Pop star George Michael died of natural causes related to heart and liver problems, a coroner confirmed Tuesday. The Wham! singer, who died on Christmas Day at age 53, suffered a dilated cardiomyopathy with myocarditis and fatty liver, according to Darren Salter, senior coroner for Oxfordshire, the BBC reported. Police originally said Michael’s death at his home in Goring-on-Thames, Oxfordshire, was unexplained but not suspicious. An initial post-mortem examination was “inconclusive.” The singer’s funeral had been on hold until toxicology tests were completed, Radar Online reported. In the past, Michael admitted to drug use but denied he was an addict. British cops grilled his former lover in January, over fears the singer died of a drug overdose.