Quality of life and economic issues were assessed in patients at entry and annually for three years. Questionnaire-based measures of health status and quality of life were compared in the two pacing groups for the entire population and subgroups defined by age and gender. The economic substudy measured the comparative costs, both direct and indirect medical and nonmedical, of the two pacing modes in an attempt to determine the most cost-effective approach to pacemaker treatment of sick sinus syndrome.