Balloon-expandable Myval valve-in-valve transcatheter aortic valve implantation with bailout left main coronary artery chimney stenting: a case report.

Background: Transcatheter aortic valve implantation-in-transcatheter aortic valve implantation represents a progressive solution for patients with degenerated transcatheter heart valves, especially those at high surgical risk. With the increasing use of transcatheter aortic valve implantation worldwide, the need for redo procedures is also rising. Balloon-expandable valves such as the Myval transcatheter heart valve (Meril Life Sciences Pvt. Ltd.) offer design advantages of enhanced radial strength, low-profile frames, and effective sealing, making them suitable for complex valve-in-valve scenarios. An essential procedural concern in redo transcatheter aortic valve implantation is the risk of coronary obstruction, particularly involving the left main coronary artery, requiring pre-emptive planning strategies such as the chimney technique.

Case presentation: We report the case of a 68-year-old female patient of Indian ethnicity with prior transcatheter aortic valve implantation using a 26 mm CoreValve (Medtronic), presenting with symptomatic valve degeneration. Her case having been deemed high-risk for open surgical intervention, she was selected for a transcatheter aortic valve implantation-in-transcatheter aortic valve implantation procedure. Preprocedural computed tomography imaging showed a critical risk plane for the left main coronary artery, necessitating coronary protection. A 23 mm balloon-expandable Myval transcatheter heart valve was implanted using transfemoral access. Coronary protection was initiated with prepositioning of a coronary guidewire in the left coronary artery. Following valve deployment, the patient developed hypotension with left main coronary artery flow compromise, requiring bailout left main coronary artery stenting, resulting in a chimney configuration. Postdeployment angiography confirmed optimal valve positioning with preserved coronary flow. The patient initially developed hypotension and severe hypokinesia, which was managed successfully with emergency left main coronary artery stenting and supportive care. She exhibited immediate hemodynamic recovery and was discharged in a stable condition. This is the first documented case of a Myval-based transcatheter aortic valve implantation-in-transcatheter aortic valve implantation with left main coronary artery chimney stenting from East India.

Conclusion: This case highlights the feasibility, safety, and procedural effectiveness of the Myval balloon-expandable transcatheter heart valve in a redo transcatheter aortic valve implantation setting. It also underscores the importance of anatomical evaluation, risk stratification, and pre-emptive coronary protection in complex structural heart interventions. The successful use of the chimney technique reinforces its role in mitigating life-threatening coronary occlusion during valve-in-valve procedures. This report contributes to the growing evidence supporting the use of next-generation transcatheter heart valves for complex redo transcatheter aortic valve implantation scenarios and expands the clinical applicability of Myval in high-risk cases.