What is an NSTEMI?

An NSTEMI, or non-ST-elevation myocardial infarction, is a type of heart attack. An NSTEMI occurs when a partial blockage of a coronary artery or a temporary disruption of blood flow prevents the heart from getting enough oxygen.

As the heart is deprived of oxygen, the heart muscle begins to deteriorate. The longer the heart goes without oxygen, the more damage occurs.

This type of heart attack gets its name from the fact that it doesn’t show an identifiable ST-segment elevation on an electrocardiogram, which is a sign of a complete blockage of the coronary artery. The ST elevation is a pattern of electrical signals in the heart.

Each year in the United States, more than 800,000 people experience a heart attack, and the vast majority of those are NSTEMIs.

NSTEMI vs. STEMI heart attacks

NSTEMI and STEMI (ST-elevation myocardial infarction) are both types of heart attacks. The difference between the two is that a STEMI heart attack causes ST-segment elevation on an EKG, while an NSTEMI does not.

A STEMI heart attack occurs when a coronary artery is completely blocked, which is what causes the ST segment to elevate on an EKG. An NSTEMI heart attack occurs when there’s a partial blockage or temporary disruption of blood flow, which shows up differently on an EKG, with more subtle changes.

Illustration of an artey that is patrially blocked of blood flow. NSTEMI heart attacks occur when a

NSTEMI symptoms

Symptoms of NSTEMI are the same as for other types of heart attacks. NSTEMI causes chest pain that may feel more like pressure, often occurs when you’re at rest and usually lasts more than 10 minutes. The pain may travel from your chest down one or both arms or to your neck or jaw.

You may have these other NSTEMI symptoms along with chest pain:

  • Excessive sweating
  • Fainting
  • Feeling very tired
  • Nausea or vomiting
  • Shortness of breath

Women, people older than age 75 and those with diabetes, dementia and kidney disease are more likely to experience “atypical” symptoms during an NSTEMI, such as stabbing chest pain, abdominal pain and indigestion.

When to see a doctor

Call 911 if you experience symptoms of an NSTEMI or other type of heart attack. When a heart attack occurs, minutes matter. While you’re in transit to the hospital, the crew of emergency medical technicians can stabilize you and ensure you get the care you need as quickly as possible once you arrive at the hospital.

NSTEMI causes

NSTEMI is considered an acute coronary syndrome, an umbrella term for conditions that suddenly limit oxygen to the heart. Acute coronary syndromes occur when the heart needs more oxygen than it receives. With NSTEMI, many conditions can directly or indirectly limit the heart’s oxygen supply.

Conditions that can directly limit oxygen include:

  • A blood clot that partially or completely cuts off blood flow to the heart
  • Atherosclerosis (plaque buildup along the coronary artery walls)
  • Exposure to toxic chemicals
  • An injury that bruises the heart (cardiac contusion)
  • Myocarditis (inflammation related to an infection)
  • Spasms in the muscle lining of the coronary arteries (vasospasms)

Indirect causes of NSTEMI also prevent oxygen but usually in ways other than direct blockage or injury. They include:

  • Aortic stenosis: This is the narrowing of one of your heart’s four valves. The condition can restrict blood flow and oxygen to your organs, muscles and tissues.
  • High blood pressure: High blood pressure can cause arteries to harden, increasing the demands on the heart while limiting the heart’s ability to deliver oxygen.
  • Low blood pressure: Low blood pressure could prevent your heart from getting enough oxygen-rich blood.
  • Tachycardia: Tachycardia is a fast heartbeat. When the heart beats too quickly, it may struggle to pump enough oxygen-rich blood.

NSTEMI risk factors

While anyone of any age can have an NSTEMI heart attack, they’re most common in older men. A condition considered an indirect cause of oxygen deprivation in your heart increases your risk, as do other health conditions and certain lifestyle behaviors. Although you can’t control all your risk factors, knowing which ones you can change allows you to take steps to lower your risk.

Risk factors for NSTEMI include:

  • Advanced age: The older you are, the higher your risk. The average age for acute coronary syndrome, such as an NSTEMI, is 68.
  • Certain health conditions: Diabetes, kidney failure, hypertension, hyperlipidemia and obesity increase the risk of atherosclerosis and cause inflammation, which increases the risk of NSTEMI.
  • Family history: Your heart attack risk is higher if you have family members with heart problems, especially a heart attack or other diagnosis at an early age.
  • Lifestyle habits: Smoking or using other forms of tobacco, physical inactivity, using recreational drugs and eating an unhealthy diet can contribute to atherosclerosis.
  • Male sex: Males are more likely to have acute coronary syndrome.

Complications

The most common impact of an NSTEMI heart attack is the damage done to the heart muscle while it’s deprived of blood and oxygen. Less commonly, an NSTEMI heart attack can also cause complications with the heart and other systems in the body, including:

  • Cardiomyopathy: This condition weakens your heart’s ability to pump blood and can cause its own complications, including arrhythmias and heart failure.
  • Pulmonary edema: An accumulation of fluid in the air sacs of the lungs, this condition limits your ability to breathe and can be very serious.

Diagnosing an NSTEMI

NSTEMIs are medical emergencies usually diagnosed and initially treated in the emergency room. To determine if you’re having an NSTEMI heart attack, doctors will use several tools, including a thorough medical exam, an electrocardiogram and blood tests to look at cardiac biomarkers.

Together, these tests can confirm whether you’re having a heart attack and, if so, whether it’s an NSTEMI or STEMI.

NSTEMI treatment

Treatment for an NSTEMI heart attack includes two components: immediate treatment to restore blood flow and limit damage to the heart and ongoing treatment to help your heart recover and prevent future heart attacks.

Your primary care or emergency doctors may recommend seeing a cardiologist who has specialized expertise in treating heart attacks and underlying heart conditions.

Surgery

If tests reveal blockages in the coronary arteries as the cause of an NSTEMI heart attack, your doctor may recommend surgery to treat or remove the blockage:

  • Angioplasty and percutaneous coronary intervention (PCI): This minimally invasive procedure uses a balloon to push plaque against your artery walls and keep the artery open with a mesh tube called a stent.
  • Coronary artery bypass grafting (CABG): CABG, or heart bypass, can treat severe or multiple coronary artery blockages. An open-heart procedure, CABG involves using a healthy blood vessel from another part of the body to bypass a blockage.

Locations for NSTEMI care

Our cardiologists and emergency teams are dedicated to helping you recover from a heart attack as quickly and thoroughly as possible. Find high-quality emergency and follow-up heart care at locations across Texas.

Frequently asked questions

Loading...