Koronare Herzkrankheit und akutes Koronarsyndrom

Abundant data link hypercholesterolaemia to atherogenesis. However, only recently have we appreciated that inflammatory mechanisms couple dyslipidaemia to atheroma formation. Leukocyte recruitment and expression of pro-inflammatory cytokines characterize early atherogenesis, and malfunction of inflammatory mediators mutes atheroma formation in mice. Moreover, inflammatory pathways promote thrombosis, a late and dreaded complication of atherosclerosis responsible for myocardial infarctions and most strokes. The new appreciation of the role of inflammation in atherosclerosis provides a mechanistic framework for understanding the clinical benefits of lipid-lowering therapies. Identifying the triggers for inflammation and unravelling the details of inflammatory pathways may eventually furnish new therapeutic targets.

During the past decade, our understanding of the pathophysiology of coronary artery disease (CAD) has undergone a remarkable evolution. We review here how these advances have altered our concepts of and clinical approaches to both the chronic and acute phases of CAD. Previously considered a cholesterol storage disease, we currently view atherosclerosis as an inflammatory disorder. The appreciation of arterial remodeling (compensatory enlargement) has expanded attention beyond stenoses evident by angiography to encompass the biology of nonstenotic plaques. Revascularization effectively relieves ischemia, but we now recognize the need to attend to nonobstructive lesions as well. Aggressive management of modifiable risk factors reduces cardiovascular events and should accompany appropriate revascularization. We now recognize that disruption of plaques that may not produce critical stenoses causes many acute coronary syndromes (ACS). The disrupted plaque represents a "solid-state" stimulus to thrombosis. Alterations in circulating prothrombotic or antifibrinolytic mediators in the "fluid phase" of the blood can also predispose toward ACS. Recent results have established the multiplicity of "high-risk" plaques and the widespread nature of inflammation in patients prone to develop ACS. These findings challenge our traditional view of coronary atherosclerosis as a segmental or localized disease. Thus, treatment of ACS should involve 2 overlapping phases: first, addressing the culprit lesion, and second, aiming at rapid "stabilization" of other plaques that may produce recurrent events. The concept of "interventional cardiology" must expand beyond mechanical revascularization to embrace preventive interventions that forestall future events.

Percutaneous coronary intervention (PCI) involving drug-eluting stents is increasingly used to treat complex coronary artery disease, although coronary-artery bypass grafting (CABG) has been the treatment of choice historically. Our trial compared PCI and CABG for treating patients with previously untreated three-vessel or left main coronary artery disease (or both). We randomly assigned 1800 patients with three-vessel or left main coronary artery disease to undergo CABG or PCI (in a 1:1 ratio). For all these patients, the local cardiac surgeon and interventional cardiologist determined that equivalent anatomical revascularization could be achieved with either treatment. A noninferiority comparison of the two groups was performed for the primary end point--a major adverse cardiac or cerebrovascular event (i.e., death from any cause, stroke, myocardial infarction, or repeat revascularization) during the 12-month period after randomization. Patients for whom only one of the two treatment options would be beneficial, because of anatomical features or clinical conditions, were entered into a parallel, nested CABG or PCI registry. Most of the preoperative characteristics were similar in the two groups. Rates of major adverse cardiac or cerebrovascular events at 12 months were significantly higher in the PCI group (17.8%, vs. 12.4% for CABG; P=0.002), in large part because of an increased rate of repeat revascularization (13.5% vs. 5.9%, P<0.001); as a result, the criterion for noninferiority was not met. At 12 months, the rates of death and myocardial infarction were similar between the two groups; stroke was significantly more likely to occur with CABG (2.2%, vs. 0.6% with PCI; P=0.003). CABG remains the standard of care for patients with three-vessel or left main coronary artery disease, since the use of CABG, as compared with PCI, resulted in lower rates of the combined end point of major adverse cardiac or cerebrovascular events at 1 year. (ClinicalTrials.gov number, NCT00114972.) 2009 Massachusetts Medical Society