Intermittent acute aortic regurgitation of a mechanical bileaflet aortic valve prosthesis: diagnosis and clinical implications.

Intermittent aortic regurgitation (AR) is an unusual complication after a mechanical prosthetic replacement. We describe a rare case of intermittent dysfunction of a bileaflet mechanical aortic prosthetic valve in a 41-year-old man with a 21 mm Tri-technologies prosthetic valve implanted 4 years before. Transthoracic echocardiography (TTE) before discharge was normal and prosthesis-patient mismatch was ruled out. He was admitted to our hospital because of mild dyspnoea at effort. TTE revealed acute and severe intermittent AR. The patient underwent surgery, during which abnormal proliferation of subvalvular pannus overgrowth on the inflow aspect of the prosthesis was found impeding the normal closure of one of the discs of the prosthesis. The pannus formation was resected, the Tri-technologies prosthetic valve was prophylactic explanted and a 23 mm St Jude Medical bileaflet mechanical prosthesis valve was implanted. We describe the role of TTE and the limitation of the cinefluoroscopy in the diagnosis of Tri-technologies prosthetic dysfunction.