The actor, who played Mr Spock in the long-running series, passed away at his Bel Air home on Friday.
Last week Nimoy was taken to UCLA Medical Center in Los Angeles with chest pains and he has entered hospital a number of times over the last few months.
Last year, he revealed he was suffering from chronic lung disease, despite stopping smoking more than 30 years ago.
Symptoms of Chronic Obstructive Pulmonary Disease include coughing, chest infections and breathlessness.
Nimoy was recently pictured looking frail and using an oxygen cylinder as he was wheeled through JFK airport. He has played the famous Vulcan character since 1966 and was the only actor from the original series to return for JJ Abrams’ recent film versions.