Unstable angina or sometimes referred to as acute coronary syndrome causes unexpected chest pain, and usually occurs while resting. The most common cause is reduced blood flow to the heart muscle because the coronary arteries are narrowed by fatty buildups (atherosclerosis) which can rupture causing injury to the coronary blood vessel resulting in blood clotting which blocks the flow of blood to the heart muscle.

Signs / Symptoms

What's common signs of unstable angina pectoris?

Unstable angina is a type of angina (chest pain) that often doesn’t have a pattern and usually gets worse. It happens with only mild physical activity or may happen without warning when you’re at rest, relaxing or even asleep.

  • Chest pain; That happens without warning, can happen even if you’re resting or sleeping.Doesn’t last the same amount of time (and can last a long time) or has the same cause each time.
  • Chest pain that feels crushing, pressure-like, squeezing, or sharp. Pain that radiates to your upper extremities (usually on the left side) or back.
  • Chest pain that doesn’t stop after taking medicine
  • Comes as a surprise
  • May get worse overtime
  • Shortness of breath

Common causes

What's common causes of unstable angina pectoris?


It’s possible for stable angina to progress to unstable angina. If you have stable angina, be aware of any chest pains you feel even when at rest. Also watch for chest pains that last longer than they typically do or that simply feel different to you.

  • Coronary artery disease due to atherosclerosis is the most common cause of unstable angina.
  • It’s possible for stable angina to progress to unstable angina.
  • Coronary artery spasms cause a rare type of unstable angina called variant or Prinzmetal angina
Risk factors for coronary artery disease include:
  • Diabetes
  • Family history of early coronary heart disease (a close relative such as a sibling or parent had heart disease before age 55 in a man or before age 65 in a woman)
  • High blood pressure &
  • High cholesterol levels
  • Male sex
  • Sedentary lifestyle (not getting enough exercise)
  • Obesity
  • Older age
  • Smoking

Departments & Emergency

Unstable angina should be treated as an emergency. If you have new, worsening or persistent chest discomfort, you need to go to the ER. You could be having a heart attack which puts you at increased risk for severe cardiac arrhythmias or cardiac arrest, which could lead to sudden death. When you enter an ER there will be cardiologists and/or cardiothoracic surgeons taking care of you as well as emergency medicine doctors.


Your doctor will perform a physical exam that includes checking your blood pressure. They may use other tests to confirm unstable angina, such as:

  • Blood tests to check for creatine kinase and cardiac biomarkers
  • Electrocardiogram
  • Echocardiography
  • Coronary angiography and heart catheterization
  • Computed tomography angiography


You may need to check into the hospital to get some rest, have more tests, and prevent complications.

  • Medication: One of the first things your physician will order is blood thinners. Later on you may use drugs that reduce blood pressure, arrhythmia symptoms, anxiety, cholesterol levels
  • Supplemental oxygen
  • Lifestyle changes
  • Surgery

Aspirin: for its antiplatelet therapies,
Nitroglycerin: improved perfusion by vasodilation of the coronaries allowing improved flow and improved blood pressure
Clopidogrel: is an option for patients not able to tolerate aspirin.



Before any of these procedures, your doctor must find the blocked part or parts of the coronary arteries.

A procedure called angioplasty and stenting can often be done to open a blocked or narrowed artery.

  • Angioplasty is a procedure to open narrowed or blocked blood vessels that supply blood to the heart.
  • A coronary artery stent is a small, metal mesh tube that opens up (expands) inside a coronary artery. A stent is often placed after angioplasty. It helps prevent the artery from closing up again. A drug-eluting stent has medicine in it that helps prevent the artery from closing over time.

Heart bypass surgery may be done for some people. The decision to have this surgery depends on:

  • Which arteries are blocked
  • How many arteries are involved
  • Which parts of the coronary arteries are narrowed
  • How severe the narrowings are


What is the difference between stable angina and unstable angina?

With stable angina, the chest pain or other symptoms only occur with a certain amount of activity or stress. The pain does not occur more often or get worse over time.Unstable angina is chest pain that is sudden and often gets worse over a short period of time. Unstable angina is a warning sign that a heart attack may happen soon and needs to be treated right away. See your health care provider if you have any type of chest pain.


How long can you live with unstable angina?

How well you do depends on many different things, including:

  • How many and which arteries in your heart are blocked, and how severe the blockage is
  • If you have ever had a heart attack
  • How well your heart muscle is able to pump blood out to your body

Evidence shows that patients with new-onset ST-segment elevation (more than 1 mm) have a 12-month rate of an MI or death of about 11%, compared to only 7% for patients who only have isolated inversion of the T wave.


How do you manage unstable angina?

The mainstay of treatment focuses on improving perfusion of the coronary arteries.This is done in several ways. Medication, surgery, minimally invasive procedures. Lifestyle changes that can improve your heart healthYour provider will also recommend that you keep other health conditions such as high blood pressure, diabetes, and high cholesterol levels under control.



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