Does it matter that i have a heart condition if i abuse laxatives?

Yes: Overuse of laxatives is a common cause of low potassium which is an important contributing factor to cardiac rhythm disturbances. Have you tried eating a high fiber diet? A bowl or two of all-bran a day will usually work wonders for people with chronic constipation. If you don't like the taste, mix it with your favorite cereal and/or add raisins or your fruit of choice.