Plaque ruptures in stable angina pectoris compared with acute coronary syndrome.

BACKGROUND

Plaque rupture is more frequently observed in patients with acute coronary syndrome (ACS) rather than in patients with stable angina pectoris (SAP). Consequently, studies regarding plaque rupture, which occurred in SAP patients, are rare. Therefore, we evaluated the frequency and axial location of plaque ruptures in SAP patients and compared them with those in ACS patients.

METHODS

Three hundred ninety-two patients (231 ACS and 161 SAP patients) who were scheduled for coronary intervention underwent three-vessel intravascular ultrasound (IVUS) study. IVUS criteria for plaque rupture were a plaque contained a cavity that communicated with the lumen with an overlying residual fibrous cap fragment. Using motorized IVUS transducer pullback in all three coronary arteries, the distance between each coronary plaque rupture segment and the respective coronary ostium was measured.

RESULTS

Plaque ruptures were detected in 206 of 392 patients who underwent three-vessel intravascular ultrasound examination. At least one plaque rupture in any coronary artery was noted in 48 (30%) SAP and 158 (68%) ACS patients (p<0.001). In both ACS and SAP patients, plaque ruptures were clustered mainly in the proximal segments of the left anterior descending artery and in the proximal and distal segments of the right coronary artery.

CONCLUSIONS

At least one plaque rupture in any coronary artery was noted in 30% of SAP patients. Like in ACS patients, plaque ruptures were clustered mainly in the proximal segments of the left anterior descending artery and in the proximal and distal segments of the right coronary artery in SAP patients.