Transcatheter edge-to-edge repair for arcade-like mitral apparatus: expanding treatment options and assessing clinical outcome

Background The arcade-like mitral apparatus is a rare congenital anomaly characterized by complex subvalvular pathology, often resulting in mitral dysfunction. These anatomical complexities make conventional surgical interventions particularly challenging, especially for elderly high-risk patients. For these patients, less invasive options like Transcatheter Edge-to-Edge Repair (TEER) present a promising alternative, addressing both anatomical challenges and procedural risks. Aims To assess the feasibility, procedural success, safety, and clinical outcomes of TEER in patients with isolated severe MR due to arcade-like mitral apparatus. Methods This case series involved four high-risk patients with isolated severe mitral regurgitation (MR) secondary to arcade-like mitral apparatus treated with TEER between August 2022 and August 2023. Each patient was evaluated by a multidisciplinary Heart Team to ensure optimal selection and procedural planning. Detailed anatomical assessment using advanced imaging techniques, was performed to customize the approach and ensure procedural success. The MitraClip XTR device was employed in all cases, with careful attention to patient-specific anatomical challenges. Results TEER was successfully performed in all patients, with immediate and sustained reductions in MR severity. At the one-year follow-up, all patients demonstrated improved cardiac function, an increase in New York Heart Association (NYHA) functional class, and a reduction in Borg dyspnea scores. Significant improvements in myocardial mechanics and work parameters were observed. Global Longitudinal Strain (GLS) improved significantly compared to baseline. The Global Work Index (GWI), Global Constructive Work (GCW), Global Pressure-Volume Work (GPW), Global Systolic Constructive Work (GSCW) and Global Work Efficiency (GWE) also showed a marked increase. Conclusion TEER represents a promising, minimally invasive option for managing severe MR due to arcade-like mitral apparatus in high-risk patients. This case series underscores TEER's potential to offer significant symptom relief and improved hemodynamics, presenting a new therapeutic perspective for treating isolated MR in this anatomically challenging condition. Further large-scale studies are warranted to validate these findings and establish TEER's role in broader clinical practice.