Resolution of thrombus in left ventricular outflow tract pseudoaneurysm mimicking periaortic abscess

Prosthetic valve complications are not uncommon after valve replacement. In this paper we report a female patient who presented with aortic prosthetic valve endocarditis and echocardiographic appearance of periaortic abscess. After 6 weeks of antibiotic therapy, echocardiographic examination revealed resolution of abscess cavity and replacement with a clear blood-filled anechoic sac. Diagnosis was made by cardiac computed tomography, which showed a left ventricular outflow tract (LVOT) pseudoaneurysm rather than an abscess, located just below the sewing ring of the prosthetic aortic valve. We assumed that either resolution of thrombus in LVOT pseudoaneurysm following effective warfarin therapy or clearance of infective content in pseudoaneurysm after co-administered antibiotics gave rise to change in echocardiographic characteristics in the perivalvular area.