Myocardial Infarction w/ ST-Segment Elevation Disease Summary

Overview

Myocardial infarction (MI) is death of cardiac myocytes (irreversible necrosis) caused by prolonged or severe myocardial ischemia, as stated in the Introduction section.

Cardiovascular disease remains the number one cause of mortality in Western countries, with acute coronary disease being the leading cause. A detailed discussion about the prevalence of acute myocardial infarction is in the Epidemiology section.

The Pathophysiology section states that acute myocardial infarction starts with the rupture of lipid-laden atherosclerotic coronary plaque, leading to platelet activation and aggregation at the site of injury. Thrombus formation, ischemia and myocardial necrosis in acute myocardial infarction are discussed in this section.

The etiologies of myocardial infarction, such as coronary artery spasm, coronary atherosclerosis and plaque ruptures are enumerated in the Etiology section.

The Risk Factors section lists the general, modifiable, and lifestyle risk factors for ST-elevation myocardial infarction.

Myocardial Infarction w ST-Segment Elevation_Disease Summary

History and Physical Examination

The Clinical Presentation section describes the characteristic chest discomfort and other accompanying symptoms in the evaluation of myocardial infarction.

Inquiry of the patient’s medical, social and family history is important in assessing cardiovascular risk factors, as stated in the History section. The Physical Examination section enumerates the expected findings in patients with myocardial infarction. 

Diagnosis

The Diagnosis or Diagnostic Criteria section features initial assessment in patients presenting with chest pain or discomfort and discussion on acute coronary syndrome with or without persistent ST-segment elevation.

Assessment of patients into low-, medium-, and high-risk is further discussed in the Screening section.

Discussions on electrocardiogram and confirmatory tests are in the Laboratory Tests and Ancillaries section. The Imaging section explains imaging studies that are helpful in the evaluation of patients with myocardial infarction.

Other diseases that can present with the same symptoms as myocardial infarction with ST-segment elevation that should be ruled out are listed in the Differential Diagnosis section.

Management

All patients with ischemic symptoms of ≤12 hours and persistent ST-segment elevation or new or presumed new LBBB should undergo early mechanical (percutaneous coronary intervention or PCI) or pharmacological (fibrinolytic) reperfusion therapy unless they have contraindications as stated in the Evaluation section. Indications and contraindications for percutaneous coronary intervention and intravenous fibrinolytic therapy in the management of ST-elevation myocardial infarction are discussed in this section.

The Pharmacological Therapy section discusses in detail the symptomatic, antiplatelet, thrombolytic, ancillary and statin therapy, including anticoagulants, angiotensin-converting-enzyme (ACE) inhibitors, angiotensin II antagonist, beta-blockers, aldosterone antagonists, nitrates, calcium antagonists, lipid-lowering medications, blood pressure control, and glucose control depending on whether the management is for acute care, inpatient treatment, or secondary prevention of myocardial infarction.

The Nonpharmacological Therapy section discusses risk factor management such as diet modification, increase in physical activity, weight management, smoking cessation, and moderate alcohol consumption. Educating the patients and their family about cardiovascular disease and measures to reduce the risk of subsequent cardiac events and cardiac rehabilitation are also discussed in this section.

Coronary angiography, percutaneous coronary intervention (PCI) and coronary artery bypass graft (CABG) in the management of myocardial infarction are in the Surgery section.