Endovascular repair of ascending aortic diseases with custom-made endografts

Endovascular repair of ascending aortic pathologies in patients unfit for open surgery: case series and literature review

The number of vascular centers performing endovascular repair of ascending aortic disease is constantly increasing. Accordingly to the guidelines, open surgical repair remains the gold standard for these pathologies. However, approximately one quarter of patients are deemed unfit for open surgery. In this study, we describe three cases of ascending thoracic endovascular aortic repair (TEVAR) performed at our center. All the patients were deemed unfit for open surgery by the aortic team. Two patients had an ascending aortic pseudoaneurysm, and the third had a focal type A aortic dissection. In two cases, we used two abdominal aortic cuffs deployed from zone 0B to zone 0C, with no need for supra-aortic trunk debranching. In one case, we performed a "reverse" extrathoracic debranching, and we deployed a thoracic endograft from zone 0B to zone 2. Complications included one minor stroke and one inguinal hematoma. In one patient with an infected pseudoaneurysm, we performed ascending TEVAR as a bridge strategy for open repair. This patient developed a type Ia endoleak; however, clinical stabilization and infection control were obtained, and he was able to undergo heart surgery successfully. He underwent a second reintervention to treat superior mesenteric embolic occlusion. At 2 years of follow-up, all three patients were alive. Our preliminary experience demonstrates the technical feasibility and clinical appropriateness of ascending TEVAR using standard, commercially available endografts. However, no consensus has been reached regarding some critical aspects, such as the development of a standardized technique or the efficacy of the currently available devices. The improvements in graft design and the adoption of the "aortic team" approach could help in the near future to standardize the procedure, establish appropriate indications, and ensure good clinical outcomes.

Over 8-year survival after ascending endovascular repair of type A intramural haematoma

Acute type A aortic syndromes are catastrophic events whose management relies primarily on conventional surgery. For several years, various endovascular attempts have been described; however, long-term data are inexistent. We describe a case of stenting of the ascending aorta for a type A intramural haematoma with survival and freedom from reintervention at >8 years postoperatively.

Endovascular Management of the Ascending Aorta: State of the Art

Endovascular stent graft repair (EVAR) has revolutionized the management of aneurysms and dissections of the thoracic and abdominal aorta and is considered the first-line treatment in such pathologies. Initially designed for patients unfit for open repair, EVAR and thoracic endovascular aortic stent graft repair are associated with improved morbidity and mortality and a faster recovery process. The endovascular revolution of the aorta continues moving proximally, with fenestrated and branch stent grafts currently in clinical trials for the management of thoracoabdominal aortic aneurysms, and several branched thoracic devices are either approved or in trial for management of aortic arch pathologies. The final frontier in the endovascular management of the aorta is the aortic root and ascending aorta. The first early feasibility trial for management of type A aortic dissection has recently concluded with a multicenter phase 2 study slated for the spring of 2023. The following article updates the reader on the unique challenges of endovascular management of the ascending aorta and a look at the future technologies that will define this space.

Vascular Access Challenges in Thoracic Endovascular Aortic Repair: A Literature Review

BACKGROUND

This review aims to comprehensively summarize access challenges in thoracic endovascular aortic repair (TEVAR) by describing vascular access routes, associated risks, outcomes, and complications.

METHODS

A literature search was conducted utilizing the PubMed (Medline), Scopus, and Web of Science databases. Qualitative and quantitative data from selected studies are extracted and discussed according to available standards for narrative reviews.

RESULTS

In total, there were 109 eligible studies based on predefined inclusion- and exclusion criteria. There were 39 original articles or reviews and 57 case series or case reports. This article summarizes the evidence from these studies and discusses traditional retrograde access routes and techniques for TEVAR via a femoral or iliac route, with or without the use of conduits. Next, alternative antegrade access routes and techniques via a brachial, axillary, carotid, ascending aorta, transapical, transcaval, or another route are discussed. Vascular access complications are presented with specific attention to the importance of gender and alternative antegrade access routes.

CONCLUSIONS

Multiple access routes and techniques are currently available to overcome access challenges associated with TEVAR, based on low grade evidence from heterogeneous studies. Future research that compares different access routes and techniques might help in the development of a tailored access protocol for specific patients with challenging TEVAR access.

