A Systemic Perspective of the Link Between Microbiota and Cardiac Health: A Literature Review

Abstract

Cardiovascular diseases (CVDs) are the leading global cause of death, with long-term hospitalization becoming increasingly frequent in advanced or chronic cases. In this context, the interplay between systemic factors such as lipid metabolism, circulating metabolites, gut microbiota, and oral health is gaining attention for its potential role in influencing inflammation, cardiometabolic risk, and long-term outcomes. Despite their apparent independence, these domains are increasingly recognized as interconnected and influential in cardiovascular pathophysiology.

Methods: This narrative review was conducted by analyzing studies published between 2015 and 2024 from databases including PubMed, Scopus, and Web of Science. Keywords such as "lipid profile," "metabolomics," "gut microbiota," "oral health," and "cardiovascular disease" were used. Original research, meta-analyses, and reviews relevant to hospitalized cardiac patients were included. A critical integrative approach was applied to highlight cross-domain connections.

Results and discussion: Evidence reveals significant interrelations between altered lipid profiles, gut dysbiosis (including increased TMAO levels), metabolic imbalances, and oral inflammation. Each component contributes to a systemic pro-inflammatory state that worsens cardiovascular prognosis, particularly in long-term hospitalized patients. Despite isolated research in each domain, there is a paucity of studies integrating all four. The need for interdisciplinary diagnostic models and preventive strategies is emphasized, especially in populations with frailty or immobilization.

Conclusions: Monitoring lipid metabolism, metabolomic shifts, gut microbial balance, and oral status should be considered part of comprehensive cardiovascular care. Gut microbiota exerts a dual role in cardiac health: when balanced, it supports anti-inflammatory and metabolic homeostasis; when dysbiotic, it contributes to systemic inflammation and worsened cardiac outcomes. Future research should aim to develop integrative screening tools and personalized interventions that address the multifactorial burden of disease. A systemic approach may improve both short- and long-term outcomes in this complex and vulnerable patient population.

Keywords: cardiovascular disease; chronic hospitalization; gut microbiota; integrative diagnostics; lipid profile; metabolomics; oral health; systemic inflammation.

Figure 1

The systemic consequences of long-term hospitalization affecting the oral–gut microbiota axis. Prolonged hospitalization involves multiple systemic stressors, such as inactivity, antibiotic exposure, tube feeding, and psychological stress. These factors disrupt the balance of oral and gut microbiota, leading to dysbiosis and altered production of microbial metabolites, including trimethylamine N-oxide (TMAO), short-chain fatty acids (SCFAs), and lipopolysaccharides (LPSs). The resulting pro-inflammatory and proatherogenic environment contributes to systemic inflammation, cardiovascular dysfunction, cognitive impairment, and lipid imbalance, ultimately accelerating cardiac deterioration.

Figure 2

Systemic interactions in long-term hospitalized cardiac patients.