ACUTE CORONARY SYNDROME - CAUSES, RISK FACTORS, DIAGNOSIS AND TREATMENT
Medically Reviewed by Dr. Sony Sherpa (MBBS) - July 25, 2023
Acute coronary syndrome (ACS) refers to three different forms of coronary artery disease that impact millions of people each year. The obstruction of the arteries that supply blood to the heart muscles makes it a medical emergency. It can lead to unstable angina and heart attacks.
Around 400,000 individuals die each year from acute coronary syndrome. It most frequently affects men and people with preexisting coronary heart disease. Treatment can swiftly clear blocked arteries and help your heart get the blood it needs to function normally.
Understanding Acute Coronary Syndrome
Acute coronary syndrome (ACS) comprises different coronary artery diseases that damage or destroy heart tissue. These potentially fatal disorders develop when blood flow to your heart suddenly slows or stops due to a blockage. The specific type depends on the following:
- How long the obstruction persists
- When your heart's blood flow is obstructed
- The degree of damage it causes
Types
Types of ACS include:
1. Unstable angina
This is characterized by sudden, unexpected chest pressure or pain, even at rest. It happens when stable angina worsens and is a warning indicator of a heart attack.
2. Non-ST-elevation myocardial infarction (NSTEMI)
Medical professionals can identify this type of heart attack through blood tests but not through an electrocardiogram (EKG). Instead, it indicates that your coronary arteries are partially obstructed or were briefly blocked.
3. ST-elevation myocardial infarction (STEMI)
Medical professionals can use blood tests and an ECG to identify a STEMI, a much more severe heart attack. It happens when a significant portion of your heart's blood supply is entirely restricted for an extended time.
Causes
Your heart is made up of muscles that require a steady supply of blood rich in oxygen to function effectively. The coronary arteries and their branches supply this blood.
Acute coronary syndrome is typically caused by a buildup of cholesterol and fat (plaque) on the walls of coronary arteries. Sometimes, a slow buildup of this plaque causes your arteries to stiffen and constrict (atherosclerosis). But on the other hand, this plaque can rupture or tear open quickly, resulting in acute coronary syndrome.
Blood clots form when a plaque deposit splits or ruptures. The blood clot forms over it, narrowing or obstructing blood flow to the myocardium, a section of your heart.
When the oxygen supply to the heart is inadequate, ischemia, or the lack of oxygen, destroys the heart muscle and causes unstable angina or heart attacks.
A heart attack (myocardial infarction) is the death of cells, which causes harm to muscular tissues. Even if there is no death of the heart muscles, the drop in oxygen levels still causes improper functioning. This change could be permanent or temporary.
An acute coronary syndrome is infrequently brought on by:
- Cardiovascular embolism (blockage by a blood clot, fat, air bubble, or other material)
- Spontaneous coronary artery dissection (SCAD)
- Coronary artery spasm
Symptoms
Acute coronary syndrome symptoms vary depending on the location and extent of the blockage. In addition, your age, gender, and other medical issues, such as diabetes, affect your symptoms.
Acute coronary syndrome often presents symptoms suddenly and sometimes without any warning. They can occur even while you rest. It often causes chest discomfort or pain, which can feel like:
- Burning
- Aching
- Heaviness
- Pressure
- Numbness
- Tightness
The discomfort may spread to your left shoulder, arms, back, neck, or jaw. Some people may not experience chest symptoms, though.
Other typical symptoms include:
- Nausea
- Indigestion
- Diarrhea
- Abrupt, profuse perspiration (diaphoresis)
- Breathing difficulty (dyspnea)
- Unusual or unexplained exhaustion
- Dizziness, lightheadedness, or fainting
- Feeling anxious or restless
- Racing or pounding heart (heart palpitations)
Women with acute coronary syndrome frequently do not experience chest symptoms. Unlike men, they are more likely to have:
- Nausea or vomiting
- Pain spreading to the neck, stomach, or jaw
- Breathing difficulty (dyspnea)
These symptoms are pretty serious, and you need to get medical care right away. If your symptoms continue or worsen, let your doctor know immediately. Take an aspirin, call 911, or head straight to the emergency room if you believe you are suffering a heart attack.
