COMPARISON OF CORONARY CALCIUM IN STABLE ANGINA-PECTORIS AND IN FIRSTACUTE MYOCARDIAL-INFARCTION UTILIZING DOUBLE-HELICAL COMPUTERIZED-TOMOGRAPHY

Although coronary calcium is invariably associated with atherosclerosi s, its role in the pathogenesis of acute and chronic coronary syndrome s remains unclear. Utilizing double helical computerized tomography we evaluated the coronary calcium patterns in 149 patients: 47 with chro nic stable angina (SAP) compared with 102 patients surviving a first a cute myocardial infarction (AMI). Prevalence of coronary calcium was 8 1% among the AMI patients and 100% in the stable angina patients. The 547 calcific lesions identified in the AMI patients and the 1,242 lesi ons in the stable angina patients were categorized into 3 groups accor ding to their extent: mild, intermediate, and extensive. The age-adjus ted percentages of the highest level of calcification among AMI versus stable angina patients were: mild 18% vs 3%, intermediate 49% vs 18%, and extensive lesions 33% vs 79%, respectively (p < 0.01). In the AMI group, 73 culprit arteries were identified: 16 (22%) had no calcium d etected, whereas 30 (41%) had mild lesions, 20 (27%) had intermediate forms, and only 7 (10%) had extensive lesions. The age-adjusted mean o f the natural logarithm transformation of total calcium scores +1 was significantly lower in patients with AMI than in those with SAP (4.1 ( 95% confidence interval 3.7 to 4.4) vs 5.3 [95% confidence interval 4. 8 to 5.8]). Thus, double helical computerized tomography demonstrates that extensive calcium characterizes the coronary arteries of patients with chronic stable angina, whereas a first AMI most often occurs in mildly calcified or noncalcified culprit arteries. (C) 1998 by Excerpt a Medico, Inc.