Transcatheter Aortic Valve Replacement in a Patient With Right-Side Dominant Double Aortic Arch

It was already known that double aortic arch (DAA) represents a rare congenital vascular malformation typically identified during pediatric diagnostic evaluations for respiratory distress or dysphagia. This anatomical variant involves the persistence of both embryonic fourth branchial arches, creating a vascular ring that encircles the trachea and esophagus in a restrictive manner. While often symptomatic in infants, some individuals remain undiagnosed until adulthood when secondary cardiovascular pathologies like severe aortic stenosis necessitate complex endovascular intervention. Adult presentations of this anomaly complicate standard endovascular procedures due to the atypical branching patterns and significantly increased vessel tortuosity within the thoracic cavity. Interventionalists frequently encounter difficulties when navigating delivery systems through these non-standard thoracic configurations, which lack the predictable geometry of a normal left-sided arch. The presence of a right-side dominant arch further alters the expected trajectory for catheters entering from the femoral access points, requiring unconventional maneuvering. This absence of evidence motivated the documentation of procedural strategies for managing severe aortic stenosis in the presence of complex vascular rings.

This case report evaluates the procedural efficacy of a snare-assisted approach for valve deployment in a patient with a right-side dominant double aortic arch. The clinical team sought to overcome the physical barriers posed by extreme arch curvature that prevented standard delivery system advancement during the transcatheter procedure. Investigators aimed to describe the specific anatomical challenges encountered during the preprocedural evaluation of a 71-year-old female with comorbid end-stage renal disease (ESRD). The report details the decision-making process regarding vascular access sites and the selection of specialized wire techniques to navigate the bifurcated aortic structure. Researchers intended to provide a practical framework for interventionalists facing similar structural anomalies during transcatheter aortic valve replacement (TAVR) in geriatric populations. This documentation serves to highlight the limitations of conventional cerebral embolic protection (CEP) devices when confronted with the unique branching of a double arch. The study seeks to validate the use of snare-assisted techniques as a reliable rescue strategy when standard endovascular approaches fail due to severe arch tortuosity.

Clinicians performed a comprehensive preprocedural assessment using multi-detector computed tomography (MDCT) to map the patient's unique thoracic vasculature and identify the dominant arch segment. The surgical team selected the right femoral artery for primary access because it offered the most favorable vessel diameter for the large-bore delivery sheath required for the valve. Initial attempts to cross the complex arch utilized a double-stiff wire technique to provide sufficient mechanical support for the advancement of the transcatheter valve system. When standard wire configurations failed to negotiate the sharp angulation of the right-sided arch, the operators introduced a snare-assisted approach to guide the catheter tip. This rescue maneuver involved capturing the delivery system tip from a secondary access point to provide the necessary tension for successful navigation through the tortuous segment. The procedural protocol also included an attempt to deploy a cerebral embolic protection (CEP) device to mitigate the risk of perioperative neurological events during the valve implantation. Operators monitored the patient's hemodynamic status throughout the intervention to ensure that the prolonged navigation time did not compromise cardiac output or renal perfusion.

The surgical team achieved successful valve deployment only after implementing the snare-assisted technique to bypass the severe tortuosity of the right-side dominant double aortic arch. The double-stiff wire method proved insufficient for advancing the delivery system, highlighting the mechanical limitations of standard TAVR hardware in patients with congenital vascular rings. Imaging confirmed that the right-side dominant arch created a pronounced curvature that obstructed the natural trajectory of the transcatheter device toward the aortic annulus. Although the prosthetic valve was positioned correctly with good hemodynamic results, the patient subsequently experienced a postprocedural stroke during the recovery period. The anatomical complexity of the vascular ring prevented the optimal placement of cerebral embolic protection (CEP) filters, which likely contributed to the neurological complication. These findings demonstrate that while snare assistance facilitates valve delivery, it does not fully eliminate the heightened risks associated with congenital arch anomalies in elderly patients. The patient's end-stage renal disease and the associated vascular calcification may have further complicated the navigation and increased the risk of embolic debris release.

Comprehensive preprocedural imaging remains essential for identifying incidental congenital anomalies that could derail endovascular interventions in patients with severe aortic stenosis. Snare-assisted techniques provide a viable alternative for navigating the delivery system when standard wire supports fail in the presence of extreme thoracic vessel tortuosity. The presence of a double aortic arch significantly complicates the use of adjunctive tools like cerebral embolic protection (CEP) systems due to atypical vessel origins. Future procedural planning for geriatric patients with vascular rings must account for the increased risk of embolic events and the potential failure of standard protection devices. This case underscores the necessity of individualized strategies in the management of structural heart disease when comorbid with rare congenital vascular defects. Clinicians should consider the mechanical constraints of current TAVR delivery systems when treating patients with right-side dominant arch variants to optimize procedural outcomes. The study emphasizes that anatomical success in valve placement does not guarantee the absence of neurological complications in patients with complex vascular rings.