The average life expectancy for someone with a pacemaker is no different from that of a person without a pacemaker. According to Science Daily, pacemakers implanted for slow heart rhythm restore life expectancy back to normal levels.
A U.S. government report released in 2014 projects life expectancy for women at 81.2 years and men at 76.4 years. This is a rise in life expectancy from the 2012 report, which put the average at 78.8 for women and 74.4 for men. Doctors are unclear as to whether genetics play a role in life expectancy but are confident that behavior plays a large part.