Inclusion Criteria- Patient has symptomatic bradycardia and is a candidate for first pacemaker implantation
- Patient has high risk of being pacemaker dependent by (at least one of the following):
1. Average heart rate of 60 or less on pre-implant Holter
2. Maximal heart rate of 60 in patient on telemetry monitoring 12 hrs preoperatively, when not under medications decreasing heart rate, or under chronic medical treatment inducing bradycardia, which is unlikely to be changed
3. First degree AV block with PR intervals > 300 ms, or second degree AV block at heart rates <= 80 bpm.
4. Dependence for 12 hrs when on temporary pacemaker set at 50 bpm if bradycardia is not secondary to medication, or under chronic medical treatment inducing bradycardia, which is unlikely to be changed.
Exclusion Criteria- Age <= 65 years
- Chronic Atrial Fibrillation
- Indication for ICD
- Non-cardiovascular death is likely to occur within 3 years
- Geographical, social, or psychiatric reasons making follow-up problematic