perfusion rate of branch stent, but also affect the stress exerted on stent and the corresponding displacement. Before application in clinic treatment of aortic arch diseases, the movement and torsion of MIBSG should been taken into full account in operation plan according to the actual situation.

A Case of Paraplegia after Total Arch Replacement with Frozen Elephant Trunk for Acute Type A Aortic Dissection / 日本心臓血管外科学会雑誌

The frozen elephant trunk technique (FET) for the treatment of acute aortic dissection is associated with more favorable remodeling in the descending aorta compared to those patients without FET, but it may also be associated with postoperative spinal cord injury (SCI) and actually,some postoperative SCI cases after FET are reported. Several risk factors for SCI are known and one of them is due to the occlusion of intercostal arteries from false lumen. A 71-year-old woman underwent total arch replacement with FET, but after surgery, she noticed decreased movement in both lower extremities and was suspected of postoperative paraplegia. She went through cerebrospinal fluid drainage but didn't get better at all. According to the preoperative contrast computed tomography images, seven out of ten intercostal arteries were originating from the false lumen and six of them were occluded after surgery. When most of intercostal arteries are originating from the false lumen and there is no entry inside the descending and abdominal aorta, the intercostal arteries may be occluded due to thrombosis of the false lumen and it may cause spinal cord ischemia after surgery.

Two Cases of Thoracic Endovascular Aortic Repair Using the Carotid Artery as the Access Route / 日本心臓血管外科学会雑誌

Thoracic Endovascular Aortic Repair (TEVAR) is widely used for high-risk patients with thoracic aortic pathology. However, access to the thoracic aorta can be difficult because TEVAR requires the introduction of a large a sheath especially in those with aortoiliac occlusive diseases and thoracic shaggy aorta. We herein report two cases of TEVAR in which the common carotid artery was used as the access route. Case 1 : An 86-year-old male patient whose past surgical history was significant for infected abdominal aortic aneurysm with abdominal aortic stump closed and axillo-bilateral femoral bypass. Computed tomography revealed a saccular aneurysm of the descending aorta, which required a carotid artery approach as the access route. Case 2 : A 79-year-old female patient who developed type A thoracic aortic dissection. She was considered to be of prohibitive risk for surgical repair and was treated conservatively. However, an intramural hematoma with an ulcer-like projection lesion in the ascending aorta expanded and definitive treatment was indicated. Because the descending aorta was significantly shaggy, we decided to perform TEVAR via the right common carotid artery as the access route. Both patients' pathology was successfully treated and were discharged without any complications. TEVAR via common carotid artery access is a useful and safe procedure for patients in whom femoral and abdominal aortic aorta access is not feasible or safe.

Saccular Aortic Arch Aneurysm with Kommerell's Diverticulum / 日本心臓血管外科学会雑誌

The patient was a 73-year-old man who was referred to our hospital due to an abnormal thoracic shadow. CT scans revealed Kommerell's diverticulum and saccular aortic arch aneurysm accompanied by abnormal origins of the right aortic arch and the left subclavian artery. Although there were no subjective symptoms, a surgical operation was planned considering the risk of a rupture of the saccular aneurysm. For the surgery, a median sternotomy approach was employed. Under cardiopulmonary bypass, the aortic arch was detached using the open distal method. Further, an open stent graft was inserted, and the aortic arch was replaced with a four-branched artificial blood vessel. After weaning off the cardiopulmonary bypass, coil embolization was performed on the left subclavian artery, and the site was checked to ensure that there was no endoleak. Although hoarseness was noted postoperatively due to paralysis of the right vocal cord, the patient progressed without any other major complications and was discharged 30 days after the operation.

A Case of Placement of the Reversed Gore Exclucder Contralateral Leg for Isolated Left Iliac Mycotic Artery Aneurysm / 日本心臓血管外科学会雑誌

A 49-year-old female with ruptured left common iliac mycotic arterial aneurysm (Lt. CIAA) was brought to our hospital as an emergency case. In Japan, endovascular treatment is unsuitable for the treatment of mycotic aneurysms, but findings from a Swedish national database showed that there was no difference in the long-term prognosis lasting over 10 years. Therefore, we performed endovascular aortic repair (EVAR) and saved the patient's life. The diameter of the proxymal sealing zone was larger than that of the distal zone. We used the Gore Excluder leg, which was inverted and implanted to match the caliber. Percutaneous abscess drainage was also performed on postoperative day 7 when hemostasis was confirmed for early infection control. The patient was discharged at 8 weeks postoperatively. After discharge from the hospital, oral antibiotics were continued until 6 months after the surgery. Six months postoperatively, contrast-enhanced computed tomography showed that the abscesses have disappeared. Blood samples that were taken at one month after the completion of antibiotics showed no evidence of the recurrence of infection and a curative course was achieved.

