ULTRASOUND MORPHOLOGY CLASSIFICATION OF THE ARTERIAL-WALL AND CARDIOVASCULAR EVENTS IN A 6-YEAR FOLLOW-UP-STUDY

A 6-year follow-up based on an arterial morphology classification defi ned with an ultrasound assessment of carotid and femoral artery bifurc ations was conducted on 2322 asymptomatic subjects. Four morphology cl asses were considered. When 2000 subjects (86% of total subjects; 1124 males, 876 females) completed a 6-year follow-up, the study was termi nated. At 6 years, no cardiovascular events were observed in subjects who were in class I (80.05% of the population sample) at inclusion; th ere were 69 events in classes II, III and IV (19.95% of the population ; incidence, 17.3%); 59 events,including the five deaths, occurred in classes III and IV (10.85% of the population), producing an event inci dence of 27.2%. The increased event rate in classes II, III, and IV wa s significant (log-rank test; P<.05, P<.025, and P<.025, respectively) . Thus, the arterial morphology classification identified 19.95% of th e population (subjects in classes II, III, and IV in which all events occurred. There was a higher (P<.05) rate of progression of altered ar terial morphology in 6 years in classes III (26.5% of subjects progres sed) and IV (41.9% progressed) than in classes I and II. The total num ber of cigarette-years was higher (P<.05) in classes II, III, and IV t han in class I. In conclusion, the ultrasound-based arterial classific ation was useful in selecting from the population sample 80.05% of sub jects (class I) who remained event-free for 6 years. All events occurr ed in class II, III, and IV subjects (19.95%), and ail five deaths (0. 25% of the population) occurred in classes III and IV (10.85% of the s ample).