What Causes a Heart Attack: 9 Causes & Risk Factors

Causes of a heart attack include conditions that reduce blood flow to the heart, such as atherosclerosis and high blood pressure. These problems can narrow or damage arteries, making it harder for oxygen-rich blood to reach the heart.

A heart attack can also be caused by diabetes, obesity, smoking, arrhythmias, blood clots, and the use of certain medications or drugs. These factors can increase strain on the heart or interfere with circulation, raising the risk of serious heart problems.

Common symptoms of a heart attack include chest pain or pressure, shortness of breath, and pain that may spread to the arms or jaw. Treatment and prevention involve managing underlying health conditions, maintaining healthy lifestyle habits, and seeking immediate medical attention if these signs appear.

Heart attack causes

The main causes and risk factors for a heart attack include:

1. Atherosclerosis

Atherosclerosis is one of the main causes of heart attack. It often develops after years of eating fatty, high-cholesterol foods, which lead to fatty plaque buildup in the arteries.

These plaques can also form in the heart’s main blood vessels, reducing blood flow and causing symptoms such as chest pain, shortness of breath, and heart attack.

What to do: If you think you may have atherosclerosis, you should see your primary care provider or a cardiologist for an evaluation.

Treatment may include prescription medicines such as statins to lower cholesterol, blood pressure medications, or surgery to restore blood flow. The doctor may also advise you to adhere to a low cholesterol diet. 

2. High blood pressure

When blood pressure is very high, the heart has to work harder to pump blood through the blood vessels. Hypertension can also damage the artery walls and increase the risk of blood clot formation. These changes can reduce blood flow to the heart and increase the risk of a heart attack.

What to do: If hypertension is suspected, it is important to consult a primary care provider or cardiologist. Treatment may involve medications such as antihypertensives or diuretics.

Very high blood pressure can cause symptoms like headache, drowsiness, or chest pain, which should be assessed urgently in a hospital setting.

3. Diabetes

Uncontrolled diabetes can damage blood vessel walls when blood sugar levels remain high. This can speed up the development of atherosclerosis, which narrows the arteries and increases the risk of a heart attack.

What to do: If diabetes is suspected, it is important to consult a primary care provider or an endocrinologist for evaluation.

Proper treatment can help control blood sugar levels and prevent complications, such as diabetic neuropathy. Learn more about diabetes medications a doctor may prescribe to help manage blood sugar levels. 

4. Obesity 

Obesity increases the risk of cardiovascular disease because it is often linked to physical inactivity and a diet high in sugar and fat. These factors can lead to conditions like diabetes, high cholesterol, and high blood pressure, which raise the risk of a heart attack.

What to do: Adopting healthy habits to support weight loss is recommended, along with consulting an endocrinologist and a registered dietitian for proper guidance. Use our calculator to help determine your ideal weight.

5. Smoking

Frequent tobacco use can inflame and harden the blood vessels. This makes the heart work harder and increases the risk of heart attack, stroke, blood clots, and aneurysms.

According to the CDC, cigarette smoking greatly increases the risk of heart disease, and quitting smoking is one of the main healthy habits that can help lower the risk of heart disease and heart attack.

What to do: Quitting smoking is one of the best ways to reduce the risk of a heart attack and other cardiovascular diseases. Medical care, counseling, and psychological support can help make quitting easier.

6. Drug and alcohol use

Using illicit drugs, such as cocaine or marijuana, and drinking too much alcohol can increase the risk of a heart attack by raising blood pressure. Cocaine can also narrow the arteries that supply blood to the heart, reducing blood flow and increasing the risk of a heart attack.

What to do: Avoid illicit drug use and limit alcohol intake to help reduce the risk of a heart attack, cirrhosis, hypertension, and other health problems. Counseling or support programs may be helpful for people who have difficulty stopping substance use.

7. Arrhythmias

Arrhythmias that cause a fast heart rate can overload the heart and affect blood flow. This can lead to symptoms such as chest pain and shortness of breath, and may increase the risk of a heart attack.

What to do: If an arrhythmia is suspected, a primary care provider or cardiologist should be consulted for assessment and treatment. Symptoms such as chest pain or shortness of breath should be assessed urgently in the hospital.

8. Medication side effects

Medications like triptans (used for migraines), some antibiotics, and chemotherapy drugs can rarely affect heart function. Triptans may cause narrowing of coronary arteries, while other drugs can affect heart rhythm or damage heart cells (cardiotoxicity), increasing the risk of a heart attack.

What to do: Before starting any medication, it is important to share your full medical history with your healthcare provider and follow the prescribed treatment exactly as directed to reduce the risk of serious side effects.

9. Embolism

An embolism usually occurs when a blood clot forms in the heart or blood vessels and travels through the bloodstream. It is more common in conditions like cardiomyopathy, valve disease, or arrhythmias such as atrial fibrillation.

These clots can block the arteries that supply blood to the heart, which can lead to a heart attack.

What to do: Conditions that increase the risk of clots, such as atrial fibrillation or valve disease, should be closely monitored and treated by a cardiologist. Treatment often includes anticoagulant medications to help prevent clot formation.

How to reduce your risk of a heart attack

According to the American Heart Association, heart attack risk can be reduced by managing key risk factors such as tobacco use, physical activity, blood pressure, cholesterol, and blood glucose levels.

To decrease the risk of a heart attack, the following habits are recommended:

• Maintain a healthy diet
• Exercise regularly
• Quit smoking
• Aim for a healthy weight through balanced habits
• Avoid excessive alcohol consumption
• Avoid illicit drugs, such as cocaine or marijuana
• Take medications only as prescribed by a healthcare provider

It is also important to follow the recommended treatment plan for hypertension, high cholesterol, and diabetes.