Role of PET Imaging in Detection and Management of Arrhythmias

1365 Objectives: Cardiovascular imaging plays an important role in the detection and management of arrhythmias. The last two decades have consisted of significant advances which have allowed for the transition of the commonly used echocardiographic techniques to more precise imaging modalities such as PET that can identify the arrhythmic foci. Moreover, the utility of PET in cardiac imaging has evolved from a simple diagnostic role to a more complex role that is capable of guiding ablation procedures in arrhythmias such as ventricular tachycardia (VT) that is seen with many inflammatory cardiomyopathies. The pathophysiology of arrhythmias is a complex process that results from an interplay between myocardial triggers and anatomical substrates which leads to a disruption in the electrical circuit of the heart. Of the various etiologies, the most frequent causes that predispose an individual to an arrhythmia are cardiomyopathies. Cardiac sarcoidosis (CS) is a specific type of cardiomyopathy classified by granulomas of white blood cells in myocardium and often results in VT. PET imaging has the potential to detect inflammatory foci in the heart in CS, namely through the use of radiotracers such as FDG. CS can form scar tissue which acts as a nidus for re-entrant arrhythmias, allowing FDG-PET to identify the non-viable tissue so appropriate intervention can be taken. Due to the increasing occurrence of arrhythmias, there has been a transition to PET and hybrid imaging (PET/MRI and PET/CT) in guiding electrophysiologic ablation procedures. Whereas FDG-PET provides metabolic information, MRI/CT imaging allows for understanding of the morphologic information. Though recent studies have leveraged late gadolinium enhancement in MRI in addition to inflammation in FDG-PET/CT scans, there lacks exploration of FDG-PET/MRI assessment of CS, which can present a more accurate diagnosis as they specifically target the arrhythmogenic foci in cardiac sarcoidosis. In this exhibit, we will review the following: 1) FDG-PET in cardiac sarcoidosis, 2) Radiotracers used in conjunction with PET to detect arrhythmias, 3) Pathophysiology of arrhythmias in cardiac sarcoidosis, 4) Role of PET in guiding ablation therapy 5) Role of PET in assessing myocardial ablation response in arrhythmias