The pivotal role of cardiac computed tomography angiogram and (18)F-fluorodeoxyglucose positron emission tomography-computed tomography in the diagnosis of right sided endocarditis: a case report

BACKGROUND: Infective endocarditis (IE) poses many clinical and diagnostic challenges. Echocardiography is regarded as the imaging modality of choice for the diagnosis of IE, and plays a key role in both the diagnosis and management of endocarditis. We report on a case in which one could have overlooked an endocarditis of a pulmonary homograft if one had relied on echocardiography alone. CASE SUMMARY: A 38-year-old man presented with intermittent fever and fatigue for 1 month. He had undergone a Ross procedure for a bicuspid aortic valve stenosis at the age of 17 years. At the age of 36 years a valve-sparing aortic root replacement was performed because of aortic root dilatation. Besides a systolic murmur 3/6 noted at the left sternal border, physical examination was normal. Multiple blood cultures grew Streptococcus mitis. Both transthoracic and transoesophageal echocardiogram could not detect any signs of endocarditis. As endocarditis can be overlooked due to reverberations and acoustic shadowing, we performed (18)F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG-PET/CT) and cardiac computed tomography angiogram (cardiac CTA). Both imaging modalities showed large vegetations attached to the pulmonary homograft. DISCUSSION: Endocarditis poses diagnostic challenges. While echocardiography is the cornerstone of imaging, one may overlook a pulmonary homograft endocarditis due to reverberations and acoustic shadowing. Therefore, if clinical suspicion of endocarditis is strong, one should consider additional imaging by means of cardiac CTA and/or (18)F-fluorodeoxyglucose positron emission tomography-computed tomography imaging to assess valves in pulmonary position, especially in those whom have had prior surgical intervention at this location.