What is the frequency and what are the risk factors for the progression of coronary atherosclerosis in patients with existing coronary artery obstruction?
Coronary atherosclerosis progression is common, increases with time, and appears more frequent in patients younger than 50 years, without significant correlation to traditional risk factors measured at initial catheterization.
Two hundred sixty-two patients with 50% or greater obstruction of at least one coronary artery on the initial study underwent recatheterization 2-182 months later and were evaluated for progressive arterial changes. Progression was considered present if (1) a change from less than total obstruction to total obstruction occurred in any vessel; (2) a change from 70% or less to 90% or more occurred in any vessel; (3) a change from 30% or less to 50% or more occurred in any vessel not initially obstructed by 50%; or (4) a 20% or more increase in obstruction was noted in any vessel already narrowed 50% or more. Of the 262 patients, 116 of 238 men (49%) and 12 of 24 women (50%) met the criteria for progression. Risk factors determined at the time of the initial catheterization in patients who met the criteria for progression were compared with risk factors in patients who did not. No significant difference could be found between the groups in relation to family history, blood pressure, diabetes, smoking habits, weight, cholesterol levels, triglyceride values, initial ECG and initial catheterization findings. The frequency of detecting progressive arterial changes tended to increase as the interval between studies increased (p less than 0.001). The frequency of multiple vessel progression increased as the interval between studies increased. Progression was more frequent in patients younger than 50 years than it was in patients 50 years and older.
Kramer et al. (Sun,) studied this question.