Abstract 2136: Increased risk of Infective Endocarditis in adults with Tetralogy of Fallot and Bicuspid Aortic Valve disease
Background: The new infective endocarditis (IE) guidelines of the British Society for Antimicrobial Chemotherapy (BSAC) 2006 and AHA 2007 state that the only high risk cardiac factors requiring dental prophylaxis are previous IE, prosthetic cardiac valves/surgically created shunts or conduits, unrepaired cyanotic congenital heart disease patients (CHD), or repaired CHD with residual defects. We performed a retrospective analysis of the Ahmanson/UCLA Adult Congenital Heart Disease registry to assess prevalence, anatomy, interventions, and outcomes of IE to determine those at highest risk.
Results: Of 2,842 adults in the registry, 135 pts (70 male & 65 female, median age 28 yrs at time of diagnosis) had 157 episodes of IE (157/2842, 6%). Tetralogy of Fallot (TOF) accounted for 23%, bicuspid aortic valve (BAV) 17%, ventricular septal defect 14%, “single ventricle” physiology 14%, TGA physiology 8%, & double outlet right ventricle 6%. Native valves affected were aortic 46%, mitral 12%, tricuspid 10%, and pulmonic 4%; prosthetic valves/conduits or palliative shunts 17%. Organisms were documented in 54 episodes; Streptococcus Viridans (37%) & Staphylococcus Aureus (7%) predominated. Of 242 TOF pts: there were 37 IE episodes, 31 had sufficient data (44% of identifiable locations were aortic valve, 22% prosthetic conduits, 6% tricuspid valve, 6% mitral valve); median age at diagnosis = 24 yrs, 1:3 male-to-female ratio; 76% had previous cardiac surgery remote from the episode; there was 1 acute (within 6 weeks) death and 3 pts required acute surgery. Of 271 BAV pts: there were 26 episodes of IE (81% on native aortic valves, 15% on aortic valve prostheses), 27% had prior valvuloplasty; median age at IE diagnosis =32 yrs, 9:4 male-to-female ratio; there were no acute deaths; 4 cases required acute surgery.
Conclusions: Certain substrates of CHD are known to increase the risk for IE. TOF represents the largest proportion of IE cases in our center, followed next by BAV. Repaired TOF often has residual aortic regurgitation - a substrate for aortic valve IE. In contrast to new AHA and BSAC guidelines, we demonstrate that BAV and operated TOF constitute a high-risk for IE.