Risk factors for proximal and distal aortic events after type A acute aortic dissection

OBJECTIVES

Type A acute aortic dissection (TAAAD) is a life-threatening condition often requiring emergency surgery, with approximately 30% of patients needing reoperation. This study aimed to identify predictors of long-term aortic events from early postoperative computed tomography (CT) examinations.

METHODS

A total of 336 cases underwent TAAAD surgery at two institutions between 2002 and 2018. Of these, 302 patients received CT examinations immediately after initial TAAAD surgery. Predictors of aortic events were evaluated from these early postoperative CT exams. Aortic events were defined as any events involving aortic-related death, open surgery, reoperation, endovascular stenting, or thoracic aorta diameter enlargement to ≥ 55 mm.

RESULTS

Excluding 34 in-hospital deaths (10.1%; 34/336), the 1-, 5-, and 10-year actuarial survival rates after primary TAAAD surgery were 98.2%, 88.6%, and 81.7%, respectively. Over a mean follow-up period of 7.4 ± 5.1 years, 67 aortic events (proximal: 19, distal: 45, both: 3) were observed. Freedom from proximal aortic events was 98.6%, 93.9%, and 85.2% at 1, 5, and 10 years, respectively. Proximal anastomosis new entry was identified as a significant risk factor for aortic events, with a 92% vs. 42% incidence at 10 years (p < 0.001). Freedom from distal aortic events was 99.6%, 84.5%, and 67.2% at 1, 5, and 10 years, respectively. A false/true area ratio greater than 1 and distal anastomosis new entry were significant risk factors for aortic events (low-risk group: 83.3% vs. high-risk group: 42.3% at 10 years, p < 0.001).

CONCLUSIONS

Detailed analysis of early postoperative CT scans following primary TAAAD surgery may help identify predictors of subsequent aortic events, potentially improving long-term patient management and outcomes.

Early surgical outcomes in the composite-valve root replacement with bioprosthesis after surgery for acute type A aortic dissection

OBJECTIVES

This study aimed to evaluate the surgical outcomes of composite-valve root replacement with bioprosthesis (b-CVRR) after acute type A aortic dissection (AAAD) repair.

METHODS

We included 41 patients who underwent b-CVRR after surgery for AAAD from 2007 to 2022. We excluded seven patients with VSRR, three with mechanical valve use, one with mycotic aneurysm, and one with cardiopulmonary resuscitation.

RESULTS

The overlapping surgical indications for b-CVRR were pseudoaneurysm in 21 patients (51.2%), severe AI in 19 (46.3%), re-dissection in 15 (36.6%), root dilatation (> 50 mm) in 12 (41.5%), and rupture in 3 (7.3%). The coronary artery reconstruction methods were bilateral Carrel patch in 13 patients (32%), Carrel patch with Piehler in 16 patients (38%), bilateral Piehler in six patients (15%), and Piehler with coronary artery bypass (CABG) in six patients (15%). Four patients who underwent the Carrel patch technique required additional intraoperative CABG. Three hospital mortality occurred (7.3%; myonephropathic metabolic syndrome, heart failure, bleeding from the thyroid carotid artery without injury). No thrombosis of the reconstructed site was observed with the Piehler procedure.

CONCLUSION

Surgical outcomes for patients treated with b-CVRR after AAAD repair were acceptable. Intraoperative coronary artery events occurred due to stenosis caused by traction on the reconstructed coronary artery due to adhesions.

