Leaflet tear or what? A challenging echocardiographic diagnosis after percutaneous mitral valve edge-to-edge repair

Abstract

A 60-year-old male with ischemic cardiomyopathy was hospitalized due to progressive congestive heart failure. Symptom improved from NYHA4 to NYHA3a, but severe functional mitral regurgitation (MR) remained despite optimal medical therapy. Considering the comorbidity such as chronic kidney disease and severely reduced left ventricular ejection fraction (25%), he underwent percutaneous mitral valve edge-to-edge repair using MitraClip® and discharged with stable condition. 1 month after the procedure, congestive heart failure suddenly developed with recurrent severe MR. Transesophageal echocardiography (TEE) revealed the MitraClip® detachment from the posterior leaflet, but a bridge-like tissue from the posterior leaflet still connected to the device (Fig. 1a, yellow arrow), which implied posterior leaflet tear (Fig. 1a). Regurgitant jet mainly originated from the tear-like portion (Fig. 1b and d). 3D echocardiography confirmed the connection between the posterior leaflet and the devise (Fig. 1c). Redo-transcatheter intervention was proposed as a less-invasive strategy for this patient with severe LV dysfunction, but the Heart-Valve team discussion finally decided surgical repair for this patient considering the possibility of leaflet damage. Operative finding revealed no leaflet tear but a marginal chorda entrapped in the MitraClip® (Fig. 1e, yellow arrow), and the diagnosis of single leaflet device attachment (SLDA) was confirmed (Fig. 1e and f). SLDA is defined as the complete loss of connection between a clip and one leaflet [1]. If parts of the leaflet tip disconnected with the edge of the MitraClip® and did not unattached completely from the edge of the MitraClip® at diastole, leaflet tear is diagnosed [2]. In this case, the TEE findings showed a bridge-like tissue connecting the tip of posterior leaflet and the MitraClip® which mimicked leaflet tear. In detail 3D observation should be a key to distinguish the current findings were SLDA or leaflet tear, and it is important to identify the discontinuation of the leaflet to diagnose leaflet tear. In this case, identifying the discontinuation of the posterior leaflet was a big challenge due to the artifact related to the clip device. At least, the bridge-like tissue connected the device and posterior leaflet could be assumed as a torn posterior leaflet as well as a subvalvular chorda, and hence, we decided to choose a surgical strategy considering in case of leaflet tear. The bridge-like structure was actually a chorda as shown in the intraoperative findings. 3D images often overestimate tissue thickness because of its relatively low spatial resolution and we recognized the thin chordae as a thicker structure than it actually was.