If a medication or a medical condition is the cause of constipation, eliminating the offending medication or treating the underlying medical condition may relieve the constipation. However, certain conditions require the use of a medication despite its side effects.
Your heartbeat can be either tachycardic or bradycardic during a heart attack, so no i don't believe you had have a normal pulse rate at the time of a heart attack, normal being around 60-70 beats per minute for an adult. Heart rate does decrease though with age but that doesn't necessarily indicate anything is amiss.
Although a heart attack can lead to a cardiac arrest, they are not the same thing. A heart attack is a sudden interruption to the blood supply to part of the heart muscle. It is likely to cause chest pain and permanent damage to the heart.