Management of Myocardial Infarction – Reperfusion

The modern treatment of Myocardial Infarction relies heavily on the reperfusion therapy. Reperfusion therapy includes the usage of Thrombolytic therapy, Percutaneous coronary intervention, Coronary artery bypass surgery and Reperfusion dysrhythmia. Patients with suspected acute myocardial infarction and ST segment elevation (STEMI) are assumed to have an obstructive thrombosis in an epicardial coronary artery. These candidates  are treated for immediate reperfusion with thrombolytic therapy and percutaneous coronary intervention (PCI). When these therapies are unsuccessful, bypass surgery is performed. The PCI or medical management is preferred over the emergency bypass surgery for the treatment of an acute myocardial infarction (MI). The primary percutaneous coronary intervention is beneficial over thrombolytic therapy for the treatment of acute ST elevation myocardial infarction.

Individuals that do not have ST segment elevation are assumed that they are experiencing either non-ST segment elevation myocardial infarction (NSTEMI) or unstable angina (UA). These patients are given initial therapies and they are stabilized with antiplatelet drugs and anticoagulated. If the condition remains stable, they are offered late coronary angiography with consequent restoration of blood flow (revascularization). These patients can also be given non-invasive stress testing for determining if there is considerable ischemia that will improve from revascularization. In case, the patients with NSTEMIs show hemodynamic instability, they may undergo urgent coronary angiography followed by revascularization. The treatment of thrombolytic agents is contraindicated in such patients.

The treatment regimens offered to the patient are based on the  ST segment elevations on an ECG that results from complete blockade of  a coronary artery. However, in case of NSTEMIs, there is narrowing of a coronary artery with diminished but still preserved flow to the distal myocardium. These patients are administered the anticoagulation and antiplatelet agents for preventing the blockade in the narrowed artery. In case of Reperfusion dysrhythmia, the presence of Accelerated idioventricular rhythm (AIVR) that looks like slow ventricular tachycardia indicates the successful reperfusion.

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