Transradial Flow-Diverting Stent Placement Through an Arteria Lusoria: 2-Dimensional Operative Video.

To the Editor: We would like to thank the authors of the recent letter to the editor for their interest in our article describing our approach to a patient with an aberrant right subclavian artery (ARSA) who received flow-diverting stent therapy through right transradial access (TRA).1,2 ARSA, or arteria lusoria, is one of the most common aortic arch anomalies, observed in 2% of the general population, and has even higher rates in patients with Down syndrome.3 Further discussion and research on the approach to this anomaly is needed; as such, we appreciate the opportunity to respond to the author's comments. We acknowledge the concerns highlighted by the author's regarding cannulation into the supra-aortic vessels through right TRA due to the angular course of the ARSA to the ascending aorta and unfavorable catheter trajectory.2,4 As mentioned, there is an increased risk of arteria lusoria dissection.2 To combat this, we recommend the guide catheter also be advanced over the diagnostic catheter to provide additional support and gentle manipulation of the catheter system, preventing excessive force, to ensure it maintains its shape and does not collapse into the aorta or kink.1,5 In addition, in our case, the prior successful navigation of our patient's aortic arch suggested that stent placement through right TRA could be performed.1 We would also like to reiterate the importance of preprocedural assessment of the neck vasculature and careful planning for each individual patient to ensure safe and effective treatment.1,5 While alternative options such as left TRA or transfemoral access (TFA) are available, each presents risks and challenges of their own. As mentioned in a case report by Majmundar et al6 published in 2020, positioning of the left wrist for left TRA and the unfamiliarity of forming the Simmons catheter from the opposite side can be difficult. However, the authors reported successful navigation in 3 cases making this a viable option. When attempting TRA, there is a risk of requiring cross-over to TFA, if TRA is not feasible. We would like to highlight that recent studies have reported high rates of technical success and low rates of cross to TFA for neuroendovascular procedures.7 TRA is increasingly being preferred over TFA because of the reduction of cost of surgery, length of hospital stay, and postprocedural patient discomfort.8 To conclude, we appreciate the opportunity to respond to the comments raised by the authors of the letter to the editor. We believe that our article provides valuable insights into the use of flow-diverting stent therapy for the treatment of complex aneurysm, even in patients harboring an ARSA. We hope that our article will stimulate further research and discussion on this important topic.