Each year, millions of people are impacted by various forms of coronary artery diseases, collectively referred to as acute coronary syndrome (ACS). These potentially life-threatening conditions arise when blockages in the arteries halt or disrupt the necessary blood flow to the heart.
Acute Coronary Syndrome encompasses conditions like unstable angina, non-ST elevation myocardial infarction (NSTEMI), and ST-elevation myocardial infarction (STEMI).
What Causes Acute Coronary Syndrome (ACS)?
Heart muscles need a constant supply of oxygen-rich blood to function properly. The most common cause of a blocked coronary artery is the formation of a blood clot and fatty deposits (plaque) within the artery walls.
Here’s a deeper dive:
ACS generally arises due to plaque buildup within the coronary arteries, the vessels that provide oxygen and essential nutrients to heart muscles. This plaque formation can lead to the development of blood clots that obstruct blood flow to cardiac tissues.
The deprivation of oxygen can cause cardiac muscle cells to die. This cell death resulting in damage to muscle tissues is known as a myocardial infarction or heart attack. In instances where there’s no cell death, the lack of oxygen still impairs the heart muscles’ function, which can be either temporary or permanent. This condition is termed as stable angina when it doesn’t result in cell death.
Types of Acute Coronary Syndrome
ACS constitutes three forms of coronary artery disease that can impair, damage, or destroy heart tissues. The nature of the condition is determined by:
- The location of the blood blockage in your heart.
- The duration of the obstruction.
- The extent of the damage caused.
Here’s a closer look at the three types of acute coronary syndrome:
Unstable Angina. This condition causes sudden and unexpected chest pressure or pain, even when you are resting. It signifies a deterioration of stable angina and serves as a warning sign of an impending heart attack.
Non-ST-elevation Myocardial Infarction (NSTEMI). Identifiable only through blood tests and not an electrocardiogram (EKG), an NSTEMI indicates a partial blockage in the coronary arteries.
ST-elevation Myocardial Infarction (STEMI). A more severe form of a heart attack, STEMI can be diagnosed using both blood tests and EKGs. It occurs due to a prolonged and complete blockage of blood flow to a substantial portion of the heart.
Acute Coronary Syndrome Symptoms
Symptoms of ACS often appear suddenly and can include:
- Angina or chest discomfort described as aching, pressure, tightness, or burning
- Pain radiating to the arms, shoulders, upper abdomen, back, neck, or jaw
- Nausea or vomiting
- Indigestion
- Shortness of breath (dyspnea)
- Sudden, extensive sweating (diaphoresis)
- Dizziness, lightheadedness, or fainting
- Unusual or unexplained fatigue
- Feelings of anxiety or restlessness
Chest pain or discomfort is the most common symptom. However, signs can vary significantly based on age, sex, and preexisting medical conditions. Women, older adults, and individuals with diabetes may experience symptoms without notable chest pain.
Acute Coronary Syndrome Risk Factors
The risk factors for acute coronary syndrome overlap with those of other heart conditions. These include:
- Age
- High blood pressure
- Elevated cholesterol levels
- Smoking
- Lack of physical activity
- Poor diet
- Overweight or obesity
- Diabetes
- Family history of heart disease, stroke, or chest pain
- History of high blood pressure, preeclampsia, or diabetes during pregnancy
- COVID-19 infection