[From the single vulnerable plaque, to the multiple complex coronary plaques. From their basis, to the modern therapeutic approach. A clinical reality in the spectrum of the acute coronary syndromes].

Contemporary clinical and laboratory data have challenged our classical concepts of the pathogenesis of the acute coronary syndromes [ACS]. Indeed, several independent lines of clinical evidence have supported that the critical stenoses cause only a fraction of the ACS. Acute myocardial infarction is believed to be caused by rupture of a vulnerable coronary-artery plaque that appears as a single lesion on angiography. However, plaque instability might be caused by pathophysiologic processes, such as inflammation, that exert adverse effects throughout the coronary vasculature and therefore result in multiple unstable lesions. Recent studies have demonstrated that ruptured or vulnerable plaques exist not only at the culprit lesion but also in the whole coronary artery in some ACS patients. It has also been reported that a ruptured plaque at the culprit lesion is associated with elevated C- reactive protein and other inflammatory markers, which indeed indicate a poor prognosis in patients with ACS. Also, multiple plaque rupture is associated with systemic inflammation, and patients with multiple plaque rupture can be expected to show a poor prognosis. Therefore some ACS patients [20-40%] may harbor multiple complex coronary plaques that are associated with adverse clinical outcomes. It should be accepted that this ACS population represent a part of the spectrum of the ACS, and in particular in this group of patients treatment should focus not only on the stabilization of the culprit site but also warrants a broader approach to systemic stabilization of the arteries. However, recurrent cardiovascular events in this population still remain unacceptably high, indicating that plaque rupture or vulnerability of multiple plaques is a current challenge in the management of ACS patients.