Building Up the Diagnosis of Cardiac Device Infections: The Role of Imaging

Among the complications of cardiac implantable electronic devices (CIED), infections represent one of the nastiest in view of the heavy impact on clinical outcomes and associated costs for healthcare systems. CIED-related infections (CIEDI) can present with several different clinical manifestations increasing the complexity of the diagnostic process. Clinical examination, laboratory exams, blood cultures, and swabs all are mandatory steps for the diagnostic process, similarly to what occurs during diagnosis of endocarditis. However, since signs and symptom may be mild or confusing, imaging has a key role in providing the correct diagnosis. In the present chapter we will discuss the various aspects of echocardiography (transthoracic, transesophageal, and intracardiac) in ruling out CIEDI diagnosis. Later we will discuss the role of computer tomography and magnetic resonance in view of their increasing use in the management of endocarditis, focusing on their pros and cons in the CIEDI setting. Finally, we will focus on nuclear imaging discussing all the various aspects of 18F-FDG PET scan and white blood cell SPET for diagnosis of CIEDI elucidating the advantages among the other imaging techniques but also clarifying how to obtain the maximum from these tools. Notably, the role of imaging techniques is not limited to help defining the diagnosis of CIEDI. For this reason we will dedicate a large part of this chapter to discuss their role in assessment of the extension of the infectious process, detection of complications, supporting transvenous lead extraction (TLE) procedures, planning CIED reimplantation, and helping in predicting post-TLE risk of reinfection or death.