Hi My dad had a severe heart attack on 2014. During those times our cardio doctor suggested that due to severe attack my dad's creatinine and urea level highly increased so that bypass and angioplasty can't be done. We are taking tablets since 8 months. But now my dad is telling that he feels good, he daily goes for a walk about 30 minutes. I just need to know is walking good for his health and walking for long distances will make his heart to function good?