Traction-separation law parameters for the description of age-related changes in the delamination strength of the human descending thoracic aorta

Aortic dissection is a life-threatening disease that consists in the development of a tear in the wall of the aorta. The initial tear propagates as a discontinuity leading to separation within the aortic wall, which can result in the creation of a so-called false lumen. A fatal threat occurs if the rupture extends through the whole thickness of the aortic wall, as blood may then leak. It is generally accepted that the dissection, which can sometime extend along the entire length of the aorta, propagates via a delamination mechanism. The aim of the present paper is to provide experimentally validated parameters of a mathematical model for the description of the wall's cohesion. A model of the peeling experiment was built in Abaqus. The delamination interface was described by a piecewise linear traction-separation law. The bulk behavior of the aorta was assumed to be nonlinearly elastic, anisotropic, and incompressible. Our simulations resulted in estimates of the material parameters for the traction-separation law of the human descending thoracic aorta, which were obtained by minimizing the differences between the FEM predictions and the delamination force given by the regression of the peeling experiments. The results show that the stress at damage initiation, Tc, should be understood as an age-dependent quantity, and under the assumptions of our model this dependence can be expressed by linear regression as Tc =  - 13.03·10-4·Age + 0.2485 if the crack front advances in the axial direction, and Tc =  - 7.58·10-4·Age + 0.1897 if the crack front advances in the direction of the aortic circumference (Tc [MPa], Age [years]). Other model parameters were the stiffness K and the separation at failure, δf-δc (K = 0.5 MPa/mm, δf-δc = 0.1 mm). The material parameters provided by our study can be used in numerical simulations of the biomechanics of dissection propagation through the aorta especially when age-associated phenomena are studied.

[Endovascular Treatment of Aortic Dissection due to Suture Line Dehiscence after Aortic Graft Replacement for Type A Aortic Dissection: A Report of Two Cases]

Aortic anastomotic leak is an uncommon complication after ascending aortic replacement for acute aortic dissection. Redo-surgery is the traditional standard treatment despite high mortality and morbidity. Recently, endovascular treatment has been attempted as an alternative approach in a few case reports. Here, we present two cases of aortic anastomotic leak due to suture line dehiscence after aortic graft replacement for type A aortic dissection, which were successfully treated by coil with subsequent N-butyl cyanoacrylate embolization and an Amplatzer™ vascular plug.

Occurrence of pseudoaneurysm of the coronary button due to aortic remodeling after Bentall operation

Here, we present a case report detailing a pseudoaneurysm of the coronary button due to aortic remodeling that occurred 2 years after aortic root replacement. The patient was referred to our hospital with a diagnosis of left coronary artery pseudoaneurysm. Intraoperative findings revealed substantially loosened sutures in both the left and right coronary arteries with bleeding. Specifically, the left coronary artery was detached at the 6-9 o'clock positions. The operation was concluded with ligation of the loose suture and addition of a new suture. Chronic dissection thickened the aortic wall of the coronary artery ostium in the initial Bentall operation, whereas the sutured coronary button in this operation exhibited a normal arterial wall without a thickened dissected intima. This suggests that aortic wall remodelling of the coronary ostium leads to suture loosening and subsequent haemorrhage. Aortic wall remodeling may lead to bleeding or pseudoaneurysms during the remote period.

Novel reinforcement technique using pre-glued felt strip with Hydrofit® for a distal anastomotic site in acute type A aortic dissection

In the surgical treatment of acute type A aortic dissection, performing the anastomosis in the dissected aorta is technically challenging due to the fragility of the dissected aortic wall. This study describes the reinforcement technique for the distal anastomotic site, using pre-glued felt strips with Hydrofit®. No intraoperative bleeding occurred at the anastomosis site of the distal anastomosis stump. Postoperative computed tomography revealed no new distal anastomotic entry. This technique is recommended for managing acute type A aortic dissection during distal aortic reinforcement.

Total arch replacement: When and how?

