Heart Experts Cast Doubt on Claims That Russian Skater’s Drug Test Was Contaminated by Her Grandfather’s Medicine

The latest revelations about Russian figure skater Kamila Valieva’s doping case raise more questions about the substances found in her sample—and the reasons why the 15-year-old might have failed the drug test. TIME asked leading experts to help make sense of the claims, which have upended the women’s figure skating competition at the Beijing Olympics and cast a larger pall over the sport.

At the hearing held on Sunday by the Court of Arbitration for Sport (CAS), anti-doping authorities revealed that Valieva tested positive for three heart treatment drugs, one of which is banned as a performance-enhancer by the World Anti-Doping Agency.

In addition to trimetazidine (TMZ), the prohibited substance, the New York Times reported that Valieva’s sample also contained hypoxen and L-carnatine, a supplement. All three are used for patients with angina, to improve blood flow and enhance function of the heart when it lacks oxygen.

When she submitted a sample for testing in December, Valieva declared that she was taking hypoxen and L-carnatine, along with another compound, supradyn, a supplement that boosts immunity, according to documents reviewed by the Times. All three of those substances are allowed.

To explain the presence of the prohibited drug, TMZ, Valieva’s lawyer argued that she was “contaminated” with the medication, potentially via contact with her grandfather, who appeared by video to say that he takes the medication. TMZ is prescribed to treat angina, because it can help increase blood flow to the heart and help the heart to work more efficiently. It’s not approved in the U.S., but is approved by the European Medicines Agency and other regulatory bodies.

READ MORE: Kamila Valieva Is Allowed to Skate. The Battle Over Her Drug Test Is Just Beginning

Russian newspaper Pravda reported that Valieva’s lawyers argued during the hearing, “There can be completely different ways how it got into her body. For example, grandfather drank something from a glass, salvia got in, this glass was somehow later used by an athlete. Or the drug lay down on some surface, traces remained, the drug lay down on this surface, which the athlete then drank.”

Can the drug pass that easily from one person to another, and if so, would it appear in the recipient’s urine sample, as Valieva’s lawyer is claiming? “It reminds me of kids I knew who said they got venereal disease from the toilet seat,” says Dr. Steven Nissen, a cardiologist at the Cleveland Clinic.

Nissen says he’s not familiar with how sensitive the assays, a scientific measurement procedure, being used by the WADA lab are, but says that testing positive for a substance by drinking from the same glass as someone taking it is “very far-fetched.”

“It’s hard to be definitive without knowing the assay [test] sensitivity, but it seems very, very unlikely,” he says.

Valieva’s lawyer also claimed she might have come into contact with the medication on a surface and then somehow ingested it. Dr. Donald Lloyd-Jones, president of the American Heart Association and chair of preventive medicine at Northwestern University’s Feinberg School of Medicine says, “I’ve seen no evidence it gets absorbed through the skin.” He admits he doesn’t know how much of the drug was detected in the athlete’s sample, which would inform whether a brief contact with a small amount of the drug could explain her positive test.

Lloyd-Jones also points out patients have to take TMZ three times a day, because it is metabolized by the body and excreted relatively quickly. Taken at the approved dose, the drug would reach its peak levels in the blood in anywhere from two to six hours, and the majority would be cleared within 24 hours. “It would seem implausible that a little bit on a glass or on her skin would have resulted in a positive test unless it happened to be just before she provided the sample,” he says. “One can draw inferences that either the exposure was very recent, very shortly before her test, or that she was exposed more chronically.”

Ideally, a performance-enhancing drug has the same feature. “The ideal performance-enhancing compounds get in to improve performance, then get out without leaving a trace,” says Lloyd-Jones.

READ MORE: Olympians Let Loose on Kamila Valieva and Russian Doping Controversy

While TMZ is not available in the U.S., Nissen says there is a similar drug, ranolazine, that is approved by the Food and Drug Administration. That drug also shifts the energy source that heart cells use from fatty acids to glucose, which is more efficient. “That’s why it works for angina,” says Nissen. “It allows people to do more with less blood flow. Conceivably for an athlete, it would have similar benefit and would make the heart work more efficiently and give them a little edge.”

Lloyd-Jones says this metabolic pathway also results in less build-up of lactic acid, which can cause muscle fatigue. “There are data from small trials in patients who have heart failure that that seem to indicate better heart performance for those who have a failing pump,” he says. “But whether that translates into the same benefit in a young, healthy person—I don’t think we know.”

It’s also unclear what the consequences are of taking these compounds while the body is younger. “It’s certainly concerning, especially in a young person whose body is still developing,” says Lloyd-Jones. “We really don’t understand the long term effects of changing someone’s physiology at this age.”

While the Court of Arbitration for Sport determined Valieva could compete in Beijing, her doping violation case remains unresolved, pending further investigation. That means the gold she and her teammates won in the team event, and any medal she wins in the women’s event could potentially be stripped if anti-doping officials conclude she doped and competed with an unfair advantage.

That will hinge on additional testing of a second sample, provided from the same urine as her first, that will be analyzed to confirm the positive results from the first sample.