Short-term outcome of ascending aorta replacement combined with total aortic arch fenestration technique for acute type A aortic dissection / 中国胸心血管外科临床杂志

@#Objective    To report our clinical experience and outcomes of thoracic endovascular aortic repair (TEVAR) for acute Stanford type A dissection using ascending aorta replacement combined with implantation of a fenestrated stent-graft of the entire aortic arch through a minimally invasive technique. Methods    From 2016 to 2020 in our hospital, 24 patients (17 males and 7 females, aged 45-72 years) with complicated Stanford type A aortic dissection, underwent replacement of the proximal ascending aorta with TEVAR. None of the patients with dissection involved the three branches of the superior arch, and all patients were replaced with artificial blood vessels of the ascending aorta under non-hypothermic cardiopulmonary bypass, preserving the arch and the three branches above the arch, and individualized stent graft fenestration. Results    Surgical technical success rate was 100.0%. There was no intraoperative complication or evidence of endo-leak in 1 month postoperatively. Hospital stay was 10±5 d. During postoperative follow-up, the stent was unobstructed without displacement, the preserved branch of the aortic arch was unobstructed, and the true lumen of the descending aorta was enlarged. Conclusion     This hybrid technique by using TEVAR with fenestrated treatment is a minimally invasive and effective method to treat high-risk patients with acute Stanford type A aortic dissection.

Temporal Hemostasis with Kampo Medicine for Bleeding Due to Enhanced Fibrinolytic Type of Chronic Disseminated Intravascular Coagulation : A Case Report / 日本東洋医学雑誌

A 74-year-old woman presented to our clinic with a history of vascular-and stent-graft insertion for aortic dissection developed a tendency to bleed from a palmar wound due to chronic disseminated intravascular coagulation (DIC). Initially, she sustained the palmar wound due to a fall. On the second day after the injury, she experienced continuous bleeding and consulted the orthopedic department of a general hospital, where her dressing was changed. On the third day after injury, she sought consultation at our clinic. The clot and wound remained intact even 12 days after the injury. Therefore, the clot was removed and the bleeding was stopped surgically. On the same day, 5 hours after the surgical treatment, the patient presented to our clinic because of continuous bleeding. She was then administered kyukikyogaito and kamikihito to stop the bleeding. Her laboratory findings revealed thrombocytopenia, and additional inspection was performed. The bleeding stopped on the next day. On the third day after administration, the bleeding remained controlled and an additional inspection revealed DIC. In the cardiology hospital, the cause of tendency to bleed of chronic DIC was pointed out as being due to a leakage at the end of the stent-graft. Kampo medicine was thought to be useful for temporal hemostasis for bleeding due to chronic DIC.

Stress Analysis of Aortic Vessels under Stent Graft / 医用生物力学

Objective To simulate the interaction between the stent graft (SG) and the aortic wall with finite element (FE) analysis by considering the influence of residual stress field, so as to study the stent influence on stress distributions of the aortic wall. Methods The three-dimensional (3D) residual stress field was generated in an idealized bi-layered thick-wall aortic model via a stress-driven anisotropic growth model by reducing the transmural stress gradient. Upon virtually deploying the SG, the stress on the aortic wall was calculated. Results The 3D residual stress field, corresponding to an opening angle of 117.5°, was shown to reduce the transmural stress gradient in both the circumferential and axial directions. The maximum stress was found at the contact area between aortic wall and wave peak of the stent. At 20% oversize ratio of the stent, the maximum stresses on the aortic wall in circumferential and axial direction were 412 and 132 kPa, respectively, while the in-plane shear stresses σrθ and σrz were both 78 kPa. Under residual stress, the maximum radial, circumferential and axial stresses were decreased by 14.9%, 40.5% and 33.8%, respectively, while the maximum shear stresses σrθ ，σrz，σθz were reduced by 2.5%, 7.1% and 27%, respectively. With the increase of oversize ratio from 10% to 20%, the maximum radial, circumferential and axial stresses were increased by 316%, 129% and 41%, respectively, while the maximum shear stresses σrθ ，σrz，σθz were increased by 661%, 450% and 466%, respectively. Conclusions The residual stress can effectively reduce the transmural stress gradient. Both the residual stress and the oversize ratio of the stent play an important role in modulating the wall stress distribution and the maximum stress.

Examination of Treatment for Complications of the Downstream Aorta after a Frozen Elephant Trunk Procedure during the Follow-up Period / 日本心臓血管外科学会雑誌

Objective: We examined complications of the downstream aorta after the frozen elephant trunk (FET) procedure. Methods: Complications were diagnosed in eight patients: true aneurysm alone in five patients; type A aortic dissection in two patients; and both true aneurysm and type B aortic dissection in one patient. Results: Elective surgery was performed in seven patients. Five patients received a Matsui-Kitamura stent graft (MKS) and three patients received a J Graft Open Stent Graft (JGOSG). The FET procedure was successfully applied in all cases. Over the long term, dilatation of the descending thoracic aorta (dTA) alone was identified in two patients and dilatation of the dTA and migration was identified in three patients using the MKS. Complications of graft kinking and migration were seen in one patient and distal stent graft-induced new entry in two patients using the JGOSG. Thoracic aortic stent graft repair was successfully performed for complications in seven patients. Conclusion: For the improvement of clinical results, FET devices need to offer flexibility and appropriate radial force.

