Heart Attack Treatment Guidelines
The American College of Cardiology and the American Heart Association, in collaboration with the Society for Cardiovascular Angiography and Intervention, and the American Association of Cardiovascular and Pulmonary Rehabilitation, have developed a series of guidelines that address the treatment of heart attack. These guidelines apply to most patients, but also give your doctor the flexibility to tailor treatment to your specific clinical needs. Below is a summary of key information and recommendations:
Early hospital care
When you arrive at the hospital you will:
- Have blood tests called cardiac biomarkers to check for damage to your heart muscle
- Have an electrocardiogram (ECG) to evaluate your heart’s rhythm and look for abnormalities in the heart’s electrical system
- Be treated with several medications that protect your heart and relieve pain. These may include a beta blocker, nitroglycerin, and morphine. You will also be given an aspirin tablet to chew, if you haven’t taken one already.
- If your heart stopped beating during or after your heart attack (cardiac arrest), your doctor may use a treatment called therapeutic hypothermia. This involves infusion of a liquid into your blood vessels that cools your body to about 90 degrees Fahrenheit for up to 24 hours. Cooling your body will help protect against brain damage that can occur when the brain is deprived of blood during cardiac arrest.
The next steps in your treatment will depend on what type of heart attack you are having. There are two types, STEMI, which is short-hand for “ST-elevation myocardial infarction,” and NSTEMI, which stands for “non-ST-elevation myocardial infarction.” The names reflect differences in the ECG tracings—specifically whether a portion of the ECG called the ST segment is elevated above baseline, or not. More important, there are differences in the underlying cause of these two types of heart attack and, therefore, in the initial treatment.
A STEMI heart attack is caused when a blood clot suddenly forms, completely blocking an artery in the heart. This can result in damage that covers a large area of the heart and extends deep into the heart muscle. The priority in treating a STEMI heart attack is to open the artery quickly, saving as much heart muscle as possible. Treatment options include percutaneous coronary intervention (PCI), a term that encompasses both angioplasty and stenting; clot-busting medication; and coronary artery bypass graft surgery (CABG).
PCI is the first choice for the treatment of STEMI, if it is available. The goal is to open the artery within 90 minutes of the patient first receiving care by emergency medical workers, including ambulance personnel.
If your hospital does not have a PCI program, the next best option may be rapid transfer to a nearby medical center that is experienced and prepared to use PCI to treat heart attack. The goal in this case is to open the artery within 2 hours of the patient first receiving care by emergency medical workers.. In many areas of the country, regional STEMI networks are being set up to make transport to a PCI hospital fast and efficient.
Most hospitals don’t have a cardiac catheterization laboratory available 24 hours a day to treat heart attack patients. If you seek emergency treatment at a hospital that isn’t equipped to perform PCI, and the nearest PCI-capable hospital is too far away to meet the goal of opening the artery within 2 hours, clot-busting medications are an effective treatment option. These medications, also called fibrinolytics, open the artery by dissolving the clot. The goal is to infuse clot-busting medications within 30 minutes of a patient’s arrival at the hospital.
In some cases, your doctor may decide that you should have PCI in addition to treatment with clot-busting medication. With this “pharmacoinvasive strategy,” clot-busting medication is used at the first hospital to initially restore blood flow to your heart, then after transport to a PCI-capable hospital, PCI is performed within 24 hours to make sure the artery is fully open and supported with a stent.
Coronary Artery Bypass Graft Surgery (CABG)
In some cases, emergency bypass surgery may be the best option, especially if you are medically unstable and cannot be treated with PCI or clot-busting medications, or when these treatments fail. Emergency CABG may also be needed if serious complications develop after a heart attack, such as shock, life-threatening abnormalities of the heart rhythm, or rupture of heart tissues. Your doctor may also recommend having CABG surgery within the first 2 days of a heart attack if you have several clogged arteries and start experiencing a return of chest pain while resting quietly.
NSTEMI heart attacks are different from STEMI heart attacks in several ways, not just how they appear on the ECG. With NSTEMI, the heart attack damage usually doesn’t extend through the full depth of the heart muscle. Equally important, NSTEMI heart attacks are caused by different types of blood clots than STEMI heart attacks, with differing amounts of clotting proteins and platelet blood cells. Therefore, the treatment of NSTEMI heart attacks differs from the treatment of STEMI heart attacks. Clot-busting medications, for example, are not effective, and although PCI may be part of the treatment, opening the artery within 90 minutes is not a primary goal.
