Nearly one in 10 heart attacks and strokes in England and Wales could be prevented if routine check-ups were better targeted, say researchers.
Currently, people aged 40 and over are eligible to have their heart health assessed every five years.
But UCL scientists say people at low risk are being checked too often while those considered at high risk are not checked often enough.
They say a personalised approach could save lives without costing any more.
Chances of a heart attack or stroke can be worked out by looking at risk factors such as blood pressure, cholesterol and blood-sugar levels, age, family history and whether the person smokes.
High-risk patients are told to change their lifestyle, and if that does not work they are offered statins to reduce "bad" cholesterol or drugs to lower blood pressure.
The researchers followed 7,000 people to see how long they spent in different risk categories.
The study, in the Lancet Public Health, showed:
- "Low-risk" patients took an average of nine years to reach "intermediate-low-risk"
- "Intermediate-low-risk" patients spent an average of seven years in this category; 90% went on to become "intermediate-high-risk"
- But within four years, 70% of "intermediate-high-risk" patients became "high-risk" and needed treatment
The researchers then simulated different ways of screening people depending on their heart-risk category.
For example, screening low-risk patients every seven years, intermediate-low every four years and intermediate-high every year cost the same as the current system.
How big an impact?
However, the targeted system would enable high-risk patients to be treated sooner and prevent 8% of heart attacks and strokes, say the researchers.
That would prevent 5,000 people a year in England and Wales having a potentially life-threatening heart attack or stroke.
Prof Mika Kivimaki, one of the researchers, said: "The key message is use individualised screening, not one-size-fits-all.
"I believe this will change because there is a tendency towards precision medicine and individualised treatment and prevention.
"I think this will be taken up in future and I hope it will happen sooner rather than later."
The next stage of the research would be to perform a clinical trial to see whether switching screening methods would actually make a difference.
Prof Sir Nilesh Samani, medical director at the British Heart Foundation, said: "While changing the frequency of heart-health check-ups based on a person's individual risk could potentially save lives and costs, it's easier said than done.
"An issue that is even more important to address is why so many people who could benefit from health checks are not getting them in the first place.
"If you know you're at higher risk of developing heart and circulatory disease, it's really important to attend regular health checks to help manage your risk factors to prevent problems later in life."
Follow James on Twitter.