dont take this the wrong way. but you dont need anything for a walk. dont be so paranoid to go out on a walk in friendly neirborhood. the chances you get mugged ,bite by a dog or hit by a car are very slim....so dont worry <img src="/images/graemlins/smile.gif" alt="" /> nothing will happen as long as you use common sense and your brain.
you dont need to take anything other than a bottle of water and a cell phone. the rest to me is over the top. you said you had heart problems so maybe take a pill or two. i suppose you could always talk to your doc.