Abstract 12657: Congenital Pseudoaneurysm of the Mitral-Aortic Intervalvular Fibrosa: A Case Report
Introduction: The mitral-aortic intervalvular fibrosa (MAIVF) is the area of fibrous continuity between the mitral and aortic valves. Pseudoaneurysm formation can rarely occur here after trauma, commonly surgical or infectious. We describe the first case of a congenital pseudoaneurysm of the MAIVF (PMAIVF) seen prenatally as an isolated cardiac defect and followed conservatively postnatally.
Case Report: A fetal echocardiogram was performed at 30 weeks gestation after an echogenic cardiac focus was seen on fetal ultrasound. A large left atrial mass with mixed echogenicity was seen oriented along the atrial septum with suggestion of flow in the lesion on color Doppler (Fig 1A-B). The mass was not obstructing mitral, aortic or foramen ovale flow and the rest of the cardiac anatomy was normal. A comparative view on the postnatal echocardiogram confirmed the presence of an echolucent mass with flow into the lesion on color Doppler (Fig 1C-D). The parasternal long axis demonstrated the neck of the aneurysm arising between the mitral and aortic annuli with lack of fibrous continuity (Fig 2A). Color Doppler demonstrated blood flow into the pouch during systole and into the left ventricular outflow tract during diastole consistent with a congenital PMAIVF (Fig 2B-C). Pulsed-Doppler showed antegrade and retrograde flow in the neck (Fig 2D). The infant is now 4 months old and serial echocardiograms have shown stable size and appearance of the PMAIVF, with low velocity bidirectional flow into the neck, and it has remained non-obstructive.
Conclusion: PMAIVF can exist without preceding trauma as a rare, isolated congenital cardiac defect. The natural history of a congenital PMAIVF is unclear.
Author Disclosures: J.K. Harrington: None. J. Glickstein: None. A. Shah: None.
- © 2016 by American Heart Association, Inc.