You're right. I heard MLK, had he not been killed in 68, wouldn't have lived much longer anyway because of heart issues that plagued his family.
His brother, A.D. King died of a heartattack at age 38 and three of his children died of heart attacks
"After his death, Martin Luther King's autopsy found that while he was just 39 years old, he had the heart of a 60-year-old. Doctors concluded the pressure he had experienced in his career had stressed and aged his heart."
You are right, there could be things going on beneath the skin that may lead to unknown health problems.