Acute type A aortic dissection (ATAAD) is a life-threatening disease, which often causes cardiac tamponade, rupture, and malperfusion. ATAAD is associated with a high hospital mortality rate. Open aortic surgery for ATAAD is always required to save the patient, particularly elderly patients. Tear-oriented surgery is recommended as the frontline treatment for ATAAD, and hemiarch replacement (HAR) is sufficient because the primary entry is often observed in the ascending aorta (60%-70%). However, HAR has some drawbacks, such as new creation of an anastomotic entry and unfavorable distal aortic remodeling during long-term follow-up. Although total arch replacement (TAR) is a demanding procedure, it is another useful option for ATAAD. Proper patient selection for TAR is controversial. Standardized procedure for TAR, including the optimal brain protection methods and the use of excellent sealed vascular prosthetic grafts, has been established over the past decades. Therefore, TAR is increasingly being selected for HAR in patients who are young or have enlarged aortic arch, severely dissected supra-aortic arch vessels, or hereditary thoracic aortic disorders. The emerging technology of commercially available frozen elephant trunk accelerated the application of TAR, facilitates distal anastomosis, and improves distal aortic remodeling. Although further evidence is required, TAR could be the best choice for HAR for selected patients. Currently, appropriate selection of the surgical technique is important to maximize the benefits of open surgery for ATAAD.

Pseudoaneurysm with a fistula to the right ventricle late after surgical repair of type A aortic dissection in a patient with systemic lupus erythematosus

Background

Pseudoaneurysm with a shunt to the right ventricle after aortic repair for acute aortic dissection is an extremely rare and life-threatening condition. Surgical treatment is unavoidable, but surgery is complicated, and there are some pitfalls. This study describes the reoperation performed in a patient at a high surgical risk by clarifying the shunt site using multimodality imaging before surgery.

Case presentation

A 69-year-old woman with a history of systemic lupus erythematosus (SLE) and Sjogren’s syndrome presented with a pseudoaneurysm 1 year after emergency surgery for acute type A aortic dissection. Eight years after the first surgery, she experienced sudden chest pain and presented to the emergency department. Her dyspnea worsened; therefore, echocardiography and three-dimensional computed tomography (3DCT) were performed, and a pseudoaneurysm and shunt to the right ventricle were identified. The medical team attempted to close the shunt with a percutaneous catheter but was unsuccessful, and she was referred to our department for surgical treatment. The pseudoaneurysm originating from the proximal side of the aorta was large (diameter = 55 mm), and echocardiography-gated 3DCT identified the shunt from the pseudoaneurysm to the right ventricle. First, extracorporeal circulation was initiated, and resternotomy was performed. We could not insert the left ventricular venting tube from the right side because of the pseudoaneurysm size. Instead, the tube was inserted from the left atrial appendage. We found a half-circumferential disengaged anastomosis around the proximal anastomosis, which formed the large pseudoaneurysm leading to a fistula in the right ventricle. We closed the fistula and performed a Bentall operation. The patient had a good postoperative course and was discharged on postoperative day 21. She continued treatment for SLE and Sjogren’s syndrome, and her inflammatory reaction improved.

Conclusions

We performed a Bentall operation and fistula closure with resternotomy in a patient with type A aortic dissection with SLE and Sjogren’s syndrome. Multimodal imaging is essential in defining the pseudoaneurysm and the fistula surrounding the anatomy while ensuring their resolution and guiding the approach for operation.

Complete neck vessel preservation using a fenestrated stent graft for the treatment of proximal anastomotic leakage after open frozen elephant trunk graft aortic arch repair

We have reported a case of proximal anastomotic leakage excluded with the Najuta fenestrated stent graft after a surgeon-modified frozen elephant trunk aortic arch graft. The fenestrated stent graft was deployed at the zone 0 proximal site, preserving the cervical branches. Complete neck vessel preservation during endovascular repair using a Najuta fenestrated stent graft appears to be safe and effective for anastomotic leakage after aortic arch aneurysm repair.

Trans-catheter closure of aortic anastomosis leak after aortic replacement: classifications and techniques

Background

Aortic anastomotic leak (AAL) is knotty complication after aortic replacement. We aimed to evaluate the feasibility and efficacy of the techniques of trans-catheter AAL closure as well as to evaluate the impact of the new classification on the interventional closure.

