Konstantinos Toutouzas, Maria Riga, Antonios Karanasos, Eleftherios Tsiamis, Andreas Synetos, Maria Drakopoulou, Chrysoula Patsa, Georgia Triantafyllou, Aris Androulakis, Christodoulos Stefanadis 1st Department of Cardiology, University of Athens, Hippokration Hospital, Athens, Greece
No conflicts of interest to disclose
Plaque rupture was the cause of 76% of SCD Severe luminal narrowing was the cause of SCD in 24% of cases Falk E,,Fuster V. Coronary plaque disruption. Circulation 1995;92:657 671
Virmani R, et al., JACC Oct 2009 Rupture (n=65) Erosion (n=50) p value Stenosis (%) 77.1±13.8 71.3±14.9 0.02 Necrotic core area (%) 38.3 ± 23.4 18.3 24.4 < 0.0001 Plaque burden 231 ± 67 190 ± 72 0.008 Macrophages (%) 3.44 ± 2.77 2.53 ± 2.65 0.03 Male gender (%) 89 74 0.008
Finding OCT (n=30) CAS (n=30) IVUS (n=30) Rupture 22 (73%) 14 (47%) 12 (40%) 0,021 Erosion 7 (23%) 1 (3%) 0 0,003 Thrombus 30 (100%) 30 (100%) 10 (33%) <0,001 p Kubo et al, JACC 2007
Gonzalo et al, IJC 2008 GS IVUS IVUS RFD OCT IV MR Axial resolution (μm) 100-150 100-150 10-20 200 Probe size (mm) 1.1 1.1 0.4 1.8 Penetration depth 4-8 mm 4-8 mm 1.5-2 mm 200 μm Vessel occlusion No No No/Yes Yes Morphological information Yes Yes Yes No Lipid identification + +++ ++ +++ Thin cap detection + + +++ - Remodelling +++ +++ + - Inflammation - - + -
Non-culprit lipidrich plaque with thick cap Napkin ring significant lesion Red thrombus MLS - white thrombus Toutouzas et al, Heart 2010 July Plaque rupture TCFA
The aim of the study was to provide a morphologic description of ruptured culprit lesion in acute coronary syndromes by optical coherence tomography.
Eighty four consecutive patients with STEMI and NSTEMI were included Coronary angiography was performed within 24 hours after symptom onset in NSTEMI and immediately before angioplasty in STEMI patients In patients with TIMI flow 0, manual thrombus aspiration was performed. All culprit lesions were investigated by OCT. Patients in whom lesion assessment was not possible due to poor image quality, were excluded from the study
Presence of plaque rupture was recorded. Plaque rupture was defined as the consistent presence of fibrous cap discontinuity in 2 frames. Patients in whom plaque rupture was not identified by OCT were excluded from the study. Thrombus presence was recorded and lipid content was measured semi-quantitavely by measuring the arc of lipid in the cross section
Analysis of the rupture site was performed in the site with the greatest plaque disruption Cross sectional area (CSA) and minimum fibrous cap thickness (FCT) were measured at rupture site and at minimal lumen site Rupture length and the distance of rupture site from minimal lumen site were measured, by measuring the number of crosssections where fibrous cap discontinuity was detected, knowing the pullback speed of the catheter. The length of the missing fibrous cap was measured in each cross-section and the incidence of plaques ruptured at the shoulder of the plaque was calculated
From the study population of 84 patients, 6 (7.1%) were excluded from the study due to poor image quality. Of the 78 patients that were successfully visualized, we identified 55 (70.5%) patients with plaque rupture, which were used for analysis in the present study. The incidence of rupture was similar in the groups of STEMI and NSTEMI (71.4% versus 69.4%; p=ns).
Age (y) 59.0±11.7 Male gender 44 (80.0%) DM 18 (32.7%) Prior statin use 23 (41.8%) Hypertension 34(61.8%) NSTEMI 25 (45.4%) STEMI 30 (55.6%)
Plaque rupture characteristics Lipid content 1 5 (9.0%) 2 16 (29.1) 3 17 (30.9%) 4 17 (30.9%) Thrombus 44 (80.0%) Location of rupture Distal to the MLS 19 (34.5%) MLS 19 (34.5%) Proximal to the MLS 17 (30.9%) Rupture at shoulder 38 (69.1%)
Quantitative assessment Length of rupture Distance from MLS 2.35±1.58 mm 2.34±2.21 mm CSA of MLS 2.01±1.50mm 2 CSA of rupture site 4.02±2.34 mm 2 Length of missing fibrous cap Minimal cap thickness at rupture site Minimal cap thickness at MLS 0.55±0.28 mm 55±20 μm 95±50 μm
Paired comparison of cap thickness at the site of the minimal lumen and at the site of the rupture (p<0.001). Frequency distribution of cap thickness at the site of the rupture.
Use of thrombectomy in STEMI Acute imaging large thrombus burden
Rupture of the plaque in myocardial infarction usually occurs in sites different than the minimal lumen. Plaque rupture is more common in site without significant stenosis, but with thinner fibrous cap, measuring 90μm. This finding needs further investigation with larger in vivo studies in order to make the identical choice of stenting for treatment of the culprit ruptured plaque of pts with ACS.