My Husband Is 60 Years Old. He Has Had A

My husband is 60 years old. He has had a stent put in for blockage 7 or 8 years ago. He has smoked since he was 16 and does not eat healthy at all. He is very active in his work and we farm, so I would say he has moderate exercise. In the past couple of years I have noticed an increase of his hands having tremors. Is this possibly related to a heart condition?