Objective  To evaluate the general clinical features, clinical outcomes, and safety of permanent pacemaker implantation for extremely elderly patients over 90 years old.

  Methods  Clinical data of 21 patients, including age, sex, indications of the operation, comorbidities, assessment of cognitive abilities, complications, changes of preoperative and postoperative renal and cardiac functions. Follow-up results after1 year of surgery were observed.

  Results  All cases succeeded in pacemaker implanting, and symptoms of bradycardia disappeared after surgery. Of these patients, 1 case occurred bradycardia caused by pacemaker implantation, and ceased after programmable adjustment of pacemaker parameters; 1 had worsened postoperative heart failure, and was discharged after medical treatment, but died of lung infection after 10 months of operation; 1 case died of malignant brain tumor after 11 month of operation. No other complications were observed during the operation, and no significant changes in renal function and left ventricular ejection fraction (LVEF) were found at 12 month after the operation compared with preoperation.

  Conclusion  Permanent pacemaker implantation is effective and safe in extremely elderly patients. No significant changes in renal function and LVEF at 12 month after operation were seen compared with preoperation.