Novel and Innovative Hybrid Technique for Type A Aortic Dissection
March 28th, 2025
The protocol describes ascending aortic replacement combined with endovascular coverage of the entire aortic arch with a fenestrated stent graft in a patient with acute type A aortic dissection in the absence of a tear in the aortic arch.
We replaced ascending aorta in TAAD patients without arch involvement and used self modified standard graft to preserve native arch branch, ensuring a successful procedures and rapid recovery. This procedure reduce the surgical steps of the traditional approach. It's easy to perform and avoid deep hypothermic circulatory arrest, reducing postoperative complications.
The aortic arch greater curvature was buried, allowing a less invasive approach to avoid circulatory arrest while preserving native branches. Custom modification in situ were required due to the left subclavian arteries, proximity to the bridge, ensuring branch perfusion. The aorta was measured at key points, including the ascending aorta, the aortic arch, and the descending thoracic aorta.
After selecting the appropriate artificial vascular graft, evaluating the aortic structures and administering heparin, extra corporeal circulation was established through the axillary and femoral arteries. Extra corporeal circulation was assisted to safely perform the surgical intervention. The ascending aorta was excised and a tailored artificial graft selected based on preoperative computed tomography angiography measurements, was sutured to replace the diseased aortic segment.
Concurrently, the aortic valve was replaced with a mechanical valve prosthesis to ensure a long-term hemodynamic stability. After replacing the ascending aorta, the chest was left open to facilitate subsequent evaluation of the distal anastomosis. Kelly clamps or titanium clips were placed at the location of the distal anastomosis to serve as clear anatomical reference points for imaging and subsequent surgical interventions.
Digital subtraction angiography was performed to assess the integrity and patency of the newly constructed aortic segment, and then the position and length of the stent graft openings were determined. To avoid endo leak and incomplete lesion management, inside two windowing was planned for the left subclavian artery to implant the VIABAHN and in vitro fenestration was performed for the remaining two arch branches. The anterior end of the stent was covered and extended beyond the distal aortic anastomosis by 10 to 15 millimeters.
The length of the stent graft window was defined using the proximal end of the brachiocephalic trunk osteum and the distal end of the left common carotid artery osteum. Fixed sutures made of radiopaque materials such as stainless steel wire or thin metal plates were used to position the window of the stent grafts with the corresponding branches of the aortic arch. Using interrupted or continuous sutures, the metal wire or sheet was carefully secured to the stent graft at the edges of the window.
Stable positioning and precise alignment with the arch vessels, particularly at the level of the brachiocephalic trunk and left common carotid artery were ensured to minimize the risk of restenosis or misalignment. After implanting the modified stent grafts through the femoral artery, the handle was rotated and the stent graft was released before slowly unsheathing it. The bracket was open to the starting position of the bracket overlay.
The opening side of the stent graft was identified by confirming the marker corresponding to the white dot on the handle. The anterior and posterior positions of the opening window were marked using the corresponding stent graft segments. The position of the aortic arch and its branches was determined by marking the aortic arch and two branches with screen markers and corresponding bone markers.
A guide wire was advanced through the sheath into the left subclavian artery under real-time fluoroscopy to ensure accurate catheter placement. A balloon catheter was introduced through the sheath and advanced to the osteum of the subclavian artery. Balloon dilatation was gradually performed at the site of the stent grafts to optimize stent expansion and restore blood flow in the dissected aorta.
A VIABAHN uncovered stent graft was deployed across the site to minimize the risk of endoleak and secure the position of the stent grafts. A second stent was implanted in the descending aorta to eliminate as much of the false lumen as possible. Digital subtraction angiography was performed to assess the outcome of the hybrid repair.
High resolution imaging of the entire aorta was obtained. After confirming the absence of leakage and successful stent graft placement, the chest was closed in layers by suturing the pericardium, re-approximating the chest wall muscles and fascia, and closing the skin while ensuring proper hemostasis to minimize postoperative complications. Postoperative computed tomography angiography imaging confirmed no significant contrast leakage, no stent dislodgement, and smooth blood flow in all three branches of the aortic arch indicating successful stent placement and stability.
