"Ultrasonic biopsy"--a non-invasive screening technique to evaluate the cardiovascular risk and to follow up the progression and the regression of arteriosclerosis.

To determine the prevalence of atherosclerotic plaques in different age groups, an ultrasound examination of carotid and femoral artery bifurcations was performed in 2000 asymptomatic subjects with an age range of 10-93. Subjects were graded into classes A-F according to vessel wall characteristics: A) normal wall (intima media and adventitia clearly separated); B) interface disruption; C) intima-media granulation; D) plaque without hemodynamic disturbance; E) stenosing plaque (no symptoms); F) plaque + stenosis + symptoms. Atherosclerotic changes were seen with increasing frequency with age. Subclinical lesions were commonest in the 70-79 age group and 30% of these subjects were in D-E classes. A cardiac stress test was performed on 204 subjects in the 50-59 age group. The incidence of ischemic events in this group was 57.6%, the majority of these occurred in subjects in classes D-E. In a four year follow-up of 424 subjects, less than 1.9% showed a significant change in their global score. However, 47 early atherosclerotic lesions were seen to progress and 18 to regress. Over four years, 15% developed cerebrovascular symptoms and 18% developed symptomatic peripheral vascular disease. All these patients were in D-E classes at the beginning of the study. Cardiovascular events also occurred with increasing frequency in classes C-E (A + B = 0, C = 5.7%, D = 12%, E = 39.3%). Mortality rate was 4.8%, all patients being in classes D-E. In conclusion, high resolution ultrasound may be used for an arterial "ultrasonic biopsy". This technique can detect early atherosclerotic changes and can predict the risk of occult cardiac disease and the risk of developing symptomatic disease.