Jyun Okuda

Relation between C-reactive protein levels on admission and pattern of acute myocardial infarction onset

The pathogenic mechanisms underling the onset of acute myocardial infarction (AMI) have not been fully clarified. Recent observations of inflammatory cell infiltration in unstable coronary plaques suggest that inflammation may play an important role in the pathogenesis of AMI. Plasma levels of C-reactive protein (CRP), a sensitive marker of inflammation, start to rise at least 6 hours after the onset of AMI. Therefore, CRP levels within the first 6 hours after the onset of AMI more likely reflect preexisting inflammatory activity rather than myocardial cell necrosis. We examined the relation between CRP levels on admission and the onset pattern of AMI to estimate the contribution of inflammation to the pathogenesis of AMI.

Percutaneous coronary intervention in ST-segment elevation myocardial infarction

Reperfusion therapy has dramatically reduced mortality from ST-segment elevation myocardial infarction (STEMI) during the past 30 years. Such therapy is thought to act primarily by promoting recanalization of the occluded coronary artery and reperfusion of the coronary microcirculation, thereby salvaging ischemic myocardium, reducing infarct size, and improving left ventricular function. Even when the ischemic myocardium has already become necrotic and myocardial salvage is not feasible, restoration of coronary blood flow can inhibit left ventricular remodeling, prevent fatal arrhythmias, and provide collateral circulation to other occluded vessels, thereby improving outcomes. To ensure maximal effectiveness, reperfusion therapy should be administered within 2–3 h after symptom onset at the latest; this applies to primary percutaneous coronary intervention (PCI) as well as fibrinolytic therapy [1] (Fig. 1). In this paper, we outline the current status of reperfusion therapy in Japan, focusing on catheter-based interventions in patients with STEMI. Reperfusion therapies for STEMI include fibrinolysis, primary PCI, and a combination of both treatments. Fibrinolysis is a simple procedure, but has a low rate of recanalization and high rates of recurrent ischemia including reinfarction and hemorrhagic complications. Many randomized clinical trials and meta-analyses have shown that primary PCI carefully performed without delay by skillful, experienced operators in well-equipped hospitals generally produces better outcomes than either fibrinolysis alone or a combination of fibrinolysis and primary PCI. In principle, primary PCI is indicated for all patients with STEMI who present within 12 h after the onset of symptoms [2, 3].