Higher Trimethylamine N-Oxide Levels Linked to Greater Risk of Heart Problems
SCIENTISTS have found that higher levels of the trimethylamine N-oxide (TMAO) molecule produced in gut bacteria from components such as dairy products in blood is associated with a higher risk of major adverse cardiovascular events in patients with suspected heart problems.
The team think that their research findings mean TMAO testing could be used to identify higher-risk patients within days of being admitted to hospital or years later. The scientists also reported that TMAO levels could predict adverse events in patients who did not have the troponin T protein in their blood. Measuring for the protein is a standard diagnostic test for patients with suspected heart problems.
Prof Thomas Lüscher, Chairman of Cardiology, University Hospital Zürich, Zürich, Switzerland, and the team examined the TMAO levels in the blood of 530 patients in the USA who arrived at an emergency department with chest pains. They also looked at TMAO levels of 1,683 patients with chest pains who received a coronary angiography within 5 days of being admitted to a hospital in Switzerland. Patients were followed-up for several years after to monitor any major adverse cardiovascular events.
According to Prof Lüscher, after adjusting for risk factors, patients in the USA with higher TMAO levels were more likely to experience a major adverse event. “When compared with patients with the lowest TMAO levels, those with levels in the top 25% were around six times more likely to die, suffer a heart attack or stroke, or require revascularisation at 30 days and 6 months, and nearly twice as likely to die within 7 years,” he said. Prof Lüscher also added that among patients without elevated levels of troponin T when first admitted to hospital, the top 25% of this group had a nearly six-fold higher risk of a major adverse event.
“We think that rapid TMAO testing could now contribute to the identification of higher risk patients, with the potential to speed up the time between initial evaluation and cardiac catheterisation. This could help salvage more of the heart muscle that is under stress, as time is muscle,” Prof Lüscher said.
Jack Redden, Reporter