A Glendale student who lost consciousness and drowned while swimming during a high school physical education class last week suffered a seizure before sinking underwater, said Bob Dambacher, a spokesman for the Los Angeles County coroner's office.
An autopsy showed that a cyst on 16-year-old Danny Kupelian's brain triggered the seizure, Dambacher said.
Kupelian, a sophomore at Hoover High School, was swimming the final leg of a 100-yard warm-up when the seizure struck at 11 a.m. last Tuesday, said Vick Pallos, a Glendale Unified School District spokesman.
Students pulled Kupelian out of the water, Pallos said. Rescue officials were called as the school nurse administered cardiopulmonary resuscitation.
Kupelian was pronounced dead about an hour and a half later at Glendale Adventist Medical Center.