Multiple clips for transcatheter mitral valve repair in failing Fontan

A 32-year-old male with pulmonary atresia/intact ventricular septum, underwent a right Blalock–Thomas–Taussig shunt (age 5 months), bidirectional Glenn operation (age 1 year), Fontan operation with intracardiac tunnel (age 3 years), and subsequently with lateral tunnel (age 4 years). He developed severe mitral regurgitation (MR, red arrow) leading to numerous admissions for heart failure. Functional class was NYHAIII. Pre-operative imaging (see Supplementary data online, Videos S1–S3) showed that the MR (regurgitant fraction = 60%) was mainly due to A2 prolapse (white arrow) (flail gap = 9 mm). The round-shaped annulus measured 60 mm. The single ventricle was dilated (iEDV 143 mL/m2) with preserved fraction. Surgical risk was deemed too high, and the patient was elected to transcatheter edge-to-edge repair. Via a 12 Fr right femoral vein access, the single atrium was reached via trans-tunnel puncture using standard trans-septal needle post-dilated with a 10 × 20 mm high-pressure balloon under transoesophageal echocardiogram and fluoroscopic guide. Advanced steering manoeuvres to obtain device coaxiality were performed, as the tendency was ‘aortic hugging’ due to expected (based on CT and 3D-printed model) conduit misalignment to the annular plane. A first XTW Mitraclip G4 (Abbott Vascular, Menlo Park, CA, USA) was positioned between A2-P2 scallops with residual moderate MR. A second XTW device was implanted to stabilize the first clip. The remaining lateral leak was due to lateral A2 prolapse and concomitant P1-P2 deep indentation; hence, a third XTW device using non-standard manoeuvres (significant clockwise rotation to connect the medial P1 portion to the residual A2 prolapse, green arrows) was implanted. This asymmetric implant was guided on an ad hoc four-chamber view depicting A2-P1 and the clip arms. Final MR was trivial (yellow arrow; Supplementary data online, Videos S4–S7), without stenosis.