Methods

From October 2015 to November 2017, 20 consecutive high surgical risk patients (mean age 47±12 years, 13 males) were referred to our center for trans-catheter closure AALs. Due to the variation of leak, we therefore developed a new-classification based on transesophageal echocardiography (TEE) and computed tomography angiography (CTA) assessments: type I: aorta-to-right atrium fistula, n=6; type II: pseudoaneurysm induced by a suture line dehiscence, n=4; type III: patency of the false lumen in aortic dissection, n=10. Outcomes were analyzed by assessing TEE and CTA in different types of AALs.

Results

Successful closure was accomplished in 17 subjects (85%). The severity of AAL reduced significantly in 15 patients (88%); two patients required a second procedure. At follow-up, we found that in type I, the right atrium systolic pressure reduced (from 25.3±4.1 to 7.0±1.2 mmHg) with the improved NYHA (3.5±0.6 vs. 1.0±0.0), the diameter of pseudoaneurysm significantly decreased (5.0±1.8 to 2.0±1.8 mm) in type II, and complete thrombosis was achieved in all type III patients.

Conclusions

Trans-catheter closure of AAL displays satisfactory results even in those defined as high-risk patients, and it could be considered be a viable alternative approach. New classification is helpful in decision-making.

The fate of the downstream aorta after open aortic repair for acute DeBakey type I aortic dissection: total arch replacement with elephant trunk technique versus non-total arch replacement†

OBJECTIVES

The aim of this study was to evaluate the fate of the downstream aorta following open aortic repair for acute DeBakey type I aortic dissection comparing total arch replacement (TAR) with the elephant trunk (ET) technique versus non-total arch replacement (non-TAR).

METHODS

From October 1999 to December 2016, 267 patients underwent open repair for acute DeBakey type I aortic dissection. A tear-oriented strategy was mainly used to determine the extent of graft replacement. Hospital mortality was 10.0% (12/120 patients) in the TAR group and 17.0% (25/147 patients) in the non-TAR group (P = 0.070). Late outcomes were compared in 230 hospital survivors (TAR: n = 108 and non-TAR: n = 122). Mean follow-up was 6.5 ± 4.6 years. The aortic diameters were measured at 4 levels, across 6 time points using computed tomography.

RESULTS

Freedom from additional aortic surgery for distal dilation was significantly better in the TAR group than the non-TAR group (TAR: 97.5 ± 1.8% at 5 years and non-TAR: 88.2 ± 3.4% at 5 years, P = 0.045). Freedom from a distal aortic event was also significantly better in the TAR group compared with the non-TAR group (TAR: 97.2 ± 1.6% at 5 years and non-TAR: 80.7 ± 4.2% at 5 years, P = 0.013). In the non-TAR group, the aortic arch diameter significantly increased (P < 0.001). Significant aortic remodelling occurred at the proximal descending aorta in the TAR with ET group (P < 0.001).

CONCLUSIONS

The TAR with ET reduced the need for additional distal aortic repair compared to non-TAR. TAR with ET prevented unfavourable aortic growth in both the aortic arch and the proximal descending aorta.

Locational impact of luminal communication on aortic diameter changes and reintervention in acute type I aortic dissection

OBJECTIVES

The aim of this study is to evaluate the locational impact of a luminal communication on aortic diameter changes and reintervention after surgical repair of acute type I aortic dissection.

METHODS

Between 2009 and 2017, 304 patients underwent operation for acute type I aortic dissection. Among them, 93 patients were enrolled. The luminal communications were analysed in segment 1 (the proximal descending thoracic aorta), segment 2 (the distal descending thoracic aorta) and segment 3 (the abdominal aorta). The aortic diameter was measured at the pulmonary artery bifurcation, coeliac axis, maximal abdominal aorta and maximal thoraco-abdominal aorta using serial follow-up computed tomography scans. The linear mixed model was used, and the rate of freedom from reintervention was analysed.

