What factors does the final result of a cardiac rehabilitation program depend on?

Patient & therapist. Important patient factors in determining success of cardiac rehab are motivation to make healthy lifestyle changes, and compliance with advice from medical professionals. Psychological factors, e.g. Depression and anxiety, are critical factors that influence this. Having a personable and invested therapist, who takes an interest in you as an individual, is paramount as well.
Many. Cardiac rehab is beneficial for many cardiac patients. Most patients will have an increase in their overall activity capacity. The magnitude of this increase depends upon how in shape you are to start, the length of rehab, and if the patient continues to exercise after rehab officially ends.