Lyndsi Johnson, of Bangor in the US state of Maine, has a condition that makes her heart beat too fast when she stands or sits upright. She was medically discharged from the US Navy in 2018.Lyndsi Johnson, of Bangor in the US state of Maine, has a condition that makes her heart beat too fast when she stands or sits upright. She was medically discharged from the US Navy in 2018.Read MoreHealth News | Mail Online