Application of Real-Time 3-Dimensional Transesophageal Echocardiography in the Percutaneous Closure of a Mitral Paravalvular Leak

Abstract

A 51-year-old man presented to our hospital with increasing shortness of breath and lower extremity edema. He was status post St. Jude mechanical mitral valve replacement for endocarditis 4 years before admission. Transesophageal echocardiography (TEE) revealed a severe paravalvular leak around the inferolateral aspect of the sewing ring. Left ventricular systolic function was reduced (ejection fraction of 35%–45%). His mean diastolic pressure gradient across the mitral valve was 6 mm Hg. A small secundum atrial septal defect (ASD) with bidirectional shunting was observed. The patient was referred for percutaneous closure of the paravalvular leak with an Amplatzer occluder. TEE was used to help guide the catheter-based procedure. Real-time 3-dimensional (RT3D) TEE (X7-2t transducer, Philips Healthcare, Andover, MA) was used to create color full-volume gated reconstructions demonstrating a severe inferolateral crescentic paravalvular leak (Fig. 1). (Video 1, see Supplemental Digital Content 1, http://links.lww.com/AA/A112. See Appendix for Video captions.) The feasibility of closure with placement of a circular device on a curvilinear defect was discussed, but the decision was made to proceed. Initially, an 8-mm Amplatzer Septal occluder (AGA Medical, Plymouth, MN) was deployed across the paravalvular defect using RT3D TEE as an aid to catheter navigation (Fig. 2). With 2D color flow Doppler (CFD) interrogation, the leak was unchanged so that the occluder was extracted and a larger 12-mm device was deployed. Repeat 2D CFD, despite the presence of acoustic shadowing artifact along the path of regurgitation, suggested a severe persistent leak on the basis of vena contracta width (6.9 mm). (Video 2, see Supplemental Digital Content 2, http://links.lww.com/AA/A113. See Appendix for Video captions.) An RT3D “en face” view of the mitral valve confirmed the severity of the leak and the inability of the circular Amplatzer to span the curvilinear defect (Fig. 3). (Video 3, see Supplemental Digital Content 3, http://links.lww.com/AA/A114. See Appendix for Video captions.) The procedure was terminated and the Amplatzer left in place. The patient’s symptoms were not improved, and he was referred for operative intervention. He underwent a successful redo-sternotomy, explantation of a normal-appearing Amplatzer device, primary closure of the inferolateral paravalvular defect, and ASD closure. Three weeks after his operation, he was seen in follow-up and was asymptomatic. Amplatzer occluders are routinely used for percutaneous closure of ASDs under fluoroscopy. Although percutaneous paravalvular leak closure with Amplatzer occluders is a suitable option for patients with increased perioperative risk, beneficial outcomes have not been consistently reported. Two-dimensional TEE has been shown to complement fluoroscopy for catheter-based procedures, but there are technical limitations. The success of the procedure may depend on the ability of 2D TEE to accurately identify the location and extent of the leak. The addition of RT3D TEE offers unique advantages, which can facilitate the technical procedure and improve appropriate patient selection before the intervention. Two-dimensional TEE is not ideal for visualizing an intracardiac catheter. Locating the catheter tip within surrounding anatomic structures is difficult and requires multiple imaging planes. Minor adjustments of the wire can alter the curvature of the catheter and shift the tip outside the plane of a 2D TEE sector. Each adjustment of the catheter requires reassessment with subtle manipulations of the TEE probe to reconfirm its location within intracardiac structures. This can slow the procedure and impair communication with an interventionalist who may be less familiar with nonstandard TEE views, causing them to rely more heavily on fluoroscopy for navigation, increasing overall radiation exposure. RT3D TEE permits complete visualization of the catheter within a familiar anatomic landscape facilitating communication with the operator. Enhanced ability of catheter navigation and unequivocal confirmation of the defect location may improve overall success rates. For multiple defects in close proximity, RT3D TEE can confirm that the catheter passes through the targeted orifice before deployment of the device. RT3D TEE allows for unique perspectives that may improve patient selection for percutaneous paravalvular leak closure and other catheter-based procedures. Dehiscence of the convex sewing ring from the annulus often renders a defect crescent shaped. The extent of dehiscence can be assessed using multiple 2D imaging planes through mental reconstruction. RT3D TEE can generate an anatomic en face view of the mitral valve dehiscence, which may simplify interrogation and improve diagnostic accuracy. The extent of dehiscence can guide patient selection in cases of geometric mismatch between crescentic paravalvular defects and circular Amplatzer occluders. Deployment in such a case as ours may fail to abolish the leak and can even From the *Department of Anesthesiology, Emory University School of Medicine, Atlanta, Georgia; and †Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women’s Hospital, Boston, Massachusetts.