Endocarditis and Incomplete Endothelialization 12 Years after Amplatzer Septal Occluder Deployment

Abstract

A 4-year-old boy had a 15-mm atrial septal defect repaired percutaneously with use of an Amplatzer Septal Occluder. At age 16 years, he presented with a week's history of fever, chills, dyspnea, fatigue, and malaise. Cultures grew methicillin-sensitive Staphylococcus aureus. A transesophageal echocardiogram showed a 1.25 × 1.5-cm pedunculated mass on the left aspect of the atrial septum just superior to the mitral valve, and a smaller vegetation on the right inferior medial aspect of the septum. At surgery, visual examination of both sides of the septum revealed granulation tissue, the pedunculated mass, the small vegetation, and exposed metal wires that suggested incomplete endothelialization of the occluder. We removed the occluder and patched the septal defect. The patient returned to full activity after 4 months and was asymptomatic 3 years postoperatively. Our report reinforces the need for further investigation into prosthetic device endothelialization, endocarditis prophylaxis, and recommended levels of physical activity in patients whose devices might be incompletely endothelialized. In addition to reporting our patient's case, we review the medical literature on this topic.

Keywords: Biocompatible materials/metabolism; cardiac catheterization/instrumentation; endocarditis, bacterial/etiology/pathology/prevention & control; endothelial cells/metabolism; heart defects, congenital/therapy; heart valve prosthesis implantation/adverse effects/instrumentation/methods; prosthesis-related infections/etiology/therapy; septal occluder device/adverse effects; time factors; treatment failure.

Fig. 1

Transesophageal echocardiogram shows a pedunculated mass (arrow) superior to the mitral valve. AS = atrial septum; LA = left atrium; LV = left ventricle; MV = mitral valve

Fig. 2

Intraoperative photograph of the right septum shows an incompletely endothelialized Amplatzer Septal Occluder (arrow) and vegetation on its inferior medial border (arrowhead).

Fig. 3

Intraoperative photograph of the left atrium (LA) shows the atrial septum and the Amplatzer Septal Occluder (ASO) retracted superiorly. The ASO's left disc is poorly endothelialized (arrow), and a pedunculated mass is visible above the mitral valve (arrowhead).