World Heart Day: Can heart attack be detected by a blood test?

A heart attack is caused when plaque builds up in the arteries and leads to blockage. Here’s how it can be detected.

Heart attack is a medical emergency that needs to be addressed immediately as it can quickly turn fatal. A heart attack is caused when plaque builds up in the arteries and leads to blockage. When this plaque ruptures, blood clot is formed which causes heart attack. Due to this, the blood and oxygen doesn’t reach heart and irreversible damage starts to happen to heart muscles and become fatal. People with family history of heart ailments are more susceptible to such cardiac events. Those leading unhealthy lifestyle and having chronic issues like hypertension, high cholesterol levels and diabetes may also be at higher risk of heart attack.

Heart attack symptoms include chest pain, tightness, discomfort, fatigue, cold sweat, heartburn, nausea, shortness of breath. Sometimes heart attacks are silent, and symptoms can feel like sore muscle in heart, ache in jaw or arm or upper back, fatigue or indigestion.

Any such discomfort or symptom should not be ignored, and one must approach a hospital’s emergency immediately.

There are a couple of ways one can know if they are having a heart attack:

ECG

An Electrocardiogram (EKG) will be performed immediately after you arrive at the hospital. It records the electrical signal from the heart and can detect a heart attack. Not all heart attacks show up on the first ECG. An ECG can also show evidence of a previous heart attack.

2. X-Ray

Imaging tests like a chest X-ray or computed tomography (CT) can also help determine the possibility of a heart attack. One can also be recommended a stress test which can help your doctor determine the amount of damage to your heart.

3. Blood test

“Whenever a heart attack occurs, muscle proteins from the heart get released from the damaged muscle to the blood. Heart muscle proteins like myoglobin, troponin I, troponin R, are released. Various diagnostic tests like troponin assay tests are available to detect and quantify the degree of myocardial infarction. The greater the value, the larger is the myocardial infarction.

These diagnostic tests are useful not only in diagnosing early attacks, but also prognosticates the patient’s prognosis,” says Dr Kala Jeethender Jain, Consultant Interventional Cardiologist.

“These proteins typically rise within 6 to 12 hrs after attack, reaches a plateau and then normalizes after 48 hrs. Proteins like troponins are detected up to 10 days after attack. If the patient has typical cardiac symptoms and troponin test initially is negative, then a repeat test again has to be done demanding the clinical situation because many times a repeat sample turns out to be positive. Nowadays high sensitive troponins (HS trop) are available in emergency rooms which can even detect minor attacks too,” adds Dr Jain.