Abstract 15362: Impact of Morphological Characteristics of Ruptured Fibrous Cap Assessed by Optical Coherence Tomography on Creatinin Kinase Elevation in Acute Coronary Syndrome
Backgrounds: Plaque rupture has been reported as a major cause of acute coronary syndrome. Recent study suggested the association between the morphology of ruptured cap and clinical presentation.
Objectives: To investigate the relationship between ruptured cap morphology and myocardial damage represented by peak CK level.
Methods and Results: From a total of 157 patients with acute coronary syndrome (ACS), 67 lesions with disrupted fibrous cap from 67 patients were identified by pre-procedural OCT imaging and investigated in the present study (STEMI 45, NSTEMI 11, UAP 11). OCT analyses included thinnest cap thickness (CT), the type of a rupture site, longitudinal length of fibrous cap disruption (LL), aperture length of disrupted cap (AL), and ruptured cavity cross-sectional area (c-CSA). Rupture site was defined as center- or shoulder-type by the site of cap disruption. Location of rupture was classified into 3 types of proximal-type, distal-type, and mid-type according to longitudinal position of fibrous cap disruption to minimum lumen area site. Remodeling index (RI) and plaque area (PA) were determined by IVUS. Patients were classified into 2 groups by the median value of peak CPK (high-CPK and low-CPK), and morphological characteristics obtained by OCT and IVUS were compared between two groups. The median value of peak CPK was 1975 (IQR 506 - 3283) IU/L. There was no significant difference in age, gender, prevalence of risk factors, and lesion location between the two groups. In OCT analysis, center-type rupture tended to be frequent (75.8% and 55.9%, p=0.09) and distal-type rupture was significantly less frequent (6.5% and 23.5%, p<0.05) in high-CPK group than in low-CPK group. LL was significantly greater in high-CPK group (5.1±2.6mm and 3.4±2.5mm, p=0.01), whereas no significant difference was observed in CT, AL, and c-CSA. IVUS analyses showed greater PA in high-CPK group than in low-CPK group, whereas no significant difference was observed in RI. In multivariate analysis, LL and PA were predictors for high peak CPK level.
Conclusions: Longitudinal length of cap disruption and plaque area were independently associated with greater myocardial injury in ACS, whereas the type and location of cap disruption had modest relationship with CPK level.
- © 2011 by American Heart Association, Inc.