Cath Lab Digest

Abstract

Paravalvular leak (PVL) is a relatively uncommon but potentially serious complication of surgical mitral valve replacement (MVR). In the presence of symptoms, surgical repair of PVL is recommended to prevent consequences such as heart failure, endocarditis and hemolysis. Reoperation, however, has been associated with an increased likelihood of recurrent leak and significant morbidity and mortality, thereby rendering percutaneous transcatheter closure of PVL an increasingly attractive alternative. We describe a case of successful transcatheter closure of a mitral paravalvular leak utilizing an Amplatzer muscular VSD occluder device, guided by 3D-echocardiography.

Case

A 51-year-old male presented with symptoms of progressively worsening dyspnea on exertion over one year. His history was significant for mitral valve annuloplasty approximately six years prior, complicated by valve ring dehiscence and subsequent valve replacement within one year of the initial operation. His current presentation prompted evaluation with stress echocardiography, which revealed diminished exercise capacity with mitral PVL. The patient subsequently underwent transesophageal echocardiography (TEE), confirming the presence of at least moderate paravalvular regurgitation originating from the posterior aspect of the mitral annulus (Figure 1). Given these findings and the relatively high risk of reoperation in the setting of multiple prior sternotomies, percutaneous transcatheter closure of the PVL was recommended. 

The patient was taken to the cardiac catheterization laboratory and both femoral arterial and venous access obtained. Transseptal puncture was achieved utilizing a transseptal sheath and a Brockenbrough needle, and position within the left atrium confirmed using contrast injection, pressure measurement, and oxygen saturation. The PVL was then crossed with a stiff angled Glidewire (Terumo) (Figure 2), followed by advancement of an IM diagnostic catheter (Cordis) into the left ventricle. The Glidewire was then exchanged for an Amplatz stiff wire (Cook Medical) and a 7-French Pinnacle destination sheath (Terumo) advanced through the defect. A 6-mm Amplatzer muscular VSD occluder (AGA Medical) was then prepped and deployed across the PVL (Figure 3). Intraoperative transesophageal echocardiogram (TEE) visualized the device as seated properly across the defect with no significant motion or residual regurgitation (Figure 4).  Additional fluoroscopic views also confirmed that the device was not impinging upon the mechanical valve leaflets (Figure 5). 

Three months post-procedure, the patient returned to clinic for follow-up and reported significant improvement in symptoms. Repeat transthoracic echocardiogram correlated aptly with no significant mitral valvular insufficiency.

Discussion

PVL following surgical MVR occurs when a complete seal between the prosthesis and the surrounding tissue is not achieved. PVL resulting in serious clinical sequelae occur in up to 5% of patients who have undergone surgical valve replacement.¹ Repeat surgery has typically been recommended as the first choice to correct the problem and prevent serious complications such as heart failure, endocarditis and hemolysis. Reoperation, however, has been associated with mortality rates as high as 16% and an increased risk for recurrent leaks compared to the initial procedure.² For this reason, transcatheter mitral PVL closure has become an increasingly attractive option.

The reported success rate of transcatheter mitral PVL closure has been variable, ranging from 60% to 90%, with a need for repeat intervention in up to 40% of cases.¹ In addition to the technically challenging nature of the procedure, the variable success rates have also been attributed to the lack of a purpose-specific occluder device, as well as the limitations of available imaging modalities in accurately defining the three-dimensional anatomy and spatial orientation of the paravalvular defect.^3,4

To date, there are no devices approved by the U.S. Food and Drug administration (FDA) for the specific purpose of PVL closure. This has resulted in the off-label use of various other devices that have been approved by the FDA for the closure of other cardiovascular defects such as atrial septal defects, patent foramen ovale, and ventricular septal defects. More recently, specific PVL occluder devices are being developed with the hope that their designed geometries will allow for less interference with the surrounding valve leaflets than other currently available occluders.⁴