No autopsy was done, according to the county coroner.
Amick says Boyd had a number of medical problems, including heart failure, kidney failure and liver problems.More news: The Trump-Kim Summit: What You Need to Know
Boyd's death comes one year after he and his mother were involved in a serious auto accident, in which their vehicle ran off the right side of the road and struck a tree.
Boyd captivated audiences with his booming voice and quickly became a fan-favorite while competing on America's Got Talent back in 2008.
Boyd opened up about the accident in an interview with Southeast Missourian earlier this year. "I shattered a lot of bones, and shattered my hip, which has left me nearly unable to use that leg for now", he told the outlet in February.More news: "Fox & Friends" Anchor Accidentally Calls Donald Trump A "Dictator"
"I didn't realize we were poor until my mama told me I was, but we got through", he said on the show.
Boyd released two albums following his AGT victory, My American Dream in 2009 and My Christmas Wish in 2013.
He told the outlet that he planned to release his third album "In the Middle of it All" in 2019. Just be grateful that you survived.More news: Fifa WC 2018 : 32 Teams | 12 Stadiums
He was also very involved in politics and campaigned for a Missouri District 149 House Seat in 2014.
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