The lesional state vector: a new approach to characterize atherosclerotic lesions

A new approach to study the atherosclerotic lesions (AL) applying a vectorial system is presented. The "lesional state vector" (LSV) is formed by using as vectors the three main types of AL, e.g. fatty streak, fibrous plaque and severe plaque (complicated and calcified considered together) as the coordinates. This vectorial representation is part of a biometric system described in 1982 by Carlevaro and Fernández-Britto, to characterize the AL in any vascular sector or group of patients. The LSV is a suitable tool to study the AL since it conserves all the information available as primary data and it is extremely useful for comparative studies applying different statistical techniques, including multivariate approaches. To demonstrate its advantage, we studied the coronary vessels (right, left anterior descending and left circumflex arteries), the cerebral arteries (circle of Willis) and the aorta (thoracic and abdominal segments) in 2,043 autopsies performed during 5 years (1981-1985). The patients were classified according to the primary cause of death, as high atherosclerotic (HAG) or low atherosclerotic groups (LAG), comprising 1,171 and 872 cases, respectively. Qualitative and quantitative gross analysis were done by a digitizer joined to a personal computer (NEC 9801, Japan). These data were processed on computer ES 1040, GDR. The statistical techniques applied (including the multivariate analysis) were those available in the Statistical Package for Social Sciences (SPSS). Applying the LSV to the arteries studied it was found that in the coronary arteries and in the circle of Willis, the severe plaque and the fibrous plaque played the most important roles, respectively. Graphic representation can make differentiation between HAG and LAG easy.(ABSTRACT TRUNCATED AT 250 WORDS)