They both were on warfarin and fared very well their whole lives. Both had heart conditions due to Rheumatic Fever as teenagers.
My grandfather had his mechanical valve surgery in 1972 at the age of 48 and said his heart was stronger and he felt better every year he was alive. He died in 1988 due to pancreatic cancer, which though detected early because of the blood thinner going wonky, did not respond to treatment. As for blood thinner, he did have occasional issues with bloody noses.
My mother in law had a heart valve repair in 1963, which involved a strategically placed set of sutures. Then in 1988 she had it replaced with a mechanical valve at the age of 55. She had other health issues as she aged, but her heart was not one of them when she died at the age of 80. She never seemed to have an issue with warfarin other than easy bruising.
There are better blood thinners out there now. My father takes a blood thinner due to having a blood clot in his leg a decade ago. He started on warfarin, but his doctor switched him to a new one that requires less tweaking and is less influenced by illness or foods.
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