title: The natural history of the sick sinus syndrome.
mesh_terms: D001146:Arrhythmia, Sinus / Q000209:etiology; D006323:Heart Arrest / Q000209:etiology; D006327:Heart Block / Q000209:etiology; D006331:Heart Diseases / Q000150:complications*; D006333:Heart Failure / Q000209:etiology; D006801:Humans; D012849:Sinoatrial Node