CLEVELAND, Ohio -- A Cleveland Clinic doctor who lost a bid for the Libertarian Party's presidential nomination died of natural causes, the medical examiner says.

Marc Feldman, 56, of Beachwood died from cardiovascular disease, according to the Cuyahoga County Medical Examiner's Office.

Feldman was found dead inside a room at a Brook Park hotel in June.

An employee at the America's Best Value Inn in the 14000 block of Brookpark Road called police June 22 after a woman called the front desk from Feldman's room and said he was unresponsive, police reports show.

Feldman was not breathing when first responders arrived minutes later. He was pronounced dead at the scene.

In May, Feldman lost the nomination to represent the Libertarian Party in the November presidential election. The party selected former New Mexico Gov. Gary Johnson.

Feldman was the section head of anesthesia for the Cole Eye Institute and director of the Cole Eye Institute Operating Rooms at the Cleveland Clinic.

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