If you have signs or symptoms associated with acute coronary syndrome, an emergency room doctor will likely order several tests. Some tests may be done while your doctor is asking you questions about your symptoms or medical history. Tests include:

  • Electrocardiogram (ECG). Electrodes attached to your skin measure the electrical activity in your heart. Abnormal or irregular impulses can mean your heart is not working properly due to a lack of oxygen. Certain patterns in electrical signals may show the general location of a blockage. The test may be repeated several times.
  • Blood tests. Certain enzymes may be detected in the blood if cell death has resulted in damage to heart tissue. A positive result indicates a heart attack.

The information from these two tests — as well as your signs and symptoms — is used to make a primary diagnosis of acute coronary syndrome. Your doctor can use the information to determine whether your condition can be classified as a heart attack or unstable angina.

Other tests may be done to learn more about your condition, rule out other causes of symptoms, or to help your doctor personalize your diagnosis and treatment.

  • Coronary angiogram. This procedure uses X-ray imaging to see your heart's blood vessels. A long, tiny tube (catheter) is threaded through an artery, usually in your arm or groin, to the arteries in your heart. A dye flows through the tube into your arteries. A series of X-rays show how the dye moves through your arteries, revealing any blockages or narrowing. The catheter may also be used for treatments.
  • Echocardiogram. An echocardiogram uses sound waves, directed at your heart from a wand-like device, to produce a live image of your heart. An echocardiogram can help determine whether the heart is pumping correctly.
  • Myocardial perfusion imaging. This test shows how well blood flows through your heart muscle. A tiny, safe amount of radioactive substance is injected into your blood. A specialized camera takes images of the substance's path through your heart. They show your doctor whether enough blood is flowing through heart muscles and where blood flow is reduced.
  • Computerized tomography (CT) angiogram. A CT angiogram uses a specialized X-ray technology that can produce multiple images — cross-sectional 2-D slices — of your heart. These images can detect narrowed or blocked coronary arteries.
  • Stress test. A stress test reveals how well your heart works when you exercise. In some cases, you may receive a medication to increase your heart rate rather than exercising. This test is done only when there are no signs of acute coronary syndrome or another life-threatening heart condition when you are at rest. During the stress test, an ECG, echocardiogram or myocardial perfusion imaging may be used to see how well your heart works.


The immediate goals of treatment for acute coronary syndrome are:

  • Relieve pain and distress
  • Improve blood flow
  • Restore heart function as quickly and as best as possible

Long-term treatment goals are to improve overall heart function, manage risk factors and lower the risk of a heart attack. A combination of drugs and surgical procedures may be used to meet these goals.


Depending on your diagnosis, medications for emergency or ongoing care (or both) may include the following:

  • Thrombolytics (clot busters) help dissolve a blood clot that's blocking an artery.
  • Nitroglycerin improves blood flow by temporarily widening blood vessels.
  • Antiplatelet drugs help prevent blood clots from forming and include aspirin, clopidogrel (Plavix), prasugrel (Effient) and others.
  • Beta blockers help relax your heart muscle and slow your heart rate. They decrease the demand on your heart and lower blood pressure. Examples include metoprolol (Lopressor, Toprol-XL) and nadolol (Corgard).
  • Angiotensin-converting enzyme (ACE) inhibitors widen blood vessels and improve blood flow, allowing the heart to work better. They include lisinopril (Prinivil, Zestril), benazepril (Lotensin) and others.
  • Angiotensin receptor blockers (ARBs) help control blood pressure and include irbesartan (Avapro), losartan (Cozaar) and several others.
  • Statins lower the amount of cholesterol moving in the blood and may stabilize plaque deposits, making them less likely to rupture. Statins include atorvastatin (Lipitor), simvastatin (Zocor, Flolipid) and several others.

Surgery and other procedures

Your doctor may recommend one of these procedures to restore blood flow to your heart muscles:

  • Angioplasty and stenting. In this procedure, your doctor inserts a long, tiny tube (catheter) into the blocked or narrowed part of your artery. A wire with a deflated balloon is passed through the catheter to the narrowed area. The balloon is then inflated, opening the artery by compressing the plaque deposits against your artery walls. A mesh tube (stent) is usually left in the artery to help keep the artery open.
  • Coronary bypass surgery. With this procedure, a surgeon takes a piece of blood vessel (graft) from another part of your body and creates a new route for blood that goes around (bypasses) a blocked coronary artery.

