Natural History and Topographic Pattern of Progression of Coronary Calcification in Symptomatic Patients

Abstract

Abstract-Electron-beam CT may assess the progression of coronary atherosclerosis by visualizing changes in calcification. The present investigation analyzes (1) the rate of progression of calcification in symptomatic patients, (2) the topographic pattern, and (3) the influence of baseline plaque burden and risk factors. Progression of calcification during a mean (median) interval of 18 (15) months was measured in 102 symptomatic outpatients (aged 59Ϯ9 years, 80% male) with calcification. In 4 patient groups with a baseline total score (Agatston criteria) of 1 to 30, Ͼ30 to 100, Ͼ100 to 400, and Ͼ400, the median was 3.1, 26.1, 58.9, and 109.7, respectively, for absolute annual progression of the score (PϽ0.05) and 57%, 49%, 32%, and 15%, respectively, for relative progression (PϽ0.05). On the coronary segmental level, changes were largely restricted to typical predilection sites of coronary atherosclerosis. The presence of angiographically defined coronary narrowing influenced absolute, but not relative, progression. Of the risk factors, only low density lipoprotein cholesterol levels showed a trend, although not significant, for predicting progression. These data indicate that baseline plaque burden determines the rate of progression of calcification. This appears to be a coronary systemic process, reflecting the natural history of coronary atherosclerosis. Key Words: progression Ⅲ coronary atherosclerosis Ⅲ calcium Ⅲ electron-beam CT Ⅲ coronary artery disease E lectron-beam CT (EBCT) has been used in serial studies to determine the progression of coronary calcified plaque disease. [1][2][3][4][5][6] The natural rate of progression of calcification has been described in healthy subjects in a community setting. 4 It has been suggested that in asymptomatic high-risk patients, the influence of treating elevated lipid levels on the progression of coronary atherosclerotic disease can be evaluated by use of EBCT. 3,5 If these reports are taken into consideration, EBCT may be of value in assessing the treatment of symptomatic patients. However, little is known about the rate of progression to be expected in symptomatic patients with modern pharmacological therapy. The progression of calcification may vary substantially between patients with or without established coronary artery disease (CAD) and may depend on the baseline amount of calcification. 6 As calcification develops, the pattern of distribution among the major coronary arteries and the coronary segments has not been clarified. Only the changes in the overall amount of calcification have previously been reported. It was the aim of the present investigation (1) to analyze the rate of progression of calcification in symptomatic patients with modern treatment, (2) to establish the topographic pattern of progression, and (3) to determine the relationship of EBCT-derived and angiographic coronary findings and of risk factors with the rate of progression. Methods PatientsOutpatients followed in the Cardiology Department of the University Clinic Essen because of known...

Influence of Lipid-Lowering Therapy on the Progression of Coronary Artery Calcification

“…4 -6 The presence and extent of coronary calcifications can be assessed noninvasively using fast CT techniques, such as electron beam tomography (EBT) 7,8 or multislice CT. 9,10 Several investigations have shown that the quantity of coronary calcium measured by CT progresses over time. 9,[11][12][13][14][15] Consistently, an increase in coronary calcium progression with increasing baseline calcium scores has been observed. 9,14,15 In the only investigation that included asymptomatic, randomly selected individuals, Maher et al 11 observed a 24% mean annual increase in the amount of coronary calcification when quantified using the Agatston score.…”

“…9,[11][12][13][14][15] Consistently, an increase in coronary calcium progression with increasing baseline calcium scores has been observed. 9,14,15 In the only investigation that included asymptomatic, randomly selected individuals, Maher et al 11 observed a 24% mean annual increase in the amount of coronary calcification when quantified using the Agatston score.…”

“…The median annualized change of the calcified volume observed during the treatment period was Ϫ3.4%. Although several previous reports investigated the progression of coronary calcifications 8,9,[11][12][13][14][15] and 2 of these studies retrospectively identified lipid-lowering treatment to be associated with reduced progression of coronary calcifications, 12,13 our investigation is the first report that prospectively investigated the influence of lipid-lowering therapy on coronary calcium progression.…”

“…In their recent analysis, Schmermund et al 14 observed a moderate relationship between LDL cholesterol levels and the degree of progression of coronary calcification, whereas two other groups have observed an association of lipidlowering treatment and the rate of calcium progression in retrospective analyses. 12,13 So far, however, no prospective investigation has been published that could prove an effect of lipid-lowering drug treatment on the progression of coronary calcifications.…”

Vascular Calcification Mechanisms

“…Indeed, evidence for regression of coronary calcification in humans has also been obtained. In a study of 102 symptomatic patients with coronary calcification currently being treated with standard medications, 15% of patients showed evidence of regression on the basis of electron beam computed tomography calcium scores measured at baseline and approximately 6 mo later (60).…”