Comparison of Archival Angiographic Findings in Patients Later Developing Acute Coronary Syndrome or Stable Angina

Acute coronary syndrome (ACS) can develop in patients with mildly to moderately stenotic lesions. However, the angiographic characteristics of lesions in patients who will later develop ACS have not been systematically investigated. For this reason, we examined the earlier angiographic findings of such patients in a retrospective study. The study population consisted of 45 consecutive ACS and 45 stable angina (SA) patients who require revascularization. All of them had received cardiac catheterization within 5 years prior to onset, for different masons. The detailed parameters of the earlier coronary angiographies at the culprit site the whole culprit vessel, and all three vessels were compared between the two groups. Mild-to-moderate stenosis was present exclusively at the culprit site in the earlier angiographies, both in ACS and SA patients. Lesions associated with ACS progression were significantly shorter in length than those associated with SA progression (11.5 +/- 5.5 versus 16.1 +/- 10.5 mm, P = 0.02) and were more eccentric (eccentricity index: 0.5 +/- 0.3 versus 0.7 +/- 0.3, P = 0.04). Percent diameter stenosis was similar (42.2 +/- 14.5 versus 44.0 +/- 13.8%, P = 0.5). The mean grading scores for plaque extension and size (1-3) were significantly lower in ACS than in SA (1.4 +/- 0.6 versus 1.8 +/- 0.6, P = 0.01, and 1.3 +/- 0.6 versus 1.7 +/- 0.7, P = 0.01, respectively). Residual SYNTAX scores were significantly lower in ACS (12.5 +/- 7.4 versus 16.4 +/- 8.6, P = 0.03). Despite equivalent degrees of stenosis in previous angiographies, ACS occurred more frequently in patients with more focal and eccentric lesions but with less diseased coronary arteries than SA.