The aim of the project is to evaluate demographic, clinical, and laboratory variations in patients with aortic stenosis treated with TAVI in different countries. Moreover, the study will evaluate interpopulation differences in aortic root anatomy based on computed tomography analysis.

Aortic stenosis represents the most common valvular heart disease in developed countries, with a significant epidemiologic increase related to the aging population. Currently, surgical and transcatheter interventions are the only therapeutic options, as pharmacotherapy is still insufficient in the disease management. Transcatheter aortic valve implantation is recommended in selected groups of patients and provides optimal short and long-term outcomes.

Racial and ethnic disparities in aortic stenosis prevalence, management, and outcomes of treatment have been postulated. Data on discrepancies in aortic stenosis characteristics in patients qualified for transcatheter aortic valve implantation across populations are lacking.

The current project will conduct the analysis in populations of patients with aortic stenosis qualified for transcatheter aortic valve implantation from different countries to reveal potential disparities in clinical characteristics and in requirements for variations in prostheses sizes.

This is a retrospective, multicentre, observational registry of patients with severe aortic stenosis qualified for transcatheter aortic valve implantation.

Inclusion criteria - each site will include consecutive 100 patients who underwent transcatheter aortic valve implantation between January and June 2025.

Exclusion criteria - active infection (chronic inflammatory disease or neoplasm is not an exclusion criterion, however, will be considered in the laboratory analysis)

Data concerning

• patients' demographics,
• clinical characteristics
• results of aortic root and aorta analyses by computed tomography
• echocardiography results
• results of common laboratory tests (blood morphology, inflammatory ratios of neutrophils, monocytes and platelets to lymphocytes, glomerular filtration rate, N-terminal prohormone of brain natriuretic peptide) obtained during the routine care in the pre-procedural period will be collected at each site.

Simple procedural results (inc. prosthesis type and size) and outcomes (survival, bleeding, vascular complications, and acute kidney injury) will be recorded.

Collected data will be compared between study populations.

Inclusion Criteria:

• Severe aortic stenosis qualified for TAVI

Exclusion Criteria:

• Active infection (chronic inflammatory disease or neoplasm is not an exclusion criterion, however, will be considered in the laboratory analysis)

All consecutive patients qualified for TAVI will be included in the analysis and compared in subpopulations.