Blood test

• Complete blood count
• Cardiac enzymes
• Serum electrolytes
• Renal function test- blood urea and serum creatinine
• Lipid profile
• C-reactive protein

Cardiac enzymes

In patients with suspected heart attacks, obtain cardiac enzymes at regular intervals, starting upon admission and serially for as long as 24 hours.

Troponin T and I levels

• Troponins have greater specificity and sensitivity than creatine kinase levels
• They are useful both diagnostically and prognostically.
• Serum levels increase within 3-12 hours from the onset of chest pain, peak at 24-48 hours, and return to baseline over 5-14 days.

Creatine kinase levels

Creatine kinase comprises 3 isoenzymes, (CK-MM), which is found mainly in skeletal muscle; (CK-BB), predominantly found in the brain; and myocardial muscle creatine kinase (CK-MB), which is found mainly in the heart.

CK-MB levels increase within 3-12 hours of onset of chest pain, reach peak values within 24 hours, and return to baseline after 48-72 hours. Levels peak earlier (wash out) if reperfusion occurs.

Myoglobin levels

Myoglobin levels are highly sensitive but not specific, urine myoglobin levels rise within 1-4 hours from the onset of chest pain and fall within 24 hrs.

Serum electrolytes

Need to close monitoring serum potassium and magnesium levels

Renal function test

Creatinine level is also needed prior to initiating treatment with an angiotensin-converting enzyme (ACE) inhibitor.

Complete blood count (CBC)

• CBC counts if myocardial infarction is suspected to rule out anemia as a cause of decreased oxygen supply and prior to giving thrombolytics.
• Leukocytosis is common in the setting of acute myocardial infarction.
• A platelet count is necessary if platelet aggregation inhibitors are used.

Lipid level profile

• This is useful if obtained at the time of admission because levels can change after 12-24 hours of an acute illness.
• Increase in total cholesterol levels, LDL- cholesterol and triglycerides are at higher risk for thrombus formation
• Increase in HDL – cholesterol levels age good to heart and are cardioprotective

C- reactive protein

C- reactive protein levels are elevated in acute coronary syndrome.