Acute Coronary Syndrome (ACS) is a group of serious heart conditions caused by a sudden reduction or blockage of blood flow to the heart muscle. It occurs when the heart does not receive enough oxygen-rich blood through the coronary arteries. ACS is most commonly associated with the rupture or erosion of a fatty plaque inside a coronary artery, followed by the formation of a blood clot (thrombus). The clot can partially or completely block blood flow to the heart. Acute coronary syndrome is a medical emergency because prolonged reduction in blood flow can damage or permanently destroy heart muscle. ACS generally includes:
Unstable angina– reduced blood flow to the heart without evidence of heart muscle death.
Non-ST-elevation myocardial infarction (NSTEMI)– a heart attack caused by partial or temporary blockage of a coronary artery.
ST-elevation myocardial infarction (STEMI)– a serious heart attack, usually caused by complete or prolonged blockage of a coronary artery.
Symptoms can develop suddenly and may vary from person to person. The most common symptom is chest discomfort, but some people—particularly older adults, women, and people with diabetes—may experience less typical symptoms. Common symptoms include:
Chest pain, pressure, tightness, squeezing, heaviness, or discomfort
Pain or discomfort spreading to one or both arms
Pain or discomfort in the shoulder, jaw, neck, back, or upper abdomen
Shortness of breath (dyspnea)
Nausea or vomiting
Indigestion or a feeling similar to severe heartburn
Sudden or excessive sweating (diaphoresis)
Rapid or irregular heartbeat or palpitations
Dizziness or lightheadedness
Unusual or extreme fatigue
Weakness
Restlessness, anxiety, or a feeling that something is seriously wrong
The most common underlying cause of ACS is coronary artery disease (CAD). Over time, fatty substances such as cholesterol can accumulate within the walls of the coronary arteries and form atherosclerotic plaques. These plaques can narrow the arteries and reduce blood flow. ACS can occur when a plaque becomes unstable and ruptures or erodes, causing a blood clot to form around it. The clot can rapidly narrow or completely block the artery, reducing oxygen supply to the heart muscle. Less commonly, ACS may result from other mechanisms, such as:
Severe spasm of a coronary artery
Spontaneous coronary artery dissection (SCAD)
Severe anemia or very low oxygen levels
Extremely high blood pressure or other conditions that significantly increase the heart’s oxygen demand
Rarely, other causes of sudden coronary blood-flow obstruction
ACS requires prompt medical evaluation. Doctors may use several tests to determine whether a person is experiencing a heart attack or another form of ACS.
An echocardiogram uses ultrasound to create images of the heart. It can show how well the heart is pumping and whether particular areas of the heart muscle are moving abnormally.
Treatment depends on the type of ACS, the severity of the blockage, the patient’s overall health, and the results of diagnostic tests. Because ACS can rapidly become life-threatening, treatment is usually started urgently. Treatment may include:
A procedure called percutaneous coronary intervention (PCI) may be performed to reopen a blocked coronary artery. During PCI, a thin catheter is guided to the affected artery. A balloon may be inflated to widen the narrowed area, and a stent may be placed to help keep the artery open.
In some patients with severe or extensive coronary artery disease, coronary artery bypass grafting (CABG) may be recommended. During CABG, a surgeon creates a new route for blood to flow around blocked or severely narrowed coronary arteries.
After an episode of ACS, lifestyle changes and long-term medical treatment are important to reduce the risk of another heart attack or cardiovascular event. Recommended measures may include:
Stop smoking and avoid tobacco products
Maintain a healthy body weight
Follow a heart-healthy diet
Exercise regularly as advised by a healthcare professional
Control blood pressure
Manage cholesterol levels
Keep diabetes under good control
Take prescribed medicines regularly
Limit excessive alcohol consumption
Manage stress
Attend cardiac rehabilitation when recommended
Keep regular follow-up appointments with a healthcare professional
Not exactly. ACS is an umbrella term that includes unstable angina and two major types of heart attack: NSTEMI and STEMI. Therefore, every heart attack is a form of ACS, but not every case of ACS is a heart attack.
Yes. Suspected ACS requires immediate medical evaluation because a blocked coronary artery can cause permanent heart muscle damage or become life-threatening.
Yes. Some people may have mild or atypical symptoms, and some may have little or no obvious chest pain. Symptoms such as unexplained shortness of breath, sweating, nausea, dizziness, or unusual fatigue can sometimes occur.
The most common cause is atherosclerotic coronary artery disease, in which fatty plaques develop inside coronary arteries. Rupture or erosion of a plaque can trigger a blood clot that suddenly reduces blood flow.
The risk can often be reduced by controlling cardiovascular risk factors. Not smoking, maintaining a healthy weight, eating a heart-healthy diet, exercising regularly, and controlling blood pressure, cholesterol, and diabetes are important preventive measures.
Yes. Medicines can significantly reduce cardiovascular risk but cannot completely eliminate the possibility of ACS. Any new or worsening symptoms suggestive of a heart attack require urgent medical evaluation.
Medical Disclaimer: Information provided on MyMediLand is for general educational purposes and should not replace examination, diagnosis, or treatment by a qualified healthcare professional. If you suspect a heart attack or acute coronary syndrome, seek emergency medical care immediately.
