MYOCARDIAL INFARCTION (MI) How can we diagnose it right away?

This topic I will share my experiments from my ICU of Cardiac Emergency Dept about myocardial infarction (MI), how to diagnose it as soon as possible and the management of it.
1. INTRODUCTION: 
       Myocardial infarction (MI) is defined as a clinical (or pathologic) event caused by myocardial ischemia in which there is evidence of myocardial injury or necrosis.
And this term belong to the term ACS: Acute coronary syndrome.
      The term acute coronary syndrome (ACS) is applied to patients in whom there is a suspicion of myocardial ischemia. There are three types of ACS:

1. ST elevation (formerly Q-wave) MI (STEMI)
2. Non-ST elevation (formerly non-Q wave) MI (NSTEMI)
3. Unstable angina (UA)

         The first two are characterized by a typical rise and/or fall in biomarkers of myocyte injury.
The thing is when the patient with a terrible angina pectoris come to your department, your initial care should include the early and simultaneous achievement of four goals:

• Confirmation of the diagnosis by electrocardiogram (ECG) and biomarker measurement
• Relief of ischemic pain
• Assessment of the hemodynamic state and correction of abnormalities that may be present
• Initiation of antithrombotic and reperfusion therapy if indicated

Criteria are met when there is a rise and/or fall of cardiac biomarkers, along with supportive evidence in the form of typical symptoms. But usually, you can't wait until you have the result of cardiac biomarkers :) In that situation, you should remember that:
 A full 12-lead ECG should be obtained and interpreted within 10 minutes after the patient enters your medical facility. The ECG can provide the following useful information in patients with acute coronary syndrome

• The ECG is the only modality capable of making a diagnosis of ST elevation MI. It is the most important tool in defining the onset of the coronary event and the urgency for immediate revascularization

1. You see ST segments elevate really high, Oh my God, no need to hesitate, start your treatment right away. But if:
2. ST segments don't elevate or the previos ECG of the patient elevate already, at that moment you should compare to the previous ECG and find suggestive electrocardiographic changes, if the ECG has changed or it just appear a LBBB, you can start your treatment. :)
3. If you can, carry out an echocardiogram, an imaging evidence of new loss of viable myocardium or new regional wall motion abnormality will help you diagnosis.
4. You can make a test by give them nitroglycerine, if it can relieve their angina we can think more about ACS, but if don't, we can say nothing because it maybe an MI. (MI is not respont to nitroglycerine, we can use Morphin to relieve their pain)

2. MANAGEMENT:

Once the diagnosis of an acute STEMI is made, the early management of the patient involves the simultaneous achievement of several goals:

• Relief of ischemic pain
• Assessment of the hemodynamic state and correction of abnormalities that are present
• Initiation of reperfusion therapy with primary percutaneous coronary intervention (PCI) or fibrinolysis
• Antithrombotic therapy to prevent rethrombosis or acute stent thrombosis
• Beta blocker therapy to prevent recurrent ischemia and life-threatening ventricular arrhythmias

This is then followed by the in-hospital initiation of different drugs that may improve the long-term prognosis:

• Antiplatelet therapy to reduce the risk of recurrent coronary artery thrombosis or, with PCI, coronary artery stent thrombosis
• Angiotensin converting enzyme (ACE) inhibitor therapy to prevent remodeling of the left ventricle
• Statin therapy
• Anticoagulation in the presence of left ventricular thrombus or chronic atrial fibrillation to prevent embolization

And here are some guidelines I ussualy use: Download it to support me share more :)

Guideline ESC 2012 - Acute MI

Guideline of ACC/AHA about STEMI 2013

Guideline for PCI

ECG in Acute MI

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