Physical Activity and Pacemaker Study

The benefits of habitual physical activity (PA, activities of at least moderate intensity
defined as ≥ 3 metabolic equivalents (METs)) are well-recognized. Emerging information from
large data sets strongly suggest high levels of sedentary behavior, defined as activities
<1.5 METs (equivalent to the amount of energy expended during seated activities such as
computer work) increases the risk of diabetes, cardiovascular disease, and death, independent
of the amount and intensity PA. The increased risk of sedentary behavior appears to be
mediated at least in part by reduced insulin sensitivity, impaired lipid metabolism,
increased vascular inflammation, and increased thrombotic tendencies.

The internal accelerometer embedded in Medtronic pacemakers registers, stores, and reports
total number of "active time" based on a threshold activity intensity level of approximately
70 steps/min (estimated to be > 1.5 METs). This implanted accelerometer, combined with the
regular follow-up required for appropriate care make individuals who have undergone Medtronic
pacemaker implantation an ideal population in which to evaluate the impact of altering
sedentary behavior on mortality and cardiovascular events.

The hypotheses are as follows:

1. a 12 week intervention to increase moderate intensity physical activity delivered at the
point of care in patients with pacemakers will result in parallel increases in active
time as measured by the pacemaker and step count as measured by pedometer.

2. the increase in activity measured by both the metrics in hypothesis 1 will be greater
than with usual care.

Potential subjects who are interested in the study will have a screening visit to determine
whether they meet the inclusion and exclusion criteria. Those who qualify and agree to
participate will be randomized into either the Physical Activity Counseling arm (intervention
arm) or the Patient Usual Care arm (control arm).

Subjects in the interventional arm will be given a pedometer and physical activity counseling
on a regular basis for 3 months. Physical activity data from their external pedometer will be
collected every 2 weeks via phone calls. Accelerometry data from the implanted pacemaker will
be collected from the subject's medical record as pacemaker interrogations are performed
every 3 months as part of routine clinical care. After the initial 3 month interventional
phase is complete, these subjects will be followed for another 3 months with collection of
pedometer as well as accelerometer data as described above.

Subjects in the control arm will be given pedometers for the week prior to pacemaker
interrogation. These subjects will be called to report the number of steps they walked each
day prior to the interrogation. Their accelerometry data will be captured through routine
clinical pacemaker interrogations.

The primary outcome is the physical activity level in each group as measured by the
accelerometer at time 0, 3 months and 6 months. The secondary outcome is the step count in
each group as measured by the pedometer at the same time points.

Inclusion Criteria:

- Age > 55 years old

- Clinical indication for placement of permanent pacemaker

- LVEF of ≥ 50% at the time of or within 72 hours of implantation.

- Able to ambulate

- Average active time of ≤ 2 hours/day based on Revo or EnRhythm Accelerometery read out
for the 3 month period prior to enrollment

- Able to take 650 steps over 10 minutes following pacemaker implantation (~2-2.5 mph
walking speed)

Exclusion Criteria:

- Follow up for implantation planned at a non-study center at the time of implantation.

- Individuals with and expected life span of 1 year or less at the time of implantation

- Known history of cognitive impairment or inability to follow study procedures