COMPARISON OF CORONARY ANGIOGRAPHIC FINDINGS IN ACUTE AND CHRONIC 1ST PRESENTATION OF ISCHEMIC-HEART-DISEASE

Background. It is generally assumed that the clinical manifestations of ischemic heart disease occur randomly on the same underlying pathological process. Therefore, coronary angiographic findings should be similar whether the first presentation of ischemic heart disease is acute myocardial infarction or uncomplicated chronic stable angina. Methods and Results. We studied 102 patients (men less-than-or-equal-to 60 years old, women less-than-or-equal-to 65 years old) presenting with either acute myocardial infarction as first manifestation of coronary artery disease with a concomitant coronary angiogram (55 patients; mean age, 50.2 years) or stable angina for at least 2 years with no history, ECG, or left ventriculographic evidence of any acute event and with an angiogram performed at least 2 years after initial symptoms (47 patients; mean age at symptom onset, 51.7 years). These angiograms were evaluated blindly for severity (number of vessels diseased, stenoses greater-than-or-equal-to 50%, occlusions), extent of disease (with an index derived by assigning a score of 0-3 per segment, depending on the proportion of lumen length irregularity and dividing the sum by the number of visualized segments), and pattern (discrete: three or fewer loci of disease never involving more than 50% of the length of any segment or diffuse: anything exceeding this). Patients with unheralded myocardial infarction had fewer vessels diseased, fewer stenoses and occlusions, and a lower extent index than those with uncomplicated stable angina (mean +/- SD of 1.3 +/- 0.8 versus 2.1 +/- 0.8, p < 0.001; 2.1 +/- 1.8 versus 3.9 +/- 1.8, p < 0.001; 0.6 +/- 0.6 versus 1.0 +/- 0.9, p < 0.02; and 0.6 +/- 0.5 versus 1.2 +/- 0.5, p < 0.001, respectively). A discrete pattern was present in 54.5% of patients with unheralded infarction and in only 8.5% of those with uncomplicated angina (p < 0.001). Conclusions. These very different angiographic findings suggest that unheralded acute myocardial infarction and uncomplicated chronic stable angina do not occur randomly on a common atherosclerotic background but rather that additional factors, such as a varying propensity to thrombosis, may predispose to one or the other of these two clinical syndromes.