What is an NSTEMI?

A Non-ST-Elevation Myocardial Infarction is a type of heart attack, often referred to as NSTEMI or a non-STEMI. In medical terminology, a heart attack is a myocardial infarction. An NSTEMI is a less severe form of heart attack than the STEMI because it inflicts less damage to the heart. However, both are heart attacks and require immediate medical care.

Causes

There are several possible NSTEMI causes and risk factors:

• Use of tobacco products
• High blood pressure
• Low level of physical activity
• High rate of cholesterol
• Presence of diabetes
• Genetics (family history of heart disease or stroke)
• Obesity or overweight body type
• History of certain medical conditions:
• Angina (chest pain)
• Myocardial infarction (heart attack)
• Stroke (interruption of blow flow to the brain)
• Transient ischemic attack (temporary condition with stroke symptoms)
• Peripheral vascular disease (circulatory condition)

Symptoms

NSTEMI produces several symptoms similar to other conditions. Any symptoms associated with a heart attack are serious. Anyone experiencing any of the NTEMI symptoms should contact 911 or visit an emergency room immediately, regardless of severity. With heart attacks, every minute counts. The faster you receive treatment, the less damage to your heart. Symptoms of NSTEMI:

• Difficulty or trouble breathing
• Heaviness or pressure in your chest
• Tension or tightness in your chest
• Discomfort in your chest
• Pain or irritation in your neck
• Pain or irritation in your stomach
• Pain or irritation in your jaw
• Pain or irritation in your back
• Feeling of nausea or queasiness
• Feeling of lightheadedness
• Feeling of dizziness
• Increased sweating (unexplained)

Diagnosis

NSTEMI heart attacks are diagnosed through the combination of a blood test and an electrocardiogram (ECG). Doctors use the blood test to look for indications of NSTEMI, such as higher than usual levels of creatine kinase-myocardial band (CK-MB), troponin I, and troponin T.

Blood tests alone are not enough data to confirm a diagnosis. Therefore, your doctor will follow blood tests with an electrocardiogram (ECG) heart tracing examination. Heartbeats show up as wavy lines on the ECG. Doctors study the waveforms for the distinct patterns and features of an NSTEMI. These wave patterns also reveal whether or not a heart attack occurred.

Wave characteristics of an NSTEMI ECG:

• Depressed ST wave or T-wave downturn (looks like a dip in the wave)
• No advancement to Q wave
• Partial obstruction of the coronary artery

Treatment

Non-ST-Segment Elevation Myocardial Infarction (NSTEMI) treatment varies based on individual characteristics, medical history, gravity of the condition and the degree of obstruction in the coronary artery.

Your doctor will determine the severity of the heart attack by giving you a GRACE Score (also known as the GRACE risk score). The GRACE score is based on a 10-year research study that resulted in the creation of the Global Registry of Acute Coronary Events (GRACE) and the GRACE Score. This score determines three levels of risk: low, medium, and high.

Factors of a GRACE Score

The following are factors of a GRACE Score:

• Age of the patient
• Systolic blood pressure (the force of your heartbeat on your blood vessels)
• Heart rate (normal, slow, fast, erratic)
• Serum creatinine level (high levels are associated with kidney damage)
• Whether there was a cardiac arrest on hospital admission (cardiac arrest means heart failure)
• ST-segment deviation in their ECG (indication of NSTEMI)
• Elevated cardiac marker
• Signs of heart malfunction (usually found during a physical exam)

Based on your GRACE Score, your doctor will generally recommend additional NSTEMI treatment. Additional treatments include medication (for low risk patients) and potential surgery (for medium to high risk patients).

If you are found to be at low risk, you may be prescribed the following medication:

• Anticoagulants (prevent blood from clotting)
• Antiplatelets (thins the blood)
• Beta-blockers (slows down the heart rate)
• Nitrates (provides relief to chest pain)
• Statins (cholesterol medication)
• Angiotensin-converting-enzyme (ACE) inhibitors (reduces the swelling of the heart)
• Angiotensin receptor blockers (ARBs) (lowers chemicals in your body that constrict blood vessels)

If you are found to be at medium or high risk, your doctor may recommend one of the following surgeries:

• Percutaneous coronary intervention (PCI) – This is a procedure to open blocked arteries in the heart. Your doctor will use a miniature balloon catheter to widen the arteries and free blood flow to the heart.
• Coronary artery bypass graft (GABG) – In this procedure, your doctor will use a blood vessel from another part of your body (leg or chest, for example) to bypass the blocked vessel so that blood reaches your heart.