Is the intestinal microbiota involved in heart failure?
Patients with heart failure have a less diverse intestinal microbiota than healthy subjects, suggesting that intestinal dysbiosis could potentially be involved in the pathophysiology of this condition.
The five-year survival rate for patients with heart failure is under 50%. Faced with this fact, some researchers took an interest in organs other than the heart in an attempt to better understand the pathophysiology of heart failure. Previous studies have shown a connection between anomalies in the intestinal function and heart failure, suggesting that the intestinal microbiota may potentially play a role in the appearance and progression of the disease. The intestinal microbiota of patients with heart failure, examined by a German team, showed low bacterial diversity and a deficiency in many important bacterial species. The researchers systematically analyzed the composition of the intestinal microbiota in twenty patients with heart failure with reduced ejection fraction (LVEF ≤ 35%) due to ischemia or dilated cardiomyopathy. They sequenced the bacterial 16S ribosomal RNA from stool samples and drew up a bacterial profile for each patient. The results showed that patients with heart failure had a less diverse microbiota than control (healthy) subjects), with a significant depletion of the Coriobacteriaceae, Erysipelotrichaceae, and Ruminococcaceae families and the Blautia and Collinsella genera, as well as two other unknown genera from the Erysipelotrichaceae and Ruminococcaceae families. These anomalies were found in all patients, compared with healthy subjects (bacterial signature of the disease). It is currently difficult to determine whether these anomalies are the cause or the result of heart failure, but the role of certain bacteria like Blautia or Faecalibacterium, which are associated with anti-inflammatory mechanisms, suggests that dysbiosis could be a risk factor and an early marker for this cardiac disease.
Luedde M et al. Heart failure is associated with depletion of core intestinal microbiota. 8. ESC Heart Fail. 2017 Aug;4(3):282-290. doi: 10.1002/ehf2.12155. Epub 2017 Apr 21