Acute coronary syndromes Ischemic heart disease

Coronary heart disease, acute coronary syndrome and angina pectoris are the leading cause of mortality in the United States. Annually, 451000 people die from these diseases, 800000 suffer acute MI and 156000 died from an MI, and many more are hospitalized due to an acute manifestation of ischemic heart disease. The personal, social and economic consequences are enormous, for 2008 they are estimated at 156.4 billion annually in the United States alone [31]. 

O Ischemic heart disease results from an imbalance between myocardial oxygen demand and oxygen supply that is most often due to coronary atherosclerosis. Common clinical manifestations of ischemic heart disease include chronic stable angina and the acute coronary syndromes of unstable angina, non-ST-segment elevation myocardial infarction, and ST-segment elevation myocardial infarction. 

The major goals for the treatment of ischemic heart disease are to prevent acute coronary syndromes and death, alleviate acute symptoms of myocardial ischemia, prevent recurrent symptoms of myocardial ischemia, and avoid or minimize adverse treatment effects. 

The term acute coronary syndrome (ACS) encompasses most of the patients defined so far in this chapter who present with unstable ischemic heart disease. Most of these syndromes occur in response to an acute event in the coronary artery when circulation to a region of the heart is obstructed. If the obstruction is high grade and persists, then necrosis usually ensues. Since necrosis takes some time to develop, it is apparent that therapy, including opening the blocked coronary artery in a timely fashion, often can prevent some of the death of myocardial tissue. These syndromes are usually, but not always, associated with chest discomfort. 

In the United States, approximately 700,000 patients suffer from an initial AMI annually and another 500,000 from a recurrent AMI. Coronary heart disease causes 20% of all deaths in the United States and cardiovascular diseases up to 38.5%. About 1.7 million patients are hospitalized each year in the United States with an acute coronary syndrome (ACS). Historically, most deaths caused by ischemic heart disease were acute, but as our therapeutic abfiities have increased, the disease is slowly becoming a more chronic one. When deaths occur acutely, they are caused by either... 

Clearly, coronary microembolization is a frequent event in ischemic heart disease, spontaneously in patients with unstable angina / acute coronary syndromes as well as artificially during coronary interventions with typical consequences, such as malignant arrhythmias and contractile dysfunction (Figure 7). The resulting microcirculatory impairment causes patchy microinfarction, and is often associated with coronary hyperemia at baseline and, conversely, transiently reduced coronary reserve. These obser-... 

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