A heart attack occurs when there is a blockage or severe reduction in blood flow to a portion of the heart. It is a life-threatening medical emergency and the longer this goes on without treatment, the more damage to the heart that can happen.
Studies have found that survival rates for people hospitalized for heart attacks are approximately 90% to 97%. This varies based on the type of heart attack, which arteries are involved, and additional factors such as age and gender.
About Heart Attacks
A heart attack is the most severe form of acute coronary syndrome (ACS). This is a term for a medical emergency involving the heart’s arteries.
Like all forms of ACS, a heart attack is usually triggered by the rupture of an atherosclerotic plaque within a coronary artery (the arteries that supply oxygen to the heart muscle). This plaque rupture causes a blood clot to form, leading to blockage of the artery. The heart muscle being supplied by the blocked artery then begins to die.
A heart attack is diagnosed when there is death of a portion of the heart muscle.
Types of Heart Attacks
Most heart attacks are caused by a blockage in a coronary artery, but, in rare cases, they can be caused by a sudden spasm or tearing of an artery.
The two main types of heart attacks are:
ST-elevation myocardial infarction (STEMI) is when there is a complete blockage in a coronary artery. It is the most severe type of heart attack. Non-ST-elevation myocardial infarction (NSTEMI) is when an artery is partially blocked and severely reduces blood flow to the heart. NSTEMI is slightly more common than STEMI.
Other types of heart attacks, which are less common than STEMI or NSTEMI, are:
Coronary artery spasm is when the artery contracts or spasms severely. This narrows the artery and decreases blood flow to part of the heart muscle. Coronary artery dissection is a rare type of heart attack in which there’s a spontaneous tearing of the coronary artery wall.
The likelihood of survival depends on which arteries are affected. A blockage in the left anterior descending (LAD) artery, a branch of the left coronary artery, has the highest risk of death.
A widowmaker heart attack is also associated with an increased risk of heart failure and stroke, but it is less common than a blockage to the right coronary artery (RCA).
One study found that the unadjusted death rate for STEMI of the LAD was 7.1%, compared to 5.4% for the other branch of the left coronary artery (left circumflex artery, LCx) and 4.8% for the right coronary artery.
There can also be significant differences in outcomes between men and women. Research has found that among people hospitalized for a first-time heart attack, women had a higher death rate than men for both STEMI (9.4% vs. 4.5%) and NSTEMI (4.7% vs. 2.9%). However, the gap wasn’t as pronounced for NSTEMI when additional factors were taken into account.
The study also found that women who had a severe heart attack (STEMI) had a 20% increased risk of dying or developing heart failure within five years compared to men.
Consequences and Dangers
To a large degree, the outcome of a heart attack depends on how much the heart muscle dies. This is largely determined by which coronary artery is blocked, where in the artery the blockage occurs, and how much time passes before the artery can be re-opened.
A blockage near the origin of an artery will affect more of the heart muscle than a blockage farther down the artery. A blockage that persists for five or six hours will cause substantially more heart muscle death than a blockage that is reversed quickly.
If the extent of heart damage is severe, acute heart failure can occur in tandem with the heart attack, a dangerous combination. Even if the extent of the damage is minimal to moderate, heart failure is more likely to occur later on due to the underlying injury sustained by the heart muscle.
A heart attack can also produce dangerous heart rhythm problems known as arrhythmias, including tachycardia (rapid heartbeat) and fibrillation (irregular rapid heartbeat). After the heart attack, scarred cardiac tissue can lead to permanent electrical instability and recurrent arrhythmia.
Cardiac arrest and sudden death are risks that are present both during an acute heart attack and to a lesser extent after the recovery.
Why the First Hours Are Critical
For anyone having a heart attack, getting rapid medical attention is absolutely critical. Both the short-term and the long-term consequences of a heart attack are largely determined by how much of the heart muscle dies. With rapid and aggressive medical treatment, the blocked artery can usually be opened quickly, thus preserving most of the heart muscle.
If treatment is delivered within three or four hours, much of the permanent muscle damage can be avoided. But if treatment is delayed beyond five or six hours, the amount of heart muscle that can be saved drops off significantly. After about 12 hours, the damage is often irreversible.
Recognizing the Signs
Getting rapid and appropriate medical care requires you to recognize the signs of a heart attack and seek medical help the moment you think you might be having one.
While chest pain, especially in the center or left side of the chest, is the classic symptom of a heart attack, other kinds of symptoms can occur in addition to (or instead of) chest discomfort.
Symptoms of a heart attack include:
Chest pain or discomfortPain or discomfort in the arms (one or both), shoulders, back, neck, jaw, or stomachFeeling weak, light-headed, or faintBreaking out in a cold sweatShortness of breathNausea or vomitingUnusual or explained tiredness
Chest pain or discomfort is the most common symptom in both men and women. It can feel like uncomfortable pressure, squeezing, fullness, or pain that lasts more than a few minutes or can go away and come back.
However, women are more likely than men to experience some of the other symptoms. The first symptoms in women may be shortness of breath, nausea or vomiting, and back or jaw pain.
Anyone who has risk factors for coronary artery disease ought to be alert to these symptoms. Even so, there are times when the symptoms may be uncertain or less overt, and people will not act immediately because the signs aren’t “as severe” as they assume.
What to Do If You Recognize a Heart Attack
If you think there’s any chance you or someone else may be having a heart attack, you need to get medical help as quickly as possible. Even if it turns out to be something else, it is better to act quickly than risk putting your life on the line.
Silent heart attacks may cause subtle symptoms such as:
Unexplained fatigue Shortness of breath Discomfort in the throat, neck, jaw, or arm Chest pain that may be mistaken as heartburn
If you recognize the signs of a heart attack, call 9-1-1 immediately. The sooner that treatment begins, the greater likelihood that you can minimize damage to the heart.
The person having the symptoms should not drive. Always have someone else drive you to the hospital if you are not being transported by ambulance.
If the person goes unconscious, you can start cardiopulmonary resuscitation (CPR) while you wait for emergency medical services (EMS). If you are in a public place, ask if there is an AED (automated external defibrillator) on site. An AED is a portable device that can check someone’s heart rhythm and, if necessary, deliver an electric shock to help someone who is in cardiac arrest.
What You Can Do Now
There are lifestyle changes that you can make to reduce your risk of a heart attack and increase your odds of surviving one.
According to the CDC, 47% of Americans have at least one of the three main risk factors for heart disease: high blood pressure, high cholesterol, and smoking.
Get your blood pressure and cholesterol checked regularly. If readings are high, you may be able to lower them with diet and physical activity, or your healthcare provider may recommend medications to help reduce your risk of heart attack and stroke.
In addition, these lifestyle changes can help:
Quit smoking. Eat a diet that is full of vegetables, fruits, and whole grains. Limit sweets, sugar-sweetened beverages, and red meats. Get physical activity every day. Limit alcohol.
How long does a heart attack last?
Symptoms of a heart attack can last minutes to hours, and the level of heart damage depends on how quickly treatment is received.
How do you stop a heart attack?
You cannot stop a heart attack once it is occurring. Medications and surgical procedures help restore blood flow to the heart.
Can coughing help you survive a heart attack?
This is generally not helpful, according to the American Heart Association. In a hospital setting, a nurse or other healthcare provider may instruct someone to cough forcefully and repetitively during the initial seconds of a sudden heart rhythm problem. This is to try to maintain blood flow to the brain for a few seconds. Outside of a hospital, coughing really isn’t useful and “cough CPR” is a myth.