An elephant trunk stent graft strayed into the false lumen leading to a death during the Sun's operation: A case report / 中南大学学报(医学版)

Type A aortic dissection (AD) is a critical and severe disease with high mortality. The Sun's operation is a standard surgical method for this kind of disease at present. For the procedure, an elephant trunk stent is inserted into the true lumen of the descending aorta and the aortic arch is replaced. A patient was admitted to the First Hospital of Lanzhou University due to sudden chest and back pain for 6 days. Computed tomography angiography (CTA) showed type A AD. Ascending aorta replacement, Sun's operation, and ascending aorta to right femoral artery bypass grafting were performed. After surgery, the patient's condition was worsened. The digital subtraction angiography (DSA) showed the elephant trunk stent was inserted into the false lumen of AD, leading to the occlusion of the large blood vessel at the distal part of the abdominal aorta and below. Although we performed intima puncture and endovascular aortic repair, the patient was still dead.

Stent graft infection after endovascular repair of abdominal aortic aneurysm: a case report and literature review

Aortic end graft (EVAR) infection isa challenging management problem in aortic surgery with 0.2% to 0.7% incidence, which is similar to aortic graft infection after open abdominal aortic aneurysm (AAA) repair. Although much attention has been given to the more common problem of endo leak management, yet only sporadic case reports have been reported about the late complication of endograft infection. We reported a case of elderly Saudi male, known to have multiple medical problems presented to our emergency department with severe progressive abdominal pain, vomiting, and fever over the last 7 days. He was evaluated and diagnosed as septic shock due to and infected stent graft following Endovascular Aneurysm Repair of abdominal aortic aneurysm, 4 years ago, with peritonitis. He underwent emergency laparotomy and a left paraaortic abscess was drained and a part of exposed metals of the stent graft found. Other intraperitoneal abcesses were drained and abdomen closed over drains. Patient remained under ICU care, but unfortunately deteriorated and died 3 days postoperatively.

Interventional treatment with covered stent graft for retrograde Stanford type A aortic dissection and intramural hematoma: A systematic review and meta-analysis / 中国胸心血管外科临床杂志

@#Objective    To evaluate the prognosis of interventional treatment with covered stent graft for retrograde Stanford type A aortic dissection and intramural hematoma by single-arm meta-analysis. Methods    Related studies on treating retrograde Stanford type A aortic dissection and intramural hematoma with covered stent graft were retrieved from the databases by computer, including PubMed, EMbase, The Cochrane Library, Wanfang Data, VIP, CNKI and CBM, from inception to January 2020. Literatures were screened by researchers step by step according to the predefined inclusion and exclusion criteria. Quality of the enrolled literatures was evaluated, and data were extracted from the included studies. Afterwards, single-arm meta-analysis was carried out by the R3.6.3 software. Results    A total of 12 English and 5 Chinese studies were included, which were all case series, and the quality of all literatures was moderate evaluated by Newcastle-Ottawa Scale (NOS). After analyzing the clinical prognosis of 260 patients, the 30-day mortality was 6% (95%CI 0.04 to 0.11, P=0.97), the late mortality was 8% (95%CI 0.05 to 0.14, P=0.78), the incidence of endoleak was 21% (95%CI 0.16 to 0.29, P=0.06), the incidence of stroke was 5% (95%CI 0.03 to 0.09, P=0.99), the incidence of new aortic dissection was 7% (95%CI 0.04 to 0.11, P=0.96), the incidence of dissection progression was 10% (95%CI 0.07 to 0.16, P=0.24), and the absorption rate of intramural hematoma was 84% (95%CI 0.37 to 1.00, P<0.01). Conclusion    Interventional treatment with covered stent graft for retrograde Stanford type A aortic dissection and intramural hematoma can obtain good early treatment results for some patients, and can be used as a safe and effective treatment for aged patient with high risk who cannot tolerate surgery. Endoleak, stroke and new aortic dissection are the early serious complications of this method.

Finite element simulation of stent implantation and its applications in the interventional planning for hemorrhagic cardio-cerebrovascular diseases / 生物医学工程学杂志

Numerical simulation of stent deployment is very important to the surgical planning and risk assess of the interventional treatment for the cardio-cerebrovascular diseases. Our group developed a framework to deploy the braided stent and the stent graft virtually by finite element simulation. By using the framework, the whole process of the deployment of the flow diverter to treat a cerebral aneurysm was simulated, and the deformation of the parent artery and the distributions of the stress in the parent artery wall were investigated. The results provided some information to improve the intervention of cerebral aneurysm and optimize the design of the flow diverter. Furthermore, the whole process of the deployment of the stent graft to treat an aortic dissection was simulated, and the distributions of the stress in the aortic wall were investigated when the different oversize ratio of the stent graft was selected. The simulation results proved that the maximum stress located at the position where the bare metal ring touched the artery wall. The results also can be applied to improve the intervention of the aortic dissection and the design of the stent graft.