Heart Attack

Symptoms of a heart attack can differ widely from person to person and can be different between men and women. Not all heart attacks begin with the sudden and severe symptoms that come when the blood flow to the heart gets blocked. Heart attack symptoms can start slowly and be mild or they can be very severe and sudden. Symptoms also may come and go over several hours. 

If you are having a heart attack, you may experience one or more of the symptoms below:

• Chest pain, heaviness or discomfort in the center or left side of the chest (this is the most common symptom)
• Pain or discomfort in one or both arms, your back, shoulders, neck, jaw or above your belly button
• Shortness of breath when resting or doing a little bit of physical activity
• Sweating a lot for no reason
• Nausea (feeling sick to the stomach) and vomiting
• Light-headedness or sudden dizziness
• Rapid or irregular heartbeat, feeling unusually tired for no reason, sometimes for days (this is more common in women) 

If you have previously had a heart attack, your symptoms may not be the same for another one. 

Silent heart attacks

Heart attacks can happen without any symptoms or with very mild symptoms. These are called silent heart attacks. Silent heart attacks are more common in older adults and in people who have high blood sugar or diabetes.

Any time you think you might be having a heart attack, do not ignore it. Call 9-1-1 for emergency medical care, even if you are not sure that you are having a heart attack.

• Acting fast can limit damage to your heart and save your life. The 9-1-1 operator or emergency medical services (EMS) personnel can give you advice that can help prevent damage to your heart.
• An ambulance is the best and safest way to get to the hospital. Do not drive to the hospital or let someone else drive you. EMS personnel can check how you are doing and start tests and lifesaving medicines right away. People who arrive by ambulance often get faster treatment at the hospital.
• Every minute matters. Never delay calling 9-1-1, taking aspirin or doing anything else you think might help. 

Knowing the difference between stable angina (chest pain in people who have coronary artery disease) and a heart attack is important.

• The pain from stable angina usually happens after physical activity and goes away in a few minutes when you rest or take medicine to treat it. Patients with stable angina can still lead active lives usually with medications and do not need to be hospitalized unless there is a distinct change in the pattern and severity of their symptoms. When this occurs, symptoms are called “unstable angina” and may be the earliest signs of an impending heart attack.
• The pain from a heart attack takes on a different pattern from stable angina. Chest pains can recur more frequently, be more intense and associated with other symptoms such as shortness of breath, sweating, nausea and vomiting. Heart attack pain may not go away when you rest or take medicine.

If you suspect your angina is becoming unstable or you may be having a heart attack, call 9-1-1. 

The most common cause of a heart attack is coronary artery disease, which is the most common type of heart disease. This is when your coronary arteries cannot carry enough oxygen-rich blood to your heart muscle due to the buildup of plaque inside your arteries. The buildup of this plaque is called atherosclerosis. This can happen over many years and it can block blood flow to parts of your heart muscle. Plaques that narrow arteries slowly over time can cause angina.

Unpredictably, an area of plaque can break open inside your artery. This causes a blood clot to form on the plaque’s surface. If the clot becomes large enough, it can block blood flow to your heart. This is the most common form of an acute heart attack. If the blockage is not treated quickly, a part of your heart muscle can die.

Other Causes of a Heart Attack 

Not all heart attacks are caused by blockages from atherosclerosis. When other heart and blood vessel conditions cause a heart attack, it is called myocardial infarction in the absence of obstructive coronary artery disease (MINOCA). MINOCA is more common in women, younger people and racial and ethnic minorities, including Black, Hispanic/Latino and Asian people. 

Conditions that can cause MINOCA have different effects on the heart:

