A blood test involves taking a small sample of blood for testing in the laboratory. A doctor can use it to diagnose heart diseases and assess heart health. The different types of blood tests employed for this purpose are:

• Cardiac enzyme tests and troponin tests – To diagnose a heart attack.
• C-reactive protein test – To detect high levels of inflammation and risk of heart disease.
• Full blood count – To detect infections and monitor heart conditions.
• Thyroid function tests – To determine whether the irregular heart rate occurs due to hormonal imbalances.
• Lipid profile – To measure cholesterol level.
• Lipoprotein, homocysteine, and fibrinogen tests – To assess the risk of developing coronary artery disease.
• Liver tests – To evaluate the functioning of the liver.
• Clotting screen – To measure the rate of blood clotting.
• BNP (B-type natriuretic peptides) test – To check for signs of heart failure.
• Urea and Electrolyte test – To assess the overall functioning of the heart.  

Read more about various cardiac disorders that require blood testing to assess risk.

How are blood tests performed? :

Blood is generally taken by inserting a needle in the vein inside the elbow. A pathologist can also take it from the vein on the back of the hand. The veins in these regions are used as they are closer to the surface of the skin. Before inserting the needle, a tourniquet (tight band) is wrapped tightly around the arm. It is tied just above the region where the blood is being withdrawn. This action pushes the veins to the skin’s surface, making it easier to take the blood sample. An antiseptic swab is generally used to clean this region before taking blood. The collected blood is then transferred to a vial and sent to the laboratory for analysis. After collecting the blood sample, the patient is asked to apply pressure to the area for a few minutes.

Apart form blood tests, various diagnostic tests are also performed to find out risks associated with heart problems.

Are there any risks involved in it? : ¹

Discomfort and bruising at the site where the needle was inserted are the common risks of blood tests. These are minor and usually go away after some time.

FAQs:

What preparation is required from the patient? 

The patient may consult with the doctor to know if he/she is required to refrain from eating or drinking anything before the test. It is advised to wear a loose-fitting shirt or a short-sleeved top to make it easy to reach the arm during the test.

How long does it take?

The entire test is completed within a few minutes.

Who performs it?

The phlebotomist (pathologist) usually performs blood tests. Sometimes, the nurse or the doctor may also conduct this test.

How much does it cost?

The average cost of the blood test for diagnosis of heart disease ranges from Rs. 350 to Rs. 2000.

When can I go home after the procedure?

The patient is allowed to go home immediately after the blood tests and does not require any hospitalization.