Prosthetic pulmonary valve and pulmonary conduit endocarditis: clinical, microbiological and echocardiographic features in adults

Aims To review clinical and microbiological findings in adults with prosthetic pulmonary valve (PPV) or right ventricle to pulmonary artery conduit (RVPAC) infective endocarditis (IE) and to assess the yield of transthoracic (TTE) and transesophageal echocardiography (TEE) as diagnostic tools. Methods and results Seventeen adults (age >= 18 years) with PPV/RVPAC who met diagnostic criteria for definite IE between 2000 and 2015 were included. Median age was 34 years and 29% were females; four patients (24%) had a previous episode of IE. IE occurred a median interval of 5.3 years after PPV/RVPAC insertion; median follow-up time was 206 days. The most common organisms were Staphylococcus aureus (29%), coagulase-negative staphylococci (24%), and streptococcal species (24%). Eleven patients (64.5%) required PPV/RVPAC replacement surgery as consequence of the IE episode. There were three deaths during follow-up; one non-operative and two post-operative. TTE was diagnostic for PPV/RVPAC IE in 10 (62%) and TEE was diagnostic in eight (57%) patients; when combined TTE/TEE were diagnostic in 15 of 17 (88%) cases. Severe PPV/RVPAC obstruction was present at the time of IE diagnosis in nine (53%) and severe regurgitation in five (29%). Conclusion PPV/RVPAC IE is associated with significant morbidity, mortality and high risk of requiring operative intervention. TTE and TEE are marginal diagnostic tools when used independently; they should be used as complementary techniques in the evaluation of those patients. Severe PPV/RVPAC stenosis was more common than regurgitation in patients with IE; thus IE should be considered in patients presenting with new PPV/RVPAC obstruction.