Abstract
Introduction
Heart failure with preserved ejection fraction (HFpEF) represents a major challenge in modern cardiology. As described previously, in HFpEF comorbidities promote a systemic inflammatory state, leading to diffuse myocardial fibrosis resulting in myocardial stiffening. Gut dysbiosis which is considered as the novel source of chronic systemic inflammation has been actively investigated as the risk factor for the development and aggravation of cardiovascular diseases including heart failure. Cardiac magnetic resonance T1-mapping is a novel tool, which allows noninvasive quantification of the extracellular space and diffuse myocardial fibrosis. Moreover, the extracellular volume (ECV) fraction can be calculated, providing information on the relative expansion of the extracellular matrix, thus being a noninvasive alternative to myocardial biopsy studies.
Purpose
The research was aimed at investigating the correlation between the left ventricular ECV and gut microbial genera in patients with HFpEF.
Methods
42 patients with confirmed HF-pEF (mediana and interquartile range of age 67 [64; 72] years, 47% men, body mass index <35 kg/m2 with no history of myocardial infarction or diabetes mellitus) were enrolled in the study. The patients underwent transthoracic echocardiography with Doppler study, HF-pEF was confirmed according to the recent ESC guidelines (based on E/e' ratio, N-terminal pro-B type natriuretic peptide >125 pg/ml and symptoms of heart failure). The intestinal microbiome was investigated using high-throughput sequencing of bacterial 16S rRNA gene. As the last step of research T1-myocardial mapping with the modified look-locker inversion-recovery protocol (MOLLI) sequence at 1.5 Tesla was performed to assess left ventricular extracellular volume fraction.
Results
The mean±std in ECV was 31.02±4.4%. The relative abundance (%) of the most prevalent phyla in gut microbiota was 48±22.5 for Firmicutes, 47.4±22.8 for Bacteroidetes and 1.5 [1.5; 2.5] for Proteobacteria. The analysis showed significant negative correlations between ECV and the following bacterial genera: Faecalibacterium (r=−0.35), Blautia (r=−0.43), Lachnoclostridium (r=−0.32). Moreover ECV positively correlated with Holdemania (r=0.4), Victivallis (r=0.38), Dehalobacterium (r=0.38), Enterococcus (r=0.33) and Catabacter (r=0.32). All correlation values with p<0.05.
Conclusion
We discovered both negative and positive significant correlations between ECV – the non-invasive marker of myocardial fibrosis and several bacterial genera, which may have negative impact on myocardial remodeling in HF-pEF.
Funding Acknowledgement
Type of funding source: None
Current understanding of gut microbiota alterations and related therapeutic intervention strategies in heart failure
