A Lake Placid Volunteer Ambulance Service truck leaves the scene of where Colin Plumadore, 54, of Saranac died after trying to assist a stand-up paddleboarder who had fallen into Mirror Lake. (Enterprise photo — Griffin Kelly)

LAKE PLACID — A man who died on Mirror Lake Monday was determined to have suffered a heart attack.

Colin Plumadore, 54, of Saranac died on Mirror Lake after exerting himself while trying to help someone who had fallen in the water, according to Essex County Coroner Frank Whitelaw.

In a text Tuesday, Whitelaw said, “Plumadore’s autopsy was performed by Dr. Francis Varga at Adirondack Medical Center today. The cause of death death is a medical issue, and it was not drowning.”

Whitelaw later specified that it was a heart attack that killed Plumadore.

A relative and a friend of Plumadore both said they prefer not to talk about him at this time.

At around 11 a.m. Monday morning, Plumadore was rowing a guideboat in Mirror Lake about 100 yards off shore. His daughter was rowing a separate guideboat. Plumadore went to assist a stand-up paddleboarder in the water when he overexerted himself, slumped forward and fell into the lake.

State police told WPTZ-TV of Plattsburgh that the paddleboarder did not suffer any injuries. State police did not respond to this newspaper’s inquiries. Village police were also present at the scene Monday but said they couldn’t provide information because it was in state police jurisdiction.

Plumadore had a life jacket in his boat but was not wearing it, according to Whitelaw. The state Department of Environmental Conservation requires every boat to have a personal flotation device readily available for each passenger, but they don’t need to wear them.

People retrieved Plumadore and brought him to shore, where he had no pulse or respiratory activity, Whitelaw said. A 911 call came into emergency services at 11:05 a.m. Members of the Lake Placid Volunteer Ambulance Service arrived and performed life-saving measures, to no avail.