• Small plaques in your arteries may not block your blood vessels or may not be detected on testing. However, these mild plaques can still break open or their outer layer can wear away. This can cause blood clots to form on these plaques which can then suddenly block blood flow through your coronary arteries. The formation of small plaques is more common in women, people who smoke and people who have other blood vessel conditions.
• A sudden and serious spasm (tightening) of your coronary artery can block blood flow to your heart, even if there isn’t a large buildup of plaque. Smoking is a risk factor for a coronary spasm. If you smoke, you may be more likely to have a spasm triggered by extreme cold or very stressful situations. Drugs like cocaine may also cause coronary spasms.
• Viruses and toxins can damage the heart muscle directly and cause severe symptoms and other findings like those of a heart attack due to blocked arteries.
• Tako-tsubo or “Broken Heart Syndrome” is a rare condition that develops when extreme stress causes a portion of the heart muscle to stop working properly. This is thought to occur because of a massive surge in adrenaline associated with severe emotional or psychological stress in people who experience major life trauma. An example could be the recent death of a loved one, hence the name “broken heart syndrome.” Such extreme levels of adrenaline can not only raise blood pressure to dangerous levels, it can also directly tighten the small arteries, reduce blood flow and cause damage to the muscle in the affected area. This condition affects more women than men and is more common after menopause. Although this is a very serious and potentially life-threatening problem, patients generally do very well and heart function frequently returns to normal within days after appropriate management and treatment.
• Spontaneous coronary artery dissection (SCAD) occurs when a tear forms inside your coronary artery. A blood clot can then form at the tear, or the torn tissue itself can block your artery. SCAD can be caused by stress, extreme physical activity and pregnancy. This condition is more common in women who are under 50 years old or pregnant and in people who have Marfan syndrome.
• Coronary artery embolism occurs when a blood clot travels through your bloodstream and gets stuck in your coronary artery. This can block blood flow through your artery. This is more common in people who have atrial fibrillation, artificial valves, or conditions that raise the risk of blood clots, such as thrombocytopenia or pregnancy.

Other conditions may cause symptoms like a heart attack. Your doctors may or and review other test results to look for other causes of symptoms if an acute heart attack is ruled out. 

Certain risk factors make it more likely that you will develop coronary artery disease and have a heart attack.

Risk factors you can control 

Lifestyle habits, such as:

• An unhealthy diet, including eating too many foods high in saturated fat or sodium
• Overweight and obesity
• Lack of regular physical activity
• Smoking
• Other medical conditions, such as:
  • High blood cholesterol
  • High blood pressure or preeclampsia (high blood pressure during pregnancy)
  • High blood sugar or diabetes
  • High blood triglycerides 

If you have three or more of these conditions that raise your risk for heart disease, it is called metabolic syndrome. This greatly increases your risk of a heart attack.

Risk factors you can’t control

• Age: The risk of heart disease increases for men after age 45 and for women after age 55 (or after menopause).
• Family history of early heart disease: You have a higher risk if your father or a brother was diagnosed with coronary artery disease before 55 years of age or if your mother or a sister was diagnosed with coronary artery disease before 65 years of age.
• Infections from bacteria and viruses 

Calling 9-1-1 for an ambulance and getting to the emergency room quickly if you suspect a heart attack is critical. 

• An electrocardiogram (EKG) is the most common initial test and in most situations, will be performed by the ambulance team if a heart attack is suspected. Once at the hospital, you will get an EKG within minutes of your arrival at the hospital to further assess whether you may be having a heart attack. Based on the results of the EKG, your doctor will ask you about your medical history, do a physical exam and then order more tests.
• Blood tests: During a heart attack, heart muscle cells die and release specific proteins into your bloodstream. Blood tests can measure the amount of these proteins. For example, troponin leaks into the blood when heart muscle cells die during a heart attack and this protein can be accurately detected in almost all cases of heart damage. Blood tests often are repeated over hours to even days to check for changes over time.
• Heart imaging tests: Imaging tests, such as a chest X-ray, echocardiograms (ultrasound of the heart) or computed tomography (CT) help your doctor check whether your heart is working properly. You may also need a stress test, which can help your doctor assess the amount of damage to your heart, determine how much you can tolerate after the event and assess your overall risk going forward.

In addition, since disorders other than CAD can damage heart muscle, stress testing and CT imaging can better assess if the heart attack was truly due to blocked coronary arteries. Information gathered from such testing can be crucial in helping your doctor decide on the best treatment options for you, both in the emergency setting and for long term management.

Preventing heart attacks involves managing risk factors through heart-healthy lifestyle changes, including a balanced diet, regular exercise, quitting smoking and controlling stress. Medications may also be prescribed to manage cholesterol, blood pressure and diabetes, or to prevent clot formation. Cardiac rehabilitation programs can support recovery by providing exercise training, education on heart health and counseling. Continuous monitoring and adherence to prescribed treatments are essential to prevent another heart attack and maintain a healthy heart.