What is the Difference Between STEMI and NSTEMI

The key difference between STEMI and NSTEMI is that STEMI occurs due to a total blockage of one of the main coronary arteries, while NSTEMI occurs due to a partial blockage of a coronary artery or a blockage in a branch off of the main coronary artery.

STEMI and NSTEMI are two different types of heart attacks. Both these types occur due to the blockage of the coronary artery. Any heart attack is a life-threatening medical emergency and needs medical care immediately. Delaying a medical emergency can be extremely dangerous and can also lead to permanent heart damage or death.

1. Overview and Key Difference
2. What is STEMI
3. What is NSTEMI
4. Similarities – STEMI and NSTEMI
5. STEMI vs NSTEMI in Tabular Form
6. Summary – STEMI vs NSTEMI

What is STEMI?

STEMI is a type of heart attack that occurs because of a total blockage in one of the main coronary arteries. It is also known as ST-elevation myocardial infarction. This type of heart attack has a greater risk of serious complications and death. STEMI heart attack causes distinct changes in the pattern of an electrocardiogram (ECG). It causes an elevation in the ST segment of an ECG. Normally, there should not be any electrical activity or elevation in the ST segment of an ECG. This change means that there is a total blockage in one of the main supply arteries (coronary arteries) in the heart. Moreover, this can be a sign of dying muscles in the ventricles. Ultimately, the heart cannot pump enough blood to support the body. The causes of STEMI include the build-up of plaque, drugs such as cocaine and excessive alcohol use, smoking, high blood pressure, high cholesterol, diabetes, obesity, overexertion, and stress.

The risk factors that can increase STEMI include tobacco smoking, diet (high sodium, sugar, and cholesterol), low level of physical activities, alcohol use, drug use, older age, sex (men’s heart attack risk starts at 45 and women’s heart attack risk start at 55), family history, and genetic or congenital conditions. There are about 28,000 people suffering from STEMI each year in the U.S. The common symptoms of this condition may include chest pain, shortness of breath, nausea, stomach pain, heart palpitation, anxiety, sweating, feeling dizzy, lightheadedness, or fainting.

STEMI can be diagnosed through physical signs, electrocardiograms (EKG), CT scans, MRI, lab testing for a chemical called troponin, coronary angiography, and radionuclide imaging (thallium stress test). Furthermore, the treatment options for STEMI include percutaneous coronary intervention (PCI), medications such as beta-blockers, statins, aspirins, antiplatelet medications, anticoagulants, nitroglycerin, pain medications (morphine), oxygen therapy, coronary artery bypass grafting (CABG) surgery, and cardiac rehabilitation program.

What is NSTEMI?

Non-ST elevation myocardial infarction (NSTEMI) is a type of heart attack that occurs due to a partial coronary artery blockage or blockage in a branch off of the main coronary artery. People who have NSTEMI don’t have ST elevation in the ECG, and this is a less severe condition compared to STEMI. However, in rare cases, some electrical patterns may be visible with NSTEMI, but they are often considered as not distinctive. The signs and symptoms of this condition may include chest pain, trouble breathing, nausea, vomiting, stomach discomfort or pain, heart palpitation, lightheadedness, dizziness, passing out, and excessive sweating. The causes of NSTEMI include plaque, vasospasm, coronary embolism, myocarditis, poison and toxins, cardiac contusion, severe high blood pressure, tachycardia, aortic stenosis, and pulmonary embolism. The risk factors for NSTEMI include tobacco smoke, diet (high sodium, sugar, and cholesterol), lower level of physical activity, recreational drug use, older age, sex (men’s heart attack risk starts at 45 and women’s heart attack risk starts at 55), family history and inherited or condition present at birth.

Approximately 546000 NSTEMI cases are reported yearly in U.S. NSTEMI can be diagnosed through physical signs, electrocardiogram (EKG or ECG), lab testing for troponin, white blood cell count, echocardiography, CT scan, and MRI. Furthermore, treatment options for NSTEMI include percutaneous coronary intervention (PCI), medications (aspirin, anticoagulants, angiotensin-converting enzyme inhibitors, beta-blockers, nitroglycerin, and satins), coronary artery bypass grafting (CABG), treating underlying conditions (diabetes, cholesterol or high blood pressure), lifestyle and home remedies (consuming a nutritious and balanced diet, reducing and limiting food that contain saturated and trans fat, exercising at least 30 minutes, managing stress level, quitting smoking, and managing a moderate weight).

What are the Similarities Between STEMI and NSTEMI?

STEMI and NSTEMI are two different types of heart attacks.
Both these types occur due to coronary artery blockage.
They are life-threatening medical emergencies.
They have the same risk factors.
If not treated immediately, they can lead to complications and death.
Both these types can be diagnosed through an electrocardiogram, blood tests, and imaging tests.
They are treated through specific medications and surgeries.

What is the Difference Between STEMI and NSTEMI?

STEMI is a type of heart attack that happens because of a total blockage of one of the main coronary arteries, while NSTEMI is a type of heart attack that happens because of a partial coronary artery blockage or blockage in a branch off of the main coronary artery. So, this is the key difference between STEMI and NSTEMI. Furthermore, there are about 28,000 people who suffer from STEMI each year in the U.S. On the other hand, there are about 546,000 people who suffer from NSTEMI each year in the U.S.

The below infographic presents the differences between STEMI and NSTEMI in tabular form for side-by-side comparison.

Summary – STEMI vs NSTEMI

STEMI and NSTEMI are two different types of heart attacks. Both these conditions occur due to blockages in the coronary arteries. STEMI happens because of a total blockage of one of the main coronary arteries. It poses a greater risk of serious complications and death. On the other hand, NSTEMI happens because of a partial coronary artery blockage or blockage in a branch off of the main coronary artery. It is a less severe condition compared to STEMI. Thus, this summarizes the difference between STEMI and NSTEMI.

Reference:

1. “What Is a Stemi Heart Attack?” Cleveland Clinic.
2. “NSTEMI: Treatment, Symptoms, and Diagnosis.” Medical News Today, MediLexicon International.

Image Courtesy:

1. “Flipped Posterior STEMI ECG” By Life in the Fastlane (CC BY-SA 4.0) via Commons Wikimedia
2. “ACS scheme” By User:Stevenfruitsmaak – Own work (CC BY-SA 3.0) via Commons Wikimedia