Cardiac sarcoid

Cardiac sarcoid (CS) is an underdiagnosed, potentially fatal condition that presents with a wide range of clinical manifestations including conduction abnormalities, tachyarrhythmias, congestive heart failure, cardiomyopathy, and sudden cardiac death. Small observational registries and non-comparative studies have described clinical evidence of cardiac involvement in 5% of patients with systemic sarcoid, yet autopsy studies suggest a prevalence as high as 70%.[1-6]. This suggests that cardiac sarcoidosis is underdiagnosed in everyday clinical practice. One explanation for this is a lack of consensus on the most appropriate methods for detecting, monitoring and treating cardiac involvement in sarcoidosis.

It has been suggested that newer imaging modalities (PET and CMR) may have important utility in guiding therapy of CS. FDG PET and MRI maybe able to detect the early and potentially reversible stages of CS.
Patients present in 3 ways: A) unexplained, new onset, conduction system disease. B) idiopathic non-ischaemic dilated cardiomyopathy and sustained VT. Group C: diagnosed with pulmonary/systemic sarcoidosis and being screened for CS.

Purpose:

1. To assess feasibility of simultaneous FDG PET/CMR
2. To compare and contrast the sensitivity and specificity of FDG PET versus CMR (including examining early diagnosis of CS, how to characterise, quantify and monitor CS).

Primary Outcome measure:

Clinical improvement at 3, 6, 12, 18 months

Secondary Outcome measures:

Total mortality, cardiovascular mortality, heart failure hospitalization, change in LVEF from baseline, change in disease activity, arrhythmia burden