Abstract 14148: Left Ventricular Outflow Tract Pseudoaneurysm in a Pediatric Patient: An Unusual Presentation of Endocarditis

Abstract

Description of Case: A 12-year-old male with known bicuspid aortic valve presented with one month of progressive weight loss and subjective fevers. Transthoracic echocardiogram was concerning for a new left ventricular outflow tract (LVOT) aneurysm (figure 1). His aortic valve stenosis and regurgitation had notably progressed compared to a prior study one year ago. He was urgently referred for cardiac computed tomographic angiography (CCTA), which demonstrated a pseudoaneurysm of the LVOT inferior to the aortic valve and irregularly thickened aortic valve leaflets with a notable perforation (figure 2). Blood cultures were positive for Viridans streptococci, confirming the diagnosis of infective endocarditis. The patient was referred for a Bentall procedure with LVOT pseudoaneurysm repair. Pre-operative transesophageal echocardiogram demonstrated a communication of the non-coronary cusp of the aortic valve and LVOT. Ultimately, aortic root replacement was performed with a 23mm homograft. Our patient recovered well from surgery and now has excellent clinical status with normal aortic valve function. Discussion: Pseudoaneurysm of the LVOT as a result of infective endocarditis is a rare diagnosis, especially in the pediatric population. Of the case reports published, it is most seen in the setting of infection involving the native aortic valve but has also been reported after aortic valve replacement. As in our patient, the most commonly reported location involves the mitral-aortic intervalvular fossa. Symptoms have insidious onset and the diagnosis requires a high level of suspicion. A multimodal imaging approach is warranted for optimal diagnosis and treatment.