In this case we describe a 68-year-old male patient who presented with malaise after being treated for a urinary tract infection caused by enterococcus faecalis. The electrocardiogram showed atrial fibrillation and subsequent transthoracic echocardiography revealed a mobile structure on the pulmonary valve with an increased transpulmonary valve gradient (Fig. 1). Blood cultures were positive for enterococcus faecalis and PET-CT revealed F‑18-fluorodeoxyglucose (FDG) uptake in the right ventricular outflow tract and lungs.

Fig. 1
figure 1

TTE showing a mobile structure on the pulmonary valve. TT transthoracic echocardiography

Transoesophageal echocardiography revealed a previously unknown small atrial septal defect type 2 with left-to-right shunt as well as a moderate pulmonary valve stenosis and severe regurgitation (Fig. 2).

Fig. 2
figure 2

TEE showing thickened pulmonary valve and atrial septal defect. TEE transoesophageal echocardiography

In the majority of cases, right-sided infective endocarditis involves the tricuspid valve and is associated with intravenous drug use or the presence of pacemakers [1,2,3]. In this case, a type 2 atrial septal defect and a dysplastic pulmonary valve were observed. This case underscores the importance of thorough investigation of coexistent congenital heart defects in cases of right-sided infective endocarditis [4].