THE IMPACT OF PACEMAKER IMPLANTATION ON COGNITIVE-FUNCTIONING IN ELDERLY PATIENTS

Objective: To describe and quantify the impact of pacemaker implantation on cognitive functioning in the elderly. Design: Prospective case-control, non-randomized trial, Data were collected from clinical and family interviews and from a psychological test battery. Setting: Pacemaker clinic in a tertiary care hospital. Participants: Nineteen elderly (65+ years) patients undergoing new or replacement pacemaker implantation for dysrhythmias and volunteer controls matched for age, sex, and short Mental Status Questionnaire test results, without dysrhythmia or intervention. Main Outcome Measures: Subjective and clinical impressions based on family interviews; results of psychological test battery before and 6-12 months after pacemaker implantation. Results: Prior to pacemaker implantation, three patients met DSM-III criteria for dementia and two for delirium. Paced patients demonstrated deficiency in immediate memory, language, memory for less structured information, and learning of abstract materials. These deficits were due primarily to the poor performance of patients with complete heart block. Despite clinical and subjective impressions of improvement, there was no change in psychologic test performance subsequent to pacemaker implantation. Conclusions: Impaired cognitive functioning is not always clinically apparent but appears common in patients with cardiac dysrhythmias; it is not altered 6-12 months after pacemaker implantation.