BRIGHTON, Colo. – A Platte Valley Ambulance Service battalion chief who has saved countless lives is now in the ICU with heart failure. Dave Christenson was suffering shortness of breath before he went to the doctor and found out he had heart failure. The acting chief paramedic, Chris Mulberry, said this came as a surprise, since he is pretty active. They are supporting him through this change, and are waiting with open arms for him to come back.