Pulmonary Valve Endocarditis: The Potential Utility of Multimodal Imaging Prior to Surgery

Background: The presence of echocardiographic (echo) evidence is a major criterion for the diagnosis of infective endocarditis (IE) by modified Duke criteria. Pulmonary valve (PV) IE, however, can be challenging to identify by echo. We sought to evaluate the added utility of multimodal imaging in PV IE. Methods: This is a single-center case series. We retrospectively analyzed demographic, laboratory, imaging, clinical, and surgical data from patients diagnosed with PV IE from 2008 to 2018. Results: A total of 23 patients were identified with definite PV IE by Duke criteria (83% male and ages 2 months to 70 years). Twenty-two patients had congenital heart disease, with 21 involving the right ventricular outflow tract (including three with transcatheter PV implant). Overall, 20 (87%) of 23 had positive blood cultures. A total of 17 (74%) of 23 patients demonstrated echo evidence of PV IE. In three cases, echo was negative (did not show vegetations) but showed new PV obstruction. In four cases with negative transthoracic echocardiogram and transesophageal echocardiogram, evidence of PV IE was subsequently seen by positron emission tomography/computed tomography (n = 2) or cardiac magnetic resonance imaging (n = 2). Pulmonary valve IE was confirmed at surgery by evaluation of pathologic samples in 20 cases. Conclusions: Multimodal imaging improves the ability to preoperatively identify endocardial involvement in PV IE in cases where echo is negative. Consideration should be given to revise Duke criteria to include new obstruction and endocardial involvement by multimodal imaging for PV IE.