What is plaque?
Plaque is a build-up in the inner wall of the arteries. It forms when LDL cholesterol becomes lodged in the vessel wall. The body responds with inflammation: immune cells take up the cholesterol, and over time a cap of connective tissue forms around this core.
- Slow growth: Plaque usually grows over years and decades without causing symptoms.
- Calcium comes later: Calcium only builds up in the plaque gradually. That is why people speak of “hardening of the arteries”, even though early plaque contains no calcium at all.
- The real risk: If a plaque ruptures, a blood clot forms at that spot and can suddenly block the artery. This is the most common cause of heart attacks and of many strokes. Even plaque that barely narrows the vessel can rupture.
57% already had plaque, without any symptoms.
- Age 18 to 29: 8.7% of men and 6.7% of women. Around 1 in 13 young adults is affected.
- Age 30 to 39: already 34.6% of men and 21.3% of women.
- Age 40 to 49: already 66% of men and 48% of women.
- Women catch up: In women, atherosclerosis starts 5 to 10 years later but rises particularly steeply around menopause.
- Rarely confined to the heart: At most 9.3% of men and 5.0% of women had plaque only in the coronary arteries. It usually also appears in other arteries, for example in the neck, where an ultrasound can show it without radiation.
Of 100 people over 40 with plaque, SCORE2 classified fewer than 2 as high risk.
- Even with plaque in several vascular regions, the calculator flagged only about 4 in 100.
- A calcium score of zero does not mean plaque-free: Among 30- to 39-year-olds with plaque in their coronary arteries, 42% of men and 48% of women had a calcium score of zero. Their plaque was still soft and visible only on a contrast-enhanced cardiac CT. The box below explains the difference.
- Still open: A large follow-up study starting in 2027 will test whether treatment guided by ultrasound or CT prevents more heart attacks.
Calcified or soft plaque: which test shows what?
Young plaque is still soft and consists mainly of cholesterol and connective tissue. It only calcifies over the years. This determines which test can detect it.
- Calcium score (cardiac CT without contrast): measures only the calcium in the coronary arteries. The scan takes a few minutes, needs no IV line and uses very little radiation. It cannot detect soft plaque, however. A calcium score of zero therefore does not rule out plaque, especially in younger people.
- Coronary CT angiography (cardiac CT with contrast): a contrast agent is given through a vein to make the inside of the coronary arteries visible. This also reveals soft, not yet calcified plaque and narrowings. With modern scanners, the radiation dose is low.
- Carotid ultrasound: no radiation and no contrast agent. It shows both soft and calcified plaque in these arteries. In the study, most people with plaque in the heart also had plaque in other arteries.
Which test makes sense for you depends on your age, risk profile and the clinical question. Learn more about coronary CT and carotid ultrasound.
Who should consider an assessment
The study does not yet support ultrasound screening for everyone. In our heart check-up, we determine whether a vascular assessment would help in your case.
An assessment can be worthwhile in these cases:
- Heart attack or stroke in a close relative at a younger age
- Raised LDL cholesterol or lipoprotein(a)
- Smoking, high blood pressure or diabetes
- Women going through menopause or who had high blood pressure during pregnancy (women’s cardiology)
- An “intermediate” risk score, when it is unclear whether treatment is needed
If plaque is found, this can change the decision about lowering cholesterol. If none is found, this often spares you unnecessary medication.
Source: Bundgaard H et al. Prevalence of Silent Atherosclerosis across Adult Life. N Engl J Med 2026. View study
