Lesin who once headed state-controlled media giant Gazprom-Media, also had blunt force injuries to the neck, torso, arms and legs, the U.S. capital's chief medical examiner and the Metropolitan Police Department said in a brief statement.
The incident was under investigation, the statement said.
Local and Russian media have reported that Lesin was found dead inside a hotel room in November in Washington's Dupont Circle neighborhood, which is home to embassies and think tanks.
Russia's RT television quoted family members at the time as saying he had died of a heart attack.
Lesin, who was Russia's minister of press from 1999 to 2004 under President Vladimir Putin, had been accused of censoring Russia's independent media. He became head of Gazprom-Media Holding in 2013 but resigned the following year.