Kristoff St. John died from heart disease as a result of an alcohol binge
https://www.tmz.com/2019/03/19/young-and-restless-kristoff-st-john-cause-death-heart-disease/
The Los Angeles coroner's office has released why The Young and the Restless star died last month at age 52. According to TMZ, "the cause of death is listed as hypertrophic heart disease and is categorized as accidental.... The disease makes it difficult for the heart to pump blood and often goes undiagnosed."