Clinical trials

Explore Mayo Clinic studies testing new treatments, interventions and tests as a means to prevent, detect, treat or manage this condition.

Lifestyle and home remedies

Heart healthy lifestyle changes are an important part of heart attack prevention. Recommendations include the following:

  • Don't smoke. If you smoke, quit. Talk to your doctor if you need help quitting. Also, avoid secondhand smoke.
  • Eat a heart-healthy diet. Eat a diet with lots of fruits and vegetables, whole grains, and moderate amounts of low-fat dairy and lean meats.
  • Be active. Get regular exercise and stay physically active. If you have not been exercising regularly, talk to your doctor about the best exercise to begin a healthy and safe routine.
  • Check your cholesterol. Have your blood cholesterol levels checked regularly at your doctor's office. Avoid high-fat, high-cholesterol meat and dairy. If your doctor has prescribed a statin or other cholesterol-lowering medication, take it daily as directed by your doctor.
  • Control your blood pressure. Have your blood pressure checked regularly as recommended by your doctor. Take blood pressure medicine daily as recommended.
  • Maintain a healthy weight. Excess weight strains your heart and can contribute to high cholesterol, high blood pressure, diabetes, heart disease and other conditions.
  • Manage stress. To reduce your risk of a heart attack, reduce stress in your day-to-day activities. Rethink work habits and find healthy ways to minimize or deal with stressful events in your life. Talk to your doctor or a mental health care professional if you need help managing stress.
  • Drink alcohol in moderation. If you drink alcohol, do so in moderation. Drinking more than one to two alcoholic drinks a day can raise blood pressure.

Preparing for your appointment

If you have sudden chest pain or other symptoms of acute coronary syndrome, get emergency care immediately or call 911.

Your description of symptoms provides important information to help an emergency medical team make a diagnosis. Be prepared to answer the following questions.

  • When did signs or symptoms appear?
  • How long did they last?
  • What symptoms are you currently experiencing?
  • How would you describe the pain?
  • Where is the pain located?
  • How would you rate the severity of pain?
  • Does anything worsen or lessen the symptoms?
May 18, 2021
  1. Overview of acute coronary syndromes. Merck Manual Professional Version. https://www.merckmanuals.com/professional/cardiovascular-disorders/coronary-artery-disease/overview-of-acute-coronary-syndromes-acs. Accessed Feb. 20, 2019.
  2. Varghese T, et al. Non-ST elevation acute coronary syndrome in women and the elderly: Recent updates and stones still left unturne. F1000 Research. 2020; doi:10.12688/f1000research.16492.1.
  3. Reeder GS, et al. Initial evaluation and management of suspected acute coronary syndrome (myocardial infarction, unstable angina) in the emergency room. https://www.uptodate.com/contents/search. Accessed Feb. 20, 2019.
  4. Ischemic heart disease. National Heart, Lung, and Blood Institute. https://www.nhlbi.nih.gov/health-topics/ischemic-heart-disease. Accessed Feb. 20, 2019.
  5. Myocardial perfusion imaging (MPI) test. American Heart Association. https://www.heart.org/en/health-topics/heart-attack/diagnosing-a-heart-attack/myocardial-perfusion-imaging-mpi-test#.VtMi8xh4yPU. Accessed Feb. 20, 2019.
  6. Soman P, et al. Noninvasive testing and imaging for diagnosis in patients at low to intermediate risk for acute coronary syndrome. https://www.uptodate.com/contents/search. Accessed Feb. 20, 2019.
  7. Cardiac medications. American Heart Association. http://www.heart.org/HEARTORG/Conditions/HeartAttack/%20PreventionTreatmentofHeartAttack/Cardiac-Medications_UCM_303937_Article.jsp#.XG37pKJKjIU. Accessed Feb. 20, 2019.
  8. Guedeney P, et al. Diagnosis and management of acute cornary syndrome: What is new and why? Insight from the 2020 European Society of Cardiology Guidelines. Journal of Clinical Medicine. 2020; doi:10.3390/jcm9113474.
  9. Cardiac procedures and surgeries. American Heart Association. https://www.heart.org/en/health-topics/heart-attack/treatment-of-a-heart-attack/cardiac-procedures-and-surgeries#.VtMj5hh4yPU. Accessed Feb. 20, 2019.