Electric Stimulation Therapy Diseases 4 Cardiac Pacing, Artificial 2 Cardiovascular Diseases 2 Heart Diseases 2 Medicine 2 Neurology 2 Therapeutics 2 Brain 1 Cardiac pacing 1 Central Nervous System 1 Central Nervous System Diseases 1 Central Nervous System Stimulants 1 Central nervous system 1 Clinical Medicine 1 Clinical Trials as Topic 1 Congestive heart failure 1 Controlled Clinical Trials as Topic 1 Deep Brain Stimulation 1 Defibrillators 1 Defibrillators, Implantable 1 Diagnostic Techniques and Procedures 1 Electrical Equipment and Supplies 1 Electricity 1 Electrodes 1 Electrodes, Implanted 1 Electrotherapeutics 1 Environment and Public Health 1 Epidemiologic Methods 1 Epidemiologic Studies 1