Despite significant progress in cardiac surgery, postoperative complications remain a serious challenge. Recent findings indicate that the gut microbiota plays an important role in regulating systemic inflammation and influencing clinical outcomes. According to the concept of the “gut-heart axis,” an imbalance in the microbiota may increase patients’ susceptibility to complications such as pneumonia, sepsis, wound infection, acute kidney injury (AKI), and delirium.

This prospective cohort study aims to determine the association between the gut microbiota and postoperative complications in patients undergoing coronary artery bypass grafting and/or valve replacement in Georgia. The study will enroll 80 adult patients at the Ingorokva High-Tech Clinic. Stool samples will be collected preoperatively and on days 5–7 postoperatively. Microbiota analysis will be conducted at the Richard Lugar Center for Public Health Research using 16S rRNA genomic sequencing. Clinical and laboratory data will be integrated with microbiome data to predict complications.

The project is interdisciplinary and combines clinical cardiology, microbiology, epidemiology, and bioinformatics. The project will contribute to the development of local research capabilities, the strengthening of personalized medicine, and the creation of microbiota-based risk assessment tools.

The results of the study will be disseminated in peer-reviewed journals, scientific conferences, and with relevant stakeholders. The results can influence clinical protocols, improve patient recovery, and reduce healthcare-associated infections, which will contribute to the development of the healthcare and biomedical sectors in Georgia.

Project Objective
The aim of the study is to determine the relationship between gut microbiota and postoperative complications in patients undergoing coronary artery bypass grafting and/or valve replacement in Georgia.

Project Objectives
Task 1: Study of changes in gut microbiota: Within 12 months from the start of the project, in 50 adult patients undergoing coronary artery bypass grafting and/or valve replacement at the Ingorokva High-Tech Clinic, we will study changes in the composition of the gut microbiota before surgery and on the 5th–7th day after surgery, using the 16S rRNA genomic sequencing method.

Task 2: Assessment of associations between microbiota and complications:
During the project, we will collect clinical and laboratory data and analyze the characteristics and Association between postoperative complications (surgical wound infection, sepsis, pneumonia, acute kidney injury, delirium and mortality), using statistical models. 

Task 3: Analysis and dissemination of results: An integrated data analysis (clinical + microbiome data) will be conducted and the results will be disseminated to relevant stakeholders to facilitate the development of microbiota-based risk assessment tools in Georgia. No later than 6 months after the completion of the project, at least 1 scientific article will be prepared for publication in international peer-reviewed journals, and the results will be presented at at least 1 international conference.  
 

Results for the development of science/field: The study will create new evidence on the relationship between the intestinal microbiota and postoperative complications in cardiac surgery patients. The findings will play an important role in the development of personalized medicine, will contribute to the creation of prognostic models and diagnostic tools based on microbiota, and thus strengthen the field of biomedicine in Georgia. This type of research is being conducted for the first time in Georgia. The results will also have an educational effect, they will be integrated into medical training programs and will strengthen the academic infrastructure.
Impact and benefits for target groups: The expected benefits for patients are related to the reduction of postoperative complications and improvement of the quality of medical care. For the healthcare system, the study will contribute to the implementation of more effective preventive strategies and cost reduction. For young researchers and doctoral students, the project represents a unique opportunity to gain practical experience in modern research methods. At the same time, the research results will also benefit policymakers by providing evidence-based, reliable information for planning clinical practice and healthcare policy.