Another well-known risk factor for SCD is abnormal sympathetic innervation. The most robust clinical test of sympathetic innervation to date is Iodine-123 Metaiodobenzylguanidine (MIBG) imaging with gamma scintigraphy. MIBG imaging has emerged as one of our strongest predictors of SCD by detecting sympathetic nervous system abnormalities in patients with HF. Preclinical and clinical evidence suggests that myocardial inflammation adversely affects myocardial innervation.