Tracking Coronary Calcification by Using Dual-Section Spiral CT: A 3-Year Follow-up

PURPOSE: To investigate the accuracy of dual-section spiral computed tomography (CT) in tracking the progression of coronary calcification, as measured during a 3-year follow-up. MATERIALS AND METHODS: Two hundred forty-six patients with hypertension (mean age, 66 years +/- 6 [SD]) were preselected in accordance with the International Nifedipine Study Intervention as a Goal for Hypertension Therapy protocol. Subjects had no clinical coronary arterial disease prior to the study and no cardiovascular events during follow-up. All participants underwent baseline CT (3.2-mm section thickness; reconstruction increment, 1.5 mm) and follow-up CT after 3 years. Calcification progression was defined as any increase in total calcification score (TCS) and analyzed in accordance with five baseline TCS categories: 1-9, 10-35, 36-100, 101-250, and greater than 250. RESULTS: At baseline CT, 152 patients had a TCS greater than 0, and 106 (70%) showed progression after 3 years, while 94 had a baseline TCS of 0; of these, 26 (28%) showed progression (P: <.01 between groups). The mean TCS was significantly higher in each baseline TCS category after 3 years. The percentage increase was negatively correlated with baseline TCS (P: <.01) and ranged from 466% in the lowest category to 38% in the highest. CONCLUSION: Dual-section spiral CT depicts significant change in TCS over time and is useful in tracking calcified coronary atherosclerosis.