This study compares the pacemaker's automatic pacing threshold measurements to the manual measurements conducted by a health care provider.

The purpose(s) of the study is (are) to evaluate several features available in EnPulse Series pacemaker and report the long term benefit of Atrial Capture Management (ACM) and Ventricular Capture Management (VCM) as demonstrated by accuracy in comparison with manual measurements and variability of ACM and VCM thresholds.

In addition, an evaluation of the timesaving and qualitative benefits of the device feature known as Quick Look II (the computer interface screen of the device programmer) will be measured through the use of a questionnaire completed by the health care professionals involved in patient follow-up care.

This is a one-to-one randomized, multicenter, prospective study in which patients receiving new EnPulse pacemaker implants will be randomized to each of three study arms, 1) routine manual follow-up and follow-up using the automatic features; 2) ACM diagnostics detail on or VCM diagnostics detail on; 3) PMOP on / off or PMOP off / on (6 month cycle).

Inclusion Criteria:

• Patients that meet ACC/AHA/NASPE 2002 class I or II dual chamber pacing indications (intended for a Pacing Mode programmed to DDD or DDDR)

Exclusion Criteria:

• Patient with mechanical tricuspid heart valves
• Patients with medical conditions that preclude the testing required by the protocol or limit study participation