Autopsy: Medical emergency caused man to hit tree

A 78-year-old Arlington Heights man who died after his vehicle struck a tree late Wednesday afternoon suffered a medical emergency before his car veered off the road, according to autopsy results released Thursday.

Myles Martin died of a heart condition and multiple injuries sustained in the crash, according to the Cook County medical examiner's office.

A witness called 911 at 4:09 p.m. to report the accident on the 1000 block of South Walnut Road. Tire impressions in the snow indicate the car was being driven on the west-side shoulder of Walnut road before crossing the road and striking a parkway tree, police said.

Investigators are asking anyone who witnessed the accident to call police at (847) 368-5300.