American chess grandmaster Daniel Naroditsky died last year after suffering a sudden heart rhythm disturbance, with an underlying heart condition identified as the primary cause, according to a report released by North Carolina medical authorities.
The 29-year-old was found dead at his townhome in Charlotte in October 2025. At the time, police said his death was being investigated as a possible overdose or suicide, and no cause had been made public.
The medical examiner’s investigation, conducted by Dr James R Lozano and obtained by the Guardian on Thursday, concludes that Naroditsky died from a probable cardiac arrhythmia caused by undiagnosed systemic sarcoidosis, an inflammatory disease that most commonly affects the lungs but can also involve the heart. Methamphetamine and kratom (mitragynine) use were listed as contributing conditions, though the report states that the levels detected were not considered toxic or lethal on their own. The manner of death was ruled an accident.
According to the report, postmortem radiographic imaging revealed extensive granulomatous lung disease, findings that are “highly suggestive” of sarcoidosis. Cardiac sarcoidosis can disrupt the heart’s electrical system and is a known cause of sudden death, sometimes without prior diagnosis or warning symptoms.
The medical examiner noted that sudden unexpected death is the presenting manifestation in a significant proportion of cardiac sarcoidosis cases. No autopsy was performed, but investigators said the totality of radiographic, toxicological and circumstantial evidence supported the conclusion.
Toxicology testing detected methamphetamine and amphetamine in Naroditsky’s blood, with the amphetamine present as a metabolite of methamphetamine rather than evidence of separate ingestion. Compounds associated with kratom, a plant-based supplement increasingly used for stimulant or pain-relieving effects, were also found. Review of North Carolina prescription records showed no prescriptions for amphetamines or methamphetamine issued to Naroditsky.
The report states that there was no evidence of intentional or unintentional overdose, no signs of traumatic injury and no indication of foul play. Investigators said Naroditsky appeared to have died suddenly, without signs of acute distress.
Naroditsky was discovered unresponsive on his living room couch by close friends Oleksandr Bortnyk, a fellow grandmaster, and Peter Giannatos, founder of the Charlotte Chess Center, where Naroditsky served as head coach and grandmaster-in-residence. Friends went to check on him after he stopped responding to calls and messages.
In the days before his death, Naroditsky had been under intense public scrutiny following cheating allegations made by former world champion Vladimir Kramnik, claims Naroditsky consistently denied. The medical examiner’s report notes that investigators considered stress related to those allegations while evaluating the possibility of overdose or suicide, but ultimately found no evidence to support either.
In a statement issued this week, Kramnik expressed condolences to Naroditsky’s family and rejected claims that his conduct contributed to the grandmaster’s death. He said that following Naroditsky’s passing, he and his family were subjected to harassment and death threats, prompting him to consider legal action.
“I deeply regret that this profound tragedy was exploited by various individuals and groups to advance their own agendas,” Kramnik said. “There can be no justification for such immoral conduct.”
The International Chess Federation (Fide) has said it is reviewing whether Kramnik should face disciplinary action for public statements made about Naroditsky before and after his death. Potential sanctions include fines or suspension. Fide did not immediately respond to a request for comment from the Guardian following the release of the medical examiner’s report.
Naroditsky’s death marked a devastating loss for American chess. A prodigy who learned the game as a child in California, he became a grandmaster at 18 and later graduated from Stanford University with a degree in history. Known to fans as “Danya”, he rose to prominence not only for his elite play but for his rare ability to explain the game with clarity, patience and warmth.
He was one of the most influential figures of chess’s pandemic-era boom, amassing more than 800,000 followers across YouTube and Twitch through instructional videos and live commentary. He also remained an elite competitor, winning the US Blitz Championship only months before his death.
Tributes poured in from across the chess world after his passing. Magnus Carlsen called him “a resource to the chess community”, while Hikaru Nakamura described him as “the best of us”. Fide later announced plans for a memorial award in Naroditsky’s name.
