Author + information
- Roberta Montisci,
- Massimo Ruscazio,
- CInzia Soro,
- Cristina Cacace,
- Antonio Bracco,
- Giorgio Lai,
- Mauro Cadeddu,
- Raimondo Pirisi,
- Maria Letizia Lai,
- Gavino Faa and
- Luigi Meloni
The pathogenetic mechanism in ACS is the rupture of atherosclerotic plaque and less frequent an erosion of the endothelium. The entity of superimposed coronary thrombus formation seem to guide the clinical expression of the disease: if the thrombosis is completely occlusive the patients will undergo acute myocardial infarction with ST elevation (STEMI), but if it is not, the patient will present an unstable angina or an acute myocardial infarction without persistent ST elevation (NSTEMI). The aim of our study is to evaluate possible differences in the histopathologic characteristics of coronary thrombus in STEMI and NSTEMI.
We studied 89 non consecutive STEMI patients (mean age 58.9±12.3 years) and 14 NSTEMI patients (mean age 65.2±10.6). All STEMI had manual thrombus aspiration (TA) during primary percutaneous coronary intervention (PCI) within 6 hours from symptom onset. All NSTEMI had TA during PCI within 24 hours from symptom onset. The aspirated material was evaluated for thrombus and plaque components, and thrombus age was classified as fresh, lytic, and organized.
At angiography a completed occluded culprit necrosis vessel was found in 90% of STEMI and in 86% NSTEMI. In 89% and 80% of STEMI and NSTEMI the aspirated material was principally composed of thrombus, and only in 16% and 14%, respectively some plaque elements were identified. In 43% of 14 NSTEMI, the thrombus was organized or showed lytic changes compatible with an origin of days or weeks before the acute occlusive event, whereas non fresh thrombus was present only in 18% of STEMI (p<0.05).
Our study shows the high percentage of occlusive thrombosis in NSTEMI undergoing an early invasive procedure suggesting that the pathogenic difference between STEMI and NSTEMI may also depend on other factors apart from the presence of non-occlusive and occlusive thrombosis. Our data confirm that acute coronary occlusion may be preceded by episodes of silent plaque instability before the acute event in STEMI and NSTEMI. It is possible that in NSTEMI, thrombus grows more gradually before occlusion of the culprit vessel favoring an ischemic preconditioning which can explain the lower extent of myocardial damage.
Poster Sessions, Expo North
Sunday, March 10, 2013, 9:45 a.m.-10:30 a.m.
Session Title: Acute Coronary Syndromes: Basic III
Abstract Category: 2. Acute Coronary Syndromes: Basic
Presentation Number: 1213-189
- 2013 American College of Cardiology Foundation