Abstract Body (Do not enter title and authors here): Background:
Awareness of health disparity have grown, however certain demographic groups particularly racial minorities, continue to be underrepresented. This limits the generalizability of trial findings and contributes to inequality in care, potentially affecting cardiovascular outcomes. We aim to address these gaps by examining racial distribution in Acute Myocardial Infarction (AMI), Transcatheter Aortic Valve Replacement (TAVR), and Peripheral Vascular Disease (PVD) conducted in the United States and the United Kingdom over the past decade.

Methods:
A systematic review was conducted of clinical trials registered on ClinicalTrials.gov between January 1, 2015, and May 1, 2025, across three cardiovascular domains: TAVR, AMI and PVD. Data on participant demographics was extracted from baseline characteristics and aggregated. Proportion of participants were analyzed for racial distribution across the three cardiovascular conditions in both countries using R 4.4.1.

Results:
Analysis included 149,796 participants. White participants were most represented across all conditions (54.72% in US AMI to 83.73% in UK PVD). Black or African American representation was low, particularly in AMI (US: 0.80%, UK: 1.54%) and TAVR (US: 1.81%, UK: 0.63%), but higher in US PVD (10.19%). Asian participants were more frequent in UK trials (AMI: 19.89%) than US (4.49%). American Indian or Alaska Native, Native Hawaiian, and multiracial individuals comprised less than 3% overall. A substantial portion was "Other/Unknown/Not Reported," especially in US trials (AMI: 39.93%, TAVR: 29.18%) and UK TAVR (33.28%), indicating significant reporting gaps

Conclusion:
Our analysis reveals persistent disparities in racial representation across cardiovascular clinical trials conducted in the US and UK between 2015 and 2025. Minority racial groups remain consistently underrepresented, and the high proportion of unreported demographic data further compromises the inclusivity and generalizability of these studies.
Despite the presence of regulatory frameworks aimed at promoting equitable participation, such as the NIH Revitalization Act of 1993 and FDA diversity guidance in the United States, and the UK Equality Act 2010, a clear gap persists between policy and practice. Bridging this requires strengthening accountability for diversity benchmarks, standardizing race and ethnicity data reporting, and enhancing access through community-based recruitment and culturally responsive outreach.