Kile died of natural causes, according to Edmund Donoghue, the county's chief medical examiner.
Toxicology tests did show evidence of marijuana use, although it was probably indicative of drug use weeks before and did not contribute to Kile's death, Donoghue said.
Tests were negative on steroids, alcohol, cocaine and ephedrine, a substance commonly found in dietary supplements banned by some sports.
Kile, 33, had a 90 percent blockage in two coronary arteries, Donoghue said, confirming his preliminary analysis shortly after the death. He also had an enlarged heart and a blood clot in one of the coronary arteries.
Kile was found dead in the team's Chicago hotel on June 22. Workers at the downtown Westin Hotel found the body after they forced their way into Kile's 11th-floor room after being called by the team.
A substance believed to be marijuana was found in the hotel room.
Kile's heart condition, called coronary atherosclerosis, is commonly known as hardening of the arteries.
Kile's father died shortly after a heart attack in his mid-40s in 1993.
The Cardinals had said the 6-foot-4 pitcher had no known health problems and was not on medication.