Diseases & Conditions


Acute Coronary Syndrome

Diseases & Conditions


What is acute coronary syndrome?

Acute coronary syndrome is an umbrella term for any condition characterized by a reduced flow of blood to the heart. Acute coronary syndrome includes many conditions such as unstable angina and heart attack. These conditions happen when the coronary arteries of the heart that supply oxygen-rich blood are blocked and hence, the heart does not get enough oxygen.1


What causes acute coronary syndrome?

Most cases of acute coronary syndrome are caused by the build-up of cholesterol in the arteries forming atherosclerotic plaques. The accumulation of plaques results in narrowing the blood vessels supplying the heart. This will limit the oxygen from reaching to the rest of the body causing chest pain (angina) or a heart attack.2


What are the risk factors for acute coronary syndrome?

Acute coronary syndrome risk factors include:3

  • Age: Men older than 45 and women older than 55 are at increased risk of developing acute coronary syndrome
  • Hypertension
  • High blood cholesterol levels
  • Smoking
  • Physical inactivity
  • Type 2 diabetes mellitus
  • Family history of chest pain, heart disease or stroke
  • A history of hypertension, preeclampsia or gestational diabetes for women


What are the symptoms of acute coronary syndrome?

Symptoms of acute coronary syndrome include:4

  • Angina which is characterized by a chest pain, pressure, or a strange feeling in the chest.
  • Pain or pressure in the back, neck, jaw, or upper belly, or in one or both shoulders or arms
  • Sweating
  • Shortness of breath
  • Nausea
  • Vomiting
  • Sudden weakness
  • A fast or irregular heartbeat


How is acute coronary syndrome diagnosed?

Several tests are required to diagnose acute coronary syndrome:5

  • Blood tests: If the heart is damaged by a heart attack, it leaks into the blood certain enzymes that can be detected by a blood test.
  • Electrocardiogram (ECG or EKG): This test records the electrical activity of the heart which can detect heart problems.
  • Echocardiogram: This test produces an image of the heart which can identify if an area of the heart is damaged.
  • Chest X-ray: The shape and size of the heart as well as the blood vessels can be visualized with a chest X-ray.
  • Nuclear scan: This test uses radioactive material injected into the bloodstream that can identify blood flow problems.
  • Computerized tomography (CT) angiogram: This test allows the doctor to check whether the arteries are blocked or narrowed.
  • Coronary angiogram (cardiac catheterization): This test can check blood flow in the coronary arteries.
  • Exercise stress test: This test involves exercising like walking on a treadmill to increase the heart rate while an electrocardiogram, heart rate and blood pressure are monitored.


How is acute coronary syndrome treated?

Treatment for acute coronary syndrome includes a set of medications administered depending on the symptoms and to what extent the arteries are blocked.6

  • Medications:
    • Nitroglycerin: Nitroglycerin dilates the large coronary arteries improving the blood flow.
    • Morphine and other analgesics
    • β-blockers: These drugs help relax the heart muscle, slow the heart rate and decrease blood pressure.
    • Calcium channel blockers: Calcium channel blockers inhibit the contraction of the heart and hence decrease the oxygen demand.
    • Antithrombotic therapy: These medications help prevent blood clots from forming by reducing platelet activation and aggregation.
    • Antiplatelet therapy: Aspirin for example decreases blood clotting and allows blood to flow through narrowed arteries.
    • Lipid-lowering therapy: Lipid-lowering therapy such as statins should be initiated for all patients in order to decrease cholesterol levels and plaques formation.



  1. Acute Coronary Syndrome. Heart condition health information | Patient (Patient) http://patient.info/health/acute-coronary-syndrome-leaflet (Accessed January 10, 2016)
  2. Acute Coronary Syndrome: Healthwise Medical Information on eMedicineHealth (eMedicineHealth) http://www.emedicinehealth.com/acute_coronary_syndrome-health/article_em.htm (Accessed January 10, 2016)
  3. Acute Coronary Syndrome (Acute Coronary Syndrome) http://www.heart.org/HEARTORG/Conditions/HeartAttack/AboutHeartAttacks/Acute-Coronary-Syndrome_UCM_428752_Article.jsp#.VpHshMZ97IU (Accessed January 10, 2016)
  4. Acute Coronary Syndrome-Topic Overview (WebMD) http://www.webmd.com/heart-disease/tc/acute-coronary-syndrome-topic-overview (Accessed January 10, 2016)
  5. Acute coronary syndrome (Tests and diagnosis) http://www.mayoclinic.org/diseases-conditions/acute-coronary-syndrome/basics/tests-diagnosis/con-20033942 (Accessed January 10, 2016)
  6. Kumar, Amit, and Christopher P. Cannon. "Acute coronary syndromes: diagnosis and management, part I." Mayo Clinic Proceedings. Vol. 84. No. 10. Elsevier, 2009.