Impact of Plaque Rupture Detected by Optical Coherence Tomography on Transmural Extent of Infarction After Successful Stenting in ST-Segment Elevation Acute Myocardial Infarction.

Objectives: The aim of the present study was to investigate the association between plaque rupture (PR) assessed by optical coherence tomography (OCT), and the transmural extent of infarction (TEI) assessed by contrast-enhanced cardiac magnetic resonance imaging (CE-CMR) in ST-segment elevation myocardial infarction (STEMI) patients after primary percutaneous coronary intervention (PCI).

Background: PR is associated with larger infarct size as assessed by cardiac enzymes in STEMI patients. CE-CMR is a favorable method to assess TEI, which can predict the prognosis of STEMI patients.

Methods: First, STEMI patients with primary PCI within 12 h after onset were enrolled and divided into 2 groups according to presence (n = 71) or absence (n = 32) of PR at the culprit lesion as assessed by pre-intervention OCT. CE-CMR was performed at 1 week after primary PCI.

Results: The frequency of no-reflow phenomenon (37% vs. 16%; p = 0.032) and distal embolization (24% vs. 6%; p = 0.032) was significantly higher in the rupture group compared with the non-rupture group. TEI grade was significantly greater in the rupture group (28% vs. 15% in grade 3 and 45% vs. 13% in grade 4; p < 0.001). Microvascular obstruction was more frequently seen in the rupture group (39% vs. 19%; p = 0.039). Multivariate analysis identified PR (odds ratio: 6.60, 95% confidence interval: 2.19 to 21.69; p < 0.001) and no statin use before admission (odds ratio: 3.37, 95% confidence interval: 1.06 to 11.19; p = 0.039) as independent predictors of TEI grade 3 or 4.

Conclusions: PR as assessed by OCT is associated with greater TEI as assessed by CE-CMR in STEMI patients after primary PCI.