RESULTS

In the adjusted analysis, the initial diameter of the maximal abdominal aorta and the first luminal communication in segment 1 was statistically significant. However, the slope value of the maximal abdominal aorta was smaller than that of the first luminal communication in segment 1 (0.024 vs 0.198). The 3-year freedom from reintervention rate was significantly higher in patients without a luminal communication than in those with an initial luminal communication in segment 1 (96% vs 47%, log rank, P = 0.003).

CONCLUSIONS

A luminal communication at the proximal descending thoracic aorta (segment 1) is a significant factor for an increasing aortic diameter and reintervention after surgical repair of acute type I aortic dissection.

Reinforcement and reapproximation of the aortic stump during surgery for acute aortic dissection

Anastomosis of the fragile aortic wall in patients with acute aortic dissection presents a challenge to cardiovascular surgeons. Reinforcement of the stump is a key to accomplishing successful anastomosis. Surgical glues such as gelatin-resorcin-formalin (GRF) glue and Bioglue are easy to use and have radically changed the process of the reinforcement and reapproximation. However, as surgical glues have been associated with disadvantages such as tissue necrosis, enthusiasm for their use has waned. In this review, we discuss the various methods for reinforcement and reapproximation of the aortic stump during operations for acute aortic dissection, mainly outside the category of surgical glues.

Techniques and outcomes of secondary open repair for chronic dissection after acute repair of type A aortic dissection

Despite successful repair of acute type A aortic dissection (TAAD), the distal false lumen may remain patent resulting in progressive degeneration of the remaining distal aorta. This can lead to aneurysmal dilatation and risk of rupture. Open distal reoperation to replace the residually dissected thoraco-abdominal aorta may be accomplished with acceptable morbidity and mortality in experienced hands. This can be facilitated when the index operation for acute TAAD is tailored to exclude all primary tears and set the arch and descending aorta for a subsequent open, endovascular or hybrid procedure.

Spot Stenting of Supra-aortic Branch Vessels for Residual Type A Dissection

The purpose of this report was to describe the exclusion of the false lumen in a residual type A aortic dissection (TAAD) by the deployment of 2 covered stents: one in the right common carotid artery (RCCA) and one in the left subclavian artery (LSA). A 77-year-old female, already treated with ascending aorta replacement for acute TAAD, was referred to our center for a 97-mm post-dissection arch aneurysm. A computed tomography angiography (CTA) showed false lumen patency by reperfusion from secondary tears located at the level of RCCA and LSA. No primary aortic tear was noted. Under local anesthesia and by transfemoral percutaneous approach, the tears at the level of RCCA and LSA were covered by a 9-mm Viabahn stent graft (Gore, Flagstaff, AZ), and a 10-mm V-12 stent graft (Maquet, Rastatt, Germany), respectively. The false lumen was finally occluded by the deployment of a 6-mm vascular plug at the level of LSA re-entry tear, by left transbrachial puncture. The procedure was completed uneventfully. Twelve-month CTA showed exclusion of the false lumen, patency of all supra aortic trunks, and initial shrinkage of the aneurysm. Spot stenting of secondary re-entry tears, already described for visceral branches, seems to be safe and effective also for supra-aortic trunks in selected patients.

Autologous adventitial overlay method reinforces anastomoses in aortic surgery

In this study, we present an inexpensive and effective method for providing a secure and hemostatic anastomosis using autologous adventitia obtained from a dissected or aneurysmal wall. The resected aortic wall is separated between the adventitia and media, and a soft, 2 × 10-cm adventitial strip is overlaid to cover the anastomotic margin. A graft is sutured to the aortic stump. This autologous adventitial overlay method can inexpensively and strongly reinforce the anastomosis during aortic surgery for dissection or aneurysm and will contribute to anastomotic hemostasis and long-term stability.