157 Stentless Aortic Valve bioprosthesis Dehiscence – A Possible Infective Endocarditis with Atypical Presentation but Serious Consequences

Abstract

We recently reported an atypical possible prosthetic valve infective endocarditis (PVIE) occurring on a stentless Cryolife O’Brien ® aortic bioprosthesis without inflammatory markers, negative blood cultures but anatomic damage suggestive of IE and aimed to look for other cases. We reviewed all cases of possible or definite aortic PVIE according to the modified Duke criteria hospitalized in our institution between January 2002 and March 2008. 60 patients with possible or definite aortic PVIE were admitted during this period (26 mechanical prosthesis, 11 stented bioprosthesis and 23 stentless Cryo-Life O’Brien ® bioprosthesis). Compared to mechanical or stented prosthesis, patients with stentless valve presented less frequently with fever (39% vs. 77% and 91%, p=0.003), tended to present more frequently in congestive heart failure (54% vs. 23% and 36%, p=0.10), less frequently with positive blood cultures (44% vs. 65% and 82%, p=0.08) and with lower CRP levels (69±70 mg/L vs. 144±106 mg/L and 145±123 mg/L, p=0.02). Patients with stentless valve also presented less frequently with vegetations (22% vs. 58% and 63%, p=0.01) but more frequently with valve dehiscence (68% vs. 23% and 22%, p=0.006) and severe aortic regurgitation (65% vs. 23% and 36%, p=0.01). 40 patients were operated on within 30 days, more frequently in the stentless group (83% vs. 61% and 45% respectively, p=0.07). Compared to the previously reported incidence of stentless PVIE at our institution (1.5%), we observed a striking increase incidence after 2004 (>7%). We report a frequent and atypical clinical and microbiological presentation of possible PVIE occurring on stentless bioprosthesis and a striking increased incidence after 2004 which corresponds to changes in the manufacturing process. Clinicians should be aware of this atypical clinical presentation. The stentless Cryo-Life O’Brien ® bioprosthesis is not anymore implanted at our institution.