Cleft-directed transcatheter edge-to-edge repair of an isolated anterior mitral leaflet cleft

A 55-year-old man presented with exertional dyspnoea and orthopnoea. Eight years earlier, an isolated anterior mitral leaflet cleft with moderate mitral regurgitation (MR; jet area 5.1 cm2) had been diagnosed. Serial echocardiography documented progression to severe MR (vena contracta 8.1 mm, effective regurgitant orifice area 0.88 cm2, regurgitant volume 151 mL), with left atrial enlargement to 56 mm. The patient declined surgery and underwent transcatheter edge-to-edge repair (TEER) with the DragonFly system. Three-dimensional transoesophageal echocardiography demonstrated a broad A1-A2 cleft (area = 0.60 cm2) with MR originating from the cleft (Panels A and B; Supplementary Movies S1 and S2). A single short-wide clip was selected to bridge the cleft while minimizing traction on the anterior leaflet and providing adequate coverage of the broad defect. Initial grasping at the medial aspect of the cleft reduced the cleft area to 0.13 cm2 but left residual eccentric MR lateral to the clip (Panels C and D; Supplementary Movies S3–S5). Under real-time three-dimensional transoesophageal echocardiographic guidance, the clip was reopened and repositioned towards the cleft margin, achieving complete cleft closure and reducing MR to mild, with a post-procedural mitral valve area of 6.24 cm2 (Panels E and F; Supplementary Movies S6–S8).