Gut bacteria by-products can trigger heart failure

Posted Nov 15, 2014 by Tim Sandle
A chemical produced by intestinal bacteria has been linked to heart failure, according to a new study. The chemical and heart risk link has been established previously, but the association with bacteria is new.
Scientists have claimed that advanced tissue engineering techniques  such as freeze-drying heart val...
Scientists have claimed that advanced tissue engineering techniques, such as freeze-drying heart valves after cellular materials have been removed and storing the biological scaffolds for later transplanting, could revolutionize the field of reconstructive heart surgery.
Andy G/file (CC BY-SA 2.0)
The chemical is called trimethylamine N-oxide (TMAO). The chemical has an association with heart disease. However, more importantly in the context of disease prevention, the chemical may prove to be significant as a signal for diagnostic tests for predicting future heart attacks.
The connection between the chemical and bacteria came about after researchers tracked 720 heart failure patients over a five-year period. The researchers discovered that patients who had high levels of TMAO then they had more than a 50 percent mortality rate over 5 years.
Taken this correlation, the researchers then found that TMAO is produced when certain intestinal bacteria (such as species of the bacterial genus Acinetobacter) digest certain dietary components that are found in red meat, egg yolks, liver and some energy supplements.
These foods contain carnitine. If the bacteria that are capable of converting these substances to TMAOs are present in the gut then it follows that the concentration of TMAO in the blood increases. TMAO alters cholesterol metabolism in the intestines, in the liver, and in artery wall. Furthermore, TMAO may be involved in the regulation of arterial blood pressure and aetiology of hypertension. These are all factors associated with an increased risk of a heart attack.
The research was conducted at Cleveland Clinic and the findings have been published in the Journal of the American College of Cardiology. The paper is titled “Prognostic Value of Elevated Levels of Intestinal Microbe-Generated Metabolite Trimethylamine-N-Oxide in Patients With Heart Failure.”