Diagnosis of NSTEMI can be complex, as the diagnostic signs don’t always show up right away. Your doctor may repeat the ECG and cardiac biomarker blood tests several times, and carefully analyze the pattern and severity of your chest pain, your other symptoms, and your history of heart disease to determine your level of risk. You may be transferred to a special chest pain unit for observation for several hours. After that, if your chest pain has not returned and the diagnosis is still unclear, your doctor may order an imaging test of your heart (a nuclear scan, a type of ultrasound known as echocardiography, or a treadmill stress test). This will help to determine a final diagnosis.
Once the diagnosis of NSTEMI has been made, you will be admitted to the hospital. Medications to protect your heart and reduce its workload (beta blockers, nitroglycerin, and possibly an angiotensin-converting-enzyme (ACE) inhibitor or angiotensin-receptor blocker) will be continued. Your doctors will also add one or more anti-clotting medications to prevent blood clots.
Within the first 12 to 24 hours of your hospital stay, your doctor will select one of two main treatment strategies. One option is continued treatment with medications that protect your heart, reduce its workload, and prevent blood clots. This is a reasonable strategy if your condition is stable and you are not at high risk for serious cardiac complications.
The second treatment option is an “early invasive” strategy. This means that you will go to the cardiac catheterization laboratory for angiography, a procedure that enables your doctor to see inside the arteries of your heart. Usually angiography is followed by PCI and stenting to widen clogged, inflamed portions of the arteries where blood clots may have formed. The “invasive” strategy is a reasonable option if you are continuing to have chest pain, are medically unstable, or have a high-risk history of heart disease.
During your hospital stay
Whether you have a STEMI or NSTEMI heart attack, you will begin to take steps toward recovery and a healthy new lifestyle while you’re still in the hospital. You will learn about your medications and begin eating a heart-healthy diet that is low in sodium, cholesterol, and fat (especially “saturated” animal fats). As soon as it is safe, you will also begin mild exercise, such as walking in the hallway. In addition, your doctor will refer you to a cardiac rehab program, so that you can continue
You may have an imaging test while in the hospital, or shortly after discharge, to evaluate how efficiently your heart is pumping blood. This information, known as the ejection fraction or systolic function, will guide your doctor in prescribing medications and other treatments.
Discharge from the hospital
When you are ready to go home, you will be prescribed several medications that have been proven to protect the heart, help it to function better, and prevent repeat heart attacks. Your medications will include some or all of the following:
- Aspirin, to keep platelets in the blood from clumping together and forming blood clots
- Another anti-clotting medication such as clopidogrel or prasugrel, or ticagrelor. How much anti-clotting medication you take, which specific drug, and how long you take it will depend on your medical condition and whether you were treated with a stenting procedure.
- Beta blocker
- Cholesterol-lowering therapy
- Angiotensin-converting-enzyme (ACE) inhibitor or angiotensin-receptor blocker (ARB), if your heart is not pumping as strongly as it should
Certain medications used to treat heartburn—called proton pump inhibitors—may reduce the effectiveness of anti-clotting medications. Talk to your doctor about what type of heartburn medication is safe to use.
Staying healthy after the hospital
Participating in a cardiac rehabilitation program a high priority for anyone who has had a heart attack. Not only will cardiac rehab help you to feel healthy and strong again, it can actually help you to live longer. Your cardiac rehab program will teach you to:
- Stop smoking and/or using tobacco products
- Follow a heart-healthy diet
- Exercise safely, guided by specially trained physical therapists, nurses, and doctors
- Manage stress and anxiety
- Safely resume your sex life
- Avoid a second heart attack
In addition to participating in a cardiac rehab program, the following steps will help prevent a second heart attack and keep your arteries from becoming clogged with atherosclerotic plaque:
- Quit smoking, and avoid second-hand smoke
- Keep blood pressure under 140/90 mmHg (or lower, if you have diabetes or heart failure)
- Keep LDL (“bad”) cholesterol under 100 mg/dL, or under 70 mg/dL if you are at high risk. This is generally accomplished through the use of statin medications.
- Exercise for 30 to 60 minutes at least 5 days a week. The exercise should be moderate-intensity, such as brisk walking.
- Maintain a normal body weight
- Maintain good diabetes control
- Take low-dose aspirin daily to prevent unwanted blood clots, plus additional anti-clotting medication if advised by your doctor
- Take an ACE inhibitor or ARB, if your heart’s pumping ability is abnormal or you have heart failure
- Take beta blockers to protect the heart and reduce its workload
- Get an annual flu shot
- Seek treatment for depression
Read the full guidelines in the Journal of the American College of Cardiology