Heart Attack: Symptoms, Causes and What Happens in Hospital

A heart attack is a medical emergency. Knowing the warning signs and acting quickly can limit damage to the heart. This article explains what a heart attack is, what causes it and how it is treated, using information from the NHS, MedlinePlus and the US CDC.

What is a heart attack?

A heart attack, also called a myocardial infarction, happens when blood flow to the heart is blocked. Without oxygen-rich blood, heart muscle starts to be damaged. MedlinePlus explains that quick treatment can prevent or limit that damage.

A heart attack is not the same as cardiac arrest. During a heart attack the heart usually keeps beating, although a heart attack can sometimes lead to cardiac arrest.

Common symptoms

Symptoms vary from person to person and can be mild or severe. Sources describe these warning signs:

• Chest pain or discomfort that may feel like pressure, squeezing, fullness or crushing. It can be in the centre or left of the chest and may last several minutes or come and go.
• Pain that spreads to the arms, shoulders, neck, jaw or back.
• Shortness of breath, which can happen with chest discomfort or even before it.
• Feeling or being sick, sweating or a cold sweat.
• Feeling light-headed, dizzy or faint.
• A feeling like indigestion or heartburn, or feeling full or bloated.
• Pale, blue or grey skin. The NHS notes that on black or brown skin this may be easier to see on the palms of the hands.

The CDC adds that women are more likely to have unusual or unexplained tiredness and nausea or vomiting.

What causes a heart attack?

The most common cause is coronary artery disease. Over years, a fatty material called plaque builds up inside the heart's arteries. MedlinePlus explains that a plaque can break open and a blood clot can form on it and block the artery. Less often, a severe spasm of a coronary artery cuts off the blood supply.

The NHS lists these things that raise the risk:

• Smoking
• High blood pressure
• High cholesterol
• Diabetes
• Being overweight or obese
• A close relative who has had a heart attack

How is a heart attack diagnosed?

In hospital, doctors look at symptoms, run blood tests (such as a test for a substance called troponin) and use heart tests. The NHS says an electrocardiogram (ECG) and blood tests come first. If they point to a heart attack, further tests may include an echocardiogram, which checks for heart damage, and a coronary angiogram, which finds the exact blockage and can sometimes be followed by treatment in the same procedure.

Treatment and lowering your risk

In hospital

Treatment depends on how serious the heart attack is, and your hospital team decides what is right. The NHS describes these options:

• Medicines to treat the blockage and improve blood flow.
• Coronary angioplasty, which opens a blocked artery, usually using a small mesh tube called a stent.
• Coronary artery bypass surgery, which uses blood vessels from elsewhere in the body to go around a blockage.

After a heart attack, people are usually given long-term medicines to lower the chance of another one. The NHS names classes such as antiplatelets, statins, ACE inhibitors and beta-blockers. Your doctor decides which, if any, are suitable for you.

Lowering your risk

The NHS says heart attacks cannot always be prevented, but you can lower your risk by:

• Stopping smoking
• Keeping blood pressure and cholesterol at healthy levels
• Eating a balanced diet with less salt and saturated fat
• Keeping to a healthy weight
• Exercising regularly
• Cutting down on alcohol

When to see a doctor

Do not wait to see if symptoms pass. Call emergency services straight away if you or someone else has chest pain that is tight or squeezing, pain spreading to the arms, neck or jaw, severe difficulty breathing, pale, blue or grey skin, or has collapsed and is not responding normally. The NHS advises not to drive yourself to hospital. MedlinePlus says to call even if you are not sure it is a heart attack, because emergency crews can begin treatment on arrival.

In an emergency, call your local emergency number (112 in India, 911 in the United States).