Overview
This protocol outlines a surgical approach for ascending aortic replacement in patients with acute type A aortic dissection, utilizing a fenestrated stent graft for endovascular coverage of the aortic arch. The method aims to minimize surgical complications and enhance recovery.
Key Study Components
Area of Science
- Cardiovascular surgery
- Aortic dissection management
- Endovascular techniques
Background
- Acute type A aortic dissection poses significant surgical challenges.
- Traditional methods often involve deep hypothermic circulatory arrest.
- Innovative techniques can reduce surgical risks and improve outcomes.
- Preservation of native arch branches is crucial for hemodynamic stability.
Purpose of Study
- To describe a less invasive surgical technique for aortic replacement.
- To evaluate the effectiveness of a fenestrated stent graft in this context.
- To enhance postoperative recovery and reduce complications.
Methods Used
- Replacement of the ascending aorta with a tailored artificial graft.
- Use of digital subtraction angiography for intraoperative assessment.
- Deployment of a VIABAHN stent graft to secure the aortic arch branches.
- Postoperative imaging to confirm graft integrity and blood flow.
Main Results
- Successful replacement of the ascending aorta with minimal complications.
- Effective preservation of native arch branches and hemodynamic stability.
- No significant contrast leakage or stent dislodgement observed postoperatively.
- Enhanced recovery times compared to traditional methods.
Conclusions
- The described technique offers a viable alternative for managing acute type A aortic dissection.
- Utilizing a fenestrated stent graft can improve surgical outcomes.
- Further studies may validate the long-term benefits of this approach.
Frequently Asked Questions
Executive Industry Relevance
Hybrid surgical-endovascular techniques for acute type A aortic dissection address critical procedural risks and enable rapid intervention in high-mortality scenarios. This approach streamlines complex aortic repair, reducing neurological complications and procedural invasiveness, which is pivotal for translational device development and procedural innovation. The method's reproducibility and imaging-driven validation support its integration into advanced cardiovascular R&D pipelines.
Strategic Applications in Biopharma R&D
Early Discovery & Target Validation
- Enables mechanistic de-risking of device-tissue interactions in complex vascular repairs.
- Supports functional validation of fenestrated stent grafts for branch vessel preservation.
- Facilitates predictive confidence in procedural outcomes through intraoperative imaging.
Screening & Assay Development
- Establishes reproducible imaging endpoints for device performance assessment.
- Standardizes quantitative evaluation of graft placement and vessel patency.
- Enables scalable comparison of hybrid versus traditional surgical workflows.
Translational & Preclinical Research
- Aligns with disease-relevant models for acute aortic dissection intervention.
- Supports continuity from device concept to preclinical validation using imaging biomarkers.
- Provides risk-adjusted data for advancing hybrid repair strategies toward clinical translation.
Pipeline & Workflow Integration
This hybrid technique bridges early device validation and translational research, leveraging intraoperative and postoperative imaging for robust endpoint assessment.
- Discovery Biology: Clarifies procedural mechanisms and device-tissue compatibility in acute vascular injury models.
- Screening: Delivers reproducible, quantitative imaging outputs for device evaluation.
- Analytics: Utilizes digital subtraction angiography and CT angiography for objective performance metrics.
- Translational Research: Ensures procedural continuity and biomarker alignment from bench to preclinical models.
- Enterprise Reuse: Establishes a modular workflow adaptable to evolving device platforms and vascular indications.
Operational & Enterprise Impact
- Scientific Value: Increases predictive confidence and reduces mechanistic ambiguity in hybrid vascular interventions.
- Operational Value: Promotes standardization, reproducibility, and procedural scalability.
- Strategic Value: Enables informed go/no-go decisions and reduces late-stage procedural risk.
- Portfolio Impact: Supports risk-adjusted prioritization of device and procedural innovation programs.
Implementation Considerations
- Requires advanced surgical and endovascular expertise for procedural execution.
- Demands high-resolution imaging infrastructure for intraoperative and postoperative assessment.
- Necessitates cross-team standardization of device modification and imaging protocols.
- Adaptation may be limited by anatomical variability and device customization needs.
- Practical limitations include procedural complexity and the need for real-time imaging guidance.
