Results of a Community-Based Coronary CT Angiography Screening in Asymptomatic Adults With Cardiovascular Risk Factors: The Broward County Heart Project

Heart disease remains the leading cause of death in the United States, often striking people who feel perfectly healthy. The danger lies in the silence of the disease; arteries can become clogged with fatty deposits, known as plaque, for decades before causing a heart attack or chest pain. Traditional risk calculators estimate a person's chance of having this problem based on factors like age, blood pressure, and smoking history, but these estimates cannot see the actual blockages inside the body. To look directly at the arteries, doctors use a specialized X-ray scan called a coronary computed tomography angiography, or CCTA. This test creates a detailed 3D map of the heart's blood vessels, revealing whether plaque is present and if it is narrowing the flow of blood. While these scans are standard for patients with symptoms, their value in checking large groups of people who feel fine has been less clear.

In Florida, a county-funded initiative called the Broward County Heart Project set out to test this idea on a massive scale. From May 2023 through September 2025, the program offered free heart scans to thousands of residents who had insurance and at least one risk factor for heart disease, such as high blood pressure, diabetes, or a family history of heart trouble. The goal was to see how many asymptomatic adults actually had hidden heart disease and to understand how these findings varied across different groups of people and neighborhoods. The project screened more than 7,000 adults between the ages of 45 and 70 at six different hospitals, providing a rare glimpse into the hidden heart health of a diverse community.

The results revealed that hidden heart disease is far more common than many might expect. Among the 7,135 participants who completed the screening, more than half—specifically 56.8 percent—had some form of abnormality in their heart arteries. The researchers categorized the findings into three groups: normal, abnormal, and very abnormal. While 43.2 percent of the scans showed no issues, 45.4 percent showed abnormal results that required follow-up, and 11.4 percent showed very abnormal results, indicating significant blockages or severe disease. This means that for every two people who walked into the program feeling fine, one was found to have a serious underlying condition that they were unaware of.

The likelihood of finding these hidden problems changed dramatically depending on a person's age and sex. The proportion of people with abnormal results rose steadily as participants got older. Among those aged 45 to 55, about 39 percent had abnormal findings. By the time participants reached their late sixties, that number jumped to nearly 74 percent, and for those 71 and older, it reached 78.5 percent. Men were also significantly more likely to have abnormal results than women. In this group, nearly 69 percent of men had abnormal or very abnormal findings, compared to just 40 percent of women. These patterns align with what doctors already know about how heart disease develops, showing that the risk accumulates with time and affects men more frequently in this age group.

The study also uncovered important differences based on race and ethnicity, which were not what the program organizers might have initially expected. Black participants had lower rates of abnormal results compared to White participants. While 58.6 percent of White participants had abnormal findings, only 38.9 percent of Black participants did. Similarly, Hispanic participants had lower rates of abnormal results than non-Hispanic participants. The researchers noted that these differences persisted even when they looked at the data from each hospital separately, suggesting the pattern was consistent across the region. However, the study authors cautioned that these findings do not mean Black or Hispanic residents are at lower risk overall; rather, the specific group of people who signed up for the screening might have differed in ways the study could not fully measure, such as their specific risk factor profiles or access to prior care.

One of the most intriguing aspects of the study was how the results varied depending on where the participants received their scans. The program operated across four different health systems, and the rate of abnormal findings ranged widely between them. At one hospital system, 60.3 percent of participants had abnormal results, while at another, the rate was only 39.5 percent. The researchers could not explain this gap with the data they had. It might be due to differences in the types of people who were referred to each hospital, or it could reflect subtle differences in how the scans were read or classified by the medical teams at each location. This variation suggests that where a person lives and which hospital they visit could influence whether they are told they have heart disease, even within the same county.

The program also looked at whether specific neighborhoods, identified by their ZIP codes, had higher concentrations of heart disease. The administrators had hoped that targeting areas with high risk would yield more positive results, but the data did not support this. The variation in abnormal findings across the 50 most active ZIP codes was no greater than what one would expect by random chance. This suggests that simply knowing a person's neighborhood is not enough to predict who has hidden heart disease; the risk is spread out in a way that does not cluster neatly in specific geographic pockets.

Despite the high number of people found to have heart disease, the study highlighted a significant gap in who actually participated. The program reached over 7,000 people, but the group did not fully reflect the diversity of Broward County. Women, Black residents, and Hispanic residents were underrepresented among the participants compared to the county's overall population. This suggests that the current method of reaching people—relying on doctors to refer patients and word-of-mouth—may not be effective enough to engage the entire community. To truly screen the population, the program may need to find new ways to connect with women and minority communities who are currently missing from the screening process.

Ultimately, this large-scale screening effort demonstrated that a county-funded program can successfully identify hidden heart disease in a vast number of people who would otherwise remain unaware of their condition. More than half of the screened adults had abnormalities that required medical attention, and the findings were strongly linked to age and sex. While the study did not measure whether these screenings ultimately saved lives or prevented heart attacks, it provided a clear picture of the scale of the problem. By finding these silent diseases, the program offered a chance to shift local healthcare from treating advanced emergencies to preventing them, though the authors noted that whether this approach improves long-term outcomes remains to be seen. The work serves as a powerful reminder that for many, the heart disease that kills is already present long before the first symptom appears.