The medical examiner listed cardiovascular disease after a response on Mount Wilson Trail.
SIERRA MADRE, Calif. — Composer and music professor Mark Smythe died May 9 after a medical emergency on Mount Wilson Trail, where friends and hikers started CPR before rescuers reached the rugged San Gabriel Mountains route, authorities said.
Smythe, 53, was later identified by the Los Angeles County Medical Examiner. Officials said no foul play was suspected. The medical examiner listed his cause of death as atherosclerotic cardiovascular disease, a condition involving plaque buildup in artery walls. His death drew attention across Los Angeles music circles and came one week after another hiker died after a fall on the same trail.
Emergency crews were called at 9:43 a.m. to a section of Mount Wilson Trail north of Rescue Ridge after a report that a hiker had become unresponsive. Members of the Sierra Madre Search and Rescue Team reached the area and found Smythe’s friends and other hikers already performing CPR. Sierra Madre firefighters also responded and provided medical care. Smythe was pronounced dead at the scene, and his body was recovered from the mountain later that afternoon. The Sierra Madre Police Department and Arcadia Police Department also responded during the incident. Sierra Madre police handled the investigation with the medical examiner’s office.
Officials first described the death as a medical emergency and did not release Smythe’s name until after county identification. The case was not reported as a fall. The medical finding clarified the cause after early reports focused on the trail’s steep terrain and a second fatal response in the same area. Atherosclerotic cardiovascular disease can affect blood flow to the heart and has been linked to heart attacks. Authorities did not say whether Smythe had known heart problems or whether he had shown symptoms before he collapsed. His companions and nearby hikers were credited for trying to help before rescue crews arrived.
Smythe was a New Zealand-born composer of choral, film and concert music who lived in Los Angeles. He served as department chair for Composing for Visual Media at the Los Angeles College of Music and also taught media composition at California State University, Northridge. His score for the Hulu film “The Reef: Stalked” was nominated in 2023 for honors from the SCL Awards and the World Soundtrack Awards. He also was selected as a composer fellow for the 2024 Choral Arts Initiative PREMIERE Project Festival, where his choral work “Song of the Sea, Part I” was performed.
Tributes from family, friends and fellow composers followed the news of his death. Composer Bear McCreary said Smythe was a prominent figure in the Los Angeles film scoring community and called the news “awful and surreal.” Kate Ward-Smythe, Smythe’s sister, described him as a “fiercely talented” composer and said he died while doing something he loved, hiking in the hills. Colleagues remembered him as a teacher, collaborator and supporter of other musicians. His death came as students and faculty at the Los Angeles College of Music were nearing the end of an academic term.
The Mount Wilson Trail begins in Sierra Madre and climbs into the San Gabriel Mountains toward Mount Wilson, a peak known for its observatory and views over the Los Angeles basin. The route includes steep, exposed and rocky sections. One week before Smythe’s death, 66-year-old John McIntyre died after falling from the trail into a ravine. That fall was reported at about 2 p.m. May 2. Police closed the trail during the response, and search and rescue crews used the rugged terrain to locate and recover McIntyre. County officials later identified him and said he died from blunt force trauma.
The two deaths brought renewed attention to a trail that had recently reopened after fire damage in the area. Outdoor reports and rescue officials have described parts of the route as loose, exposed and steep, with sections where a slip can have serious consequences. Volunteers had worked on trail repairs after the Eaton Fire damaged parts of the surrounding landscape. Smythe’s death, however, was tied by the medical examiner to cardiovascular disease rather than a fall or outside injury. Police did not report signs of a crime in either the medical emergency response involving Smythe or the earlier fatal fall involving McIntyre.
As of May 13, Sierra Madre police and county officials had released Smythe’s identity and medical cause of death, and no criminal investigation had been announced. His death remains marked by two public records: an emergency response on a mountain trail and a music community mourning a teacher whose work reached film, concert halls and classrooms.
Author note: Last updated May 13, 2026.