What Happens During a Heart Attack

Heart problems often come as a surprise, which makes it easy to dismiss symptoms like chest pain or shortness of breath. But understanding what happens during a heart attack can save your life.

A heart attack is a serious and potentially life-threatening form of cardiovascular disease that occurs when blood flow to the heart muscle is blocked. Joseph Cookman, DO, FACC, UnityPoint Health, explains the stages of a heart attack, warning signs to watch for and the importance of going to the hospital right away. 

What is a Heart Attack?

In simplest terms, a heart attack is when part of the heart muscle doesn’t get enough blood. The most common cause is a partial or complete blockage of a blood vessel, preventing enough oxygen or blood from reaching the heart.

Dr. Cookman explains the four stages of a heart attack:

• Stable angina: There’s a narrowing of the blood vessel. This stage is often diagnosed using a stress test. Symptoms occur during periods of high activity, such as climbing multiple sets of stairs, which is when the heart doesn’t receive enough blood to sustain the activity.
• Unstable angina: Plaque and blockage build up, making symptoms occur more frequently with less physical activity. Enough blood gets to the heart during periods when there is no chest pain. There’s no heart damage yet. A repeat stress test isn’t always performed in this case, because there’s a high likelihood of finding coronary artery disease. Instead, a cardiac catheterization may be the preferred first test.
• Heart attack with partial blockage: While the blockage isn’t complete, there's enough to cause heart damage.
• Full heart attack or complete blockage: In many cases, a heart attack occurs when a coronary artery is completely blocked, stopping blood flow to part of the heart muscle and causing ongoing damage. Classic heart attack signs are present and persistent, such as chest pressure or pain, shortness of breath, nausea or pain radiating to the arm or jaw. Immediate medical attention is essential to restore blood flow and prevent further heart damage or death.

"People ignore symptoms, which are usually taking place for weeks or months before finally having a heart attack with a complete blockage. At that point, the heart isn’t getting blood, and it can go into a life-threatening rhythm, which presents as cardiac arrest," Dr. Cookman says.

In these moments, a patient may experience a rapid, abnormal heartbeat or dangerously slow heart rate (bradycardia) as the heart's electrical system begins to fail. This occurs because the lack of oxygenated blood damages the cells responsible for signaling the heart to pump, potentially leading to a total stop of heart activity.

What Causes a Heart Attack?

Dr. Cookman says many factors can lead to a heart attack. Some, like family history, we can’t control. But others, such as smoking, high blood pressure (hypertension), high cholesterol, diabetes and stress, we can through proper management.

These same risk factors also increase your risk of developing peripheral artery disease, which affects blood flow to your limbs. Uncontrolled high blood pressure can damage artery walls over time and accelerate plaque buildup.

What are the Signs of a Heart Attack in Women and Men? 

Both men and women are at risk for heart disease, including a heart attack. While men usually develop it younger, women are just as at risk but present later in life. Dr. Cookman lists how heart attack symptoms in both men and women progress:

• Onset: Heart attack symptoms (shortness of breath, sharp chest pain, arm pain, etc.) usually start gradually, with the intensity of those symptoms coming and going.
• Provocation: Pain from symptoms is “provoked,” or gets worse, with physical activity or exercise. Symptoms improve with rest.
• Quality: How heart attack symptoms are felt in other parts of the body, like the stomach, shoulders, arms and jaw.
• Radiation: How heart attack symptoms are felt in other parts of the body, like the stomach, shoulders, arms and jaw.
• Site: Symptoms don’t always occur in one spot. For example, someone might experience a generalized ache across the whole chest, rather than just over the heart.
• Time: How long heart attack symptoms occur. Mild heart attack symptoms might only occur for two to five minutes then stop with rest. A full heart attack with complete blockage lasts much longer, sometimes more than 20 minutes.

What is a Widow-maker?

A widow-maker refers to a severe blockage of the left anterior descending (LAD) artery. Because this artery supplies a large portion of the heart muscle, a blockage can cause extensive damage. Immediate treatment is lifesaving.

What to Do If You or Someone Else is Having a Heart Attack

“If you experience anything that seems like heart attack symptoms, call 911 immediately. You can’t ignore something as serious as a heart attack, or it might be the last time you ever brush anything off. It’s better to be seen by a medical professional than to assume it’s not a heart attack,” Dr. Cookman says.

If you’re with someone who appears to be having a heart attack, calling 911 is still the very first thing you should do.

“Getting medical support for that person as soon as you can is always your first action. When waiting for an ambulance to arrive, taking aspirin is a reasonable step. If this isn’t the first heart problem for the individual, taking nitroglycerin (used to treat chest pain) is also a good measure, along with an aspirin,” Dr. Cookman says.

Even if symptoms don’t seem too serious, don’t drive to the hospital during a heart attack. This puts you and others on the road at risk.

What Happens After a Heart Attack?

Treatment often begins with coronary angiography, a specialized imaging test used to identify the blockage. During the coronary angiography, doctors determine whether a stent is needed. In many cases, one or more stents are placed to reopen the artery and restore blood flow.

If multiple or complex blockages are found, a surgeon may perform coronary artery bypass grafting, commonly known as open heart surgery.

What Can You Do to Prevent Another Heart Attack?

"If you’ve experienced a heart attack, you’re at risk to have another. Lowering your cholesterol help reduce that risk. People with diabetes are at higher risk,” Dr. Cookman says.

Talk to your doctor about knowing your coronary artery calcium (CAC) score. It’s a way to identify calcified plaque, which helps predict future risk before symptoms ever progress to the stage of angina.

Dr. Cookman also suggests being more mindful during colder months. During winter, the cold weather constricts blood vessels, which can increase blood pressure and strain the heart. Add in strenuous activities like shoveling snow, and the risk of a cardiac event increases.

Regardless of the time of year, talking to your doctor about any health changes you experience is a good idea.

“If something’s changed in the last two weeks and you’re wondering about heart attack symptoms, it’s better to get help earlier and prevent long-term consequences of heart damage,” Dr. Cookman says.