Endovascular repair of the ascending aorta: the last frontier

Different pathologies of the ascending aorta (AA), including aneurysms, acute and chronic dissections, and pseudoaneurysms, have been treated with open surgical repair with very good results, especially at aortic centers of excellence. There is, however, a subset of patients for whom open surgery is considered to pose high or prohibitive risk. These patients can benefit from a less invasive approach with catheters and wires, percutaneous techniques and stent grafts. However, the existing technology was developed to treat descending thoracic aortic pathologies; it is not approved for use in the AA by the US Food and Drug Administration (FDA). The devices used for the descending thoracic aorta (DTA) have certain size and design limitations that make their application to the AA cumbersome at times. As a result, custom-made endografts have been used to treat pathologies in the AA, although their use is feasible only in elective procedures. In addition, the AA has specific anatomic and physiologic characteristics that raise concerns about the long-term durability of the current technology. In this review, we outline the limitations, challenges and current status of endovascular technology to treat pathologies of the AA.

Endovascular Stent-Graft Repair of the Ascending Aorta: Assessment of a Specific Novel Stent-Graft Design in Phantom, Cadaveric, and Clinical Application

Purpose

To test a stent-graft specifically designed for the ascending aorta in phantom, cadaver, and clinical application, and to measure deployment accuracy to overcome limitations of existing devices.

Methods

A stent-graft has been designed with support wires to fixate the apices toward the inner curvature, thereby eliminating the forward movement of the proximal end which can happen with circumferential tip capture systems. The device was deployed in three aortic phantoms, and in four cadavers, deployment precision was measured. Subsequently, the device was implanted in a patient to exclude a pseudoaneurysm originating from the distal anastomosis after ascending aortic replacement.

Results

The stent-grafts were successfully deployed in all phantoms and cadavers. Deployment accuracy of the proximal end of the stent-graft was within 1 mm proximally and 14 mm distally to the intended landing zone on the inner curvature, and 2–8 mm distal to the intended landing zone on the outer curvature. In clinical application, the pseudoaneurysm could be successfully excluded without complications.

Conclusion

The novel stent-graft design promises accurate placement in the ascending aorta. The differential deployment of the apices at the inner and outer curvatures allows deployment perpendicular to the aortic axis.

Level of Evidence

No level of evidence.

Coil Embolization of Post-Traumatic Pseudoaneurysm of the Ascending Aorta

BACKGROUND Traumatic rupture of the ascending aorta is a life-threatening injury, with a survival rate of around 15% to 20%. Treatment with open surgical repair is the criterion standard. However, open surgical repair is associated with high mortality and morbidity in patients with multiple traumas. There are no systematic data on traumatic thoracic rupture and aorta rupture in a cohort of patients who had undergone partial or total replacement of the thoracic aorta. We can only speculate about the mechanisms and consequences of such an injury. Therefore, even unorthodox endovascular techniques are a welcome advancement in this field and should be considered, providing they do not compromise patient safety. CASE REPORT A 61-year-old man presented with polytrauma after a fall from height. Since the patient had a history of a Bentall procedure, hypertension, coronary disease, and nicotinism, we quickly excluded open surgery as a treatment option. However, the patient's condition, additional injuries, and anatomical features prompted us to perform coil pseudoaneurysm, reducing his operative trauma and allowing for his faster recovery and early rehabilitation. The patient has remained under careful clinical supervision. The result of the patient's 1-year follow-up was satisfactory. CONCLUSIONS In this case, the endovascular approach was an effective, if temporary, option to open or hybrid surgery. This demonstrates that minimally invasive surgery can be helpful in some patients and can also be helpful as a bridge therapy. A good rapport between the surgeon and the patient is crucial to understanding the advantages and disadvantages of such treatment.

Treatment of a massive pseudoaneurysm originating from the ascending aorta with an off-the-shelf stent graft

A 73-year-old patient who underwent an emergency coronary bypass surgery in our institution and who required postoperative extracorporeal membrane oxygenation support in December 2019 presented in August 2020 with a rapidly growing subxiphoidal, pulsating swelling. A computed tomography scan revealed a massive mediastinal pseudoaneurysm originating from an 8-mm Dacron graft that was sutured to the ascending aorta during the index surgery for arterial extracorporeal membrane oxygenation cannulation. Due to the location and extent of the pseudoaneurysm, an open surgical revision was deemed high risk. Because no bypass conduit originated from the ascending aorta, we decided to occlude the entry of the pseudoaneurysm with a stent graft. Also, urgency did not allow for the manufacturing of a custom-made device, so an off-the-shelf stent graft had to be implanted. Currently, the only off-the-shelf thoracic stent graft with a length suitable for the ascending aorta (<7 cm) is the Medtronic Valiant Navion prosthesis, of which 2 prostheses (37 mm × 52 mm; covered seal) were successfully implanted to exclude the pseudoaneurysm. A follow-up computed tomography scan performed 4 months postoperatively showed no perfusion and regression of the pseudoaneurysm. With the growing number of reports describing stent graft placement in the ascending aorta, more off-the-shelf stent grafts suitable for the ascending aorta are desirable.