Sympathetic Innervation of the Heart and Cardiac Resynchronization Therapy(CRT)

Inclusion Criteria: * Indication for CRT * Stable optimal medication * Non ischemic cardiomyopathy Exclusion Criteria: * Age less then 18 years * Previous CRT * Clinically relevant valvular heart disease or coronary artery disease * Acute or chronic infection * Untreated clinical hypo- or hyperthyroidism or \< 3 months euthyroidism * Uncontrolled hypertension, defined as a systolic blood pressure \> 160 mm Hg and/or a diastolic blood pressure \> 95 mm Hg * A concurrent medical condition (i.e. alcohol or drug abuse or a severe progressive extra cardiac disease or M. Parkinson) or is unlikely to comply with the protocol * Participation to a previous protocol involving radioactivity in the past year * Pregnancy