What is a heart attack?

A heart attack occurs when the blood flow to the heart muscle is blocked and the heart can’t get oxygen. Heart muscle can begin to die if the blood flow is not restored in a timely manner.

Common related conditions
Angina (Chest Pain)

Causes of heart attacks

Coronary artery disease (also known as coronary heart disease or CHD) is the primary cause of a heart attack. Coronary heart disease occurs when plaque builds up in the coronary arteries in a condition called atherosclerosis. The plaque can build up over several years.

An area of plaque can break open inside the artery to form a blood clot on the surface of the plaque. The clot can block the blood flow through an artery if it becomes large enough.

A coronary artery spasm can also cause a heart attack. Cocaine, other illegal drugs or tobacco can cause a spasm that blocks the flow of blood to the heart.

Risk factors for heart attacks

Heart attack risk factors that you are not able to control include:

  • Age — men over 45 and women over 55 are at higher risk to suffer from a heart attack.
  • Family history — if your father or brother was diagnosed with heart disease prior to age 55 or mother or sister was diagnosed prior to age 65, you are at higher risk of developing the condition and suffering a heart attack as a result.

If you have any of the risk factors below, you can reduce your risk of a heart attack by taking action to become healthier.

Symptoms of heart attacks

Symptoms of a heart attack are different for every person. Some people have only one or very few symptoms, while others have intense chest pain along with many other symptoms.

The most common signs or symptoms of a heart attack include:

  • Chest pain or discomfort — heart attacks generally involve pain, discomfort, pressure, squeezing or fullness on the left side or center of the chest.
  • Shortness of breath — shortness of breath could be your only symptom or could occur before or at the same time as chest pain. You could feel winded from resting or performing day-to-day activities.
  • Pain or discomfort in various upper body parts — some patients experience pain in their arms, back, shoulders, neck, jaw or the stomach above the belly button.
  • Cold sweats — breaking out in a cold sweat for no reason is a sign of a heart attack (especially in women).
  • Fatigue — unusual fatigue for no reason; if you are a woman, the tiredness can last for days.
  • Nausea — vomiting or feeling sick to the stomach.
  • Dizziness — light-headedness or sudden dizziness.

Heart attacks in men present differently than in women. Women are more likely to experience shortness of breath, back pain, jaw pain or nausea/vomiting. Many women think they have the flu when they are having a heart attack.

It is important to act at the first signs or symptoms of a heart attack. Early intervention can save your life or limit damage to your heart.

Diagnosis of heart attacks

A heart attack can be diagnosed based on symptoms and results of diagnostic tests.

Tests that can help diagnose a heart attack include:

  • Electrocardiogram (ECG) — will show the extent of the damage to the heart muscle as well as where it occurred; it can also measure your heart rate and rhythm.
  • Blood tests — can show heart muscle damage by measuring the levels of cardiac enzymesour doctor can determine the size of your heart attack and when it started by measuring cardiac enzymes.

Your physician may also measure your troponin levels to determine if you had a heart attack. Troponins (proteins that live inside heart cells) are released when the blood supply is blocked into the heart.

Treatments for heart attacks

Treatment for a heart attack needs to begin immediately in order to preserve as much heart muscle as possible.

Treatments for a heart attack include:


The goal of medication for heart attack patients is to prevent blood clots, stabilize the plaque and prevent platelets from sticking to the plaque. Medications should be started as soon as possible to limit heart muscle damage.

Medications used to treat a heart attack include:

  • Aspirin — prevents blood clotting
  • Antiplatelet medications — prevent blood clotting
  • Thrombolytic therapy — dissolves blood clots in the arteries

Cardiac catheterization

Cardiac catheterizations, also called cardiac cath or heart cath, can visualize a blocked artery and help the doctor determine what treatment is necessary.

A thin, hollow tube is inserted into a blood vessel that goes to the heart and a contrast dye is injected through a catheter so the doctor can see through x-rays where the arteries are blocked. Angioplasty can help relieve the symptoms of a heart attack, such as chest pain, nausea or shortness of breath by opening the blocked artery quickly and reducing damage to the heart.

Coronary angioplasty

A coronary angioplasty is also known as a percutaneous coronary intervention. If your arteries are blocked, your physician may put a coronary stent into the artery to open it up. During this procedure, your doctor will insert a thin tube (stent) into an artery that leads to the heart via a tiny incision in the leg or arm. Once the stent is in the correct location, your doctor will inflate a small balloon in the blocked artery.

Bifurcated coronary stent

A coronary bifurcation lesion occurs near a division in a major coronary artery where a main artery branches into two smaller arteries. Though approximately 20% of percutaneous coronary interventions involve coronary bifurcation lesions, cardiologists find stenting them extremely challenging. Recently, technology has improved and products have been developed to treat bifurcated lesions. The FDA recently approved new bifurcated coronary stents and more are in development to more effectively treat patients who have bifurcated coronary lesions.

Bioresorbable coronary stent

A bioresorbable stent is a coronary stent that can dissolve or be absorbed in the body. Bioresorbable stents are also known as biodegradable or naturally-dissolving stents. The goal of this stent is to support vessel healing during the three months following surgery, and then when it is no longer needed, the body will resorb it.


An atherectomy is a minimally invasive endovascular cardiology procedure used to remove plaque buildup from the artery walls. During the procedure, your cardiologist will insert a thin tube (catheter) into a small incision in the leg and use special tools to remove the plaque. An atherectomy is an alternative to an angioplasty and is typically used to correct peripheral arterial disease.

Coronary bypass surgery

Coronary bypass surgery, also known as coronary artery bypass graft (CABG), is a cardiovascular surgery that is performed to restore blood flow to a blocked coronary artery. During the procedure, your cardiovascular surgeon will replace a damaged portion of a heart artery with a healthy blood vessel from your leg, arm or chest.

Heart attack symptoms such as chest pain, back pain and shortness of breath typically improve after coronary bypass surgery.

A CABG is typically indicated if your coronary artery is more than 50 percent blocked and the blockage is caused by arteriosclerosis or atherosclerosis.

Minimally-invasive coronary bypass surgery

Minimally-invasive coronary bypass surgery is a less invasive form of coronary bypass surgery used to open blocked arteries. In a traditional coronary bypass surgery, your heart is stopped and you are put on a heart-lung machine. The heart-lung bypass will keep your body functioning while the surgeon fixes the blocked arteries. In a minimally invasive coronary bypass procedure, the surgeon can perform the surgery while the heart is still beating.

The two types of beating-heart surgery are minimally invasive direct coronary artery bypass and off-pump coronary artery bypass.

  • Minimally invasive direct coronary artery bypass procedure — the surgeon will cut small incisions above the diseased vessels and fix the arteries through these small cuts. 
  • Off-pump coronary artery bypass — your cardiovascular surgeon will make a large incision, but you will not have to be placed on a heart-lung bypass machine.


The main goal of a cardiomyoplasty is to boost the ability of the heart to pump effectively by taking skeletal muscles (from back or abdomen) and wrap them around the failing heart. To make the muscle contract, a pacemaker must be implanted.

Cardiac rehabilitation

The goal of a cardiac rehabilitation program is to improve your cardiovascular health after a heart attack. During cardiac rehabilitation, you will work with your Mercy Health team to learn appropriate exercises for your fitness level and heart healthy living, such as good nutrition and stress management techniques.

The Mercy Health cardiac rehabilitation team includes doctors, nurses, nutritionists, pharmacists and other healthcare professionals who work together to help you get back to your day-to-day activities as soon as possible.

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