Who is At Risk?
The risk factors for ACS are the same as those for other types of heart disease, which include:
- Advanced age (males who are above 45 years of age or females who have reached menopause)
- Overweight or obese
- Lack of physical activity
- Cocaine use
- Smoking
- Unhealthy diet
Your health conditions and family history, such as COVID-19, diabetes, family history of heart disease, stroke, chest pain, high cholesterol levels, elevated blood pressure (hypertension), pregnancy-related high blood pressure (preeclampsia), or diabetes, puts you at a higher risk of ACS.
You may also be at increased risk if you have autoimmune or inflammatory disorders and do not get enough sleep regularly or have sleep disorders.
How To Diagnose Acute Coronary Syndrome?
An emergency doctor will conduct tests, ask about any symptoms, and review your medical history to make a quick and accurate diagnosis. Common tests consist of the following:
Electrocardiogram (ECG)
This test assesses the heart's electrical activity using electrodes attached to the skin. Impulses that are abnormal or irregular may point to the heart not getting enough oxygen. Specific electrical signal patterns may also indicate the location of a blockage.
Blood tests
If cell death damages the heart tissue, specific enzymes may be detectable in the blood. They might measure the following items:
- Cardiac enzymes
- C-reactive protein (CRP)
- Lipoproteins and triglycerides
- Fibrinogen
- Homocysteine
- Prothrombin
- Brain natriuretic peptide (BNP)
A positive result indicates a heart attack.
A primary diagnosis of acute coronary syndrome is made using the results of these two tests as well as your signs and symptoms. With the information, your doctor can decide whether your condition is an unstable angina or a heart attack.
Additional tests might be carried out to discover more about your disease, eliminate potential causes of your symptoms, or assist your doctor in determining the best course of action for you. These consist of the following:
Coronary angiogram
During this procedure, your heart's blood vessels are visible via X-ray imaging. Next, a long, thin tube (catheter) is inserted via an artery, typically in your arm or groin. This will be guided to your heart. Then, using the tube, a dye is injected into your arteries. The movement of the dye through your arteries is seen on a series of X-rays, indicating any obstructions or narrowing. Catheter-based treatments are also possible.
Myocardial perfusion imaging
This test determines how well your heart muscle receives blood. First, you will receive a tiny, safe dose of radioactive material by injection. Then, a specialized camera captures images of the substance's journey through your heart. These will show your doctor where and how much blood is flowing through the heart muscles and where blood flow is compromised.
Echocardiogram
Echocardiography creates a real-time image of your heart by using sound waves that are directed to it through a wand-like equipment. It can help determine if the heart is pumping correctly.
Computer tomography (CT) Angiogram
A CT angiogram uses sophisticated X-ray technology to provide several images of your heart that are cross-sectional 2-D slices. These scans can identify coronary arteries that are obstructed or constricted.
Stress test
A stress test demonstrates how well your heart functions during physical activity. You might occasionally be prescribed a drug to raise your heart rate instead of exercising.
This test is performed only when there are no symptoms of acute coronary syndrome or another potentially fatal cardiac problem when you are at rest. An ECG, echocardiography, or myocardial perfusion imaging may be utilized during the stress test to assess how well your heart is functioning.
Other tests
Additional tests that can assist and guide treatment and rule out other problems are:
- Calcium-score screening heart scan
- Cardiac catheterization
- Nuclear medicine imaging
Treatment Modalities
Acute coronary syndrome, being a medical emergency, prompts quick medical attention. The immediate objectives include reducing discomfort and enhancing blood flow to help restore heart function as soon as possible.
Long-term objectives include minimizing risk factors, enhancing overall heart health, and reducing the likelihood of a heart attack. The typical course of treatment includes both medications and surgical techniques.
Medications
The following medicines may be used for emergency or ongoing care (or both), depending on your diagnosis:
- Thrombolytics (clot busters) help dissolve blood clots that are obstructing arteries.
- Aspirin, prasugrel (Effient), clopidogrel (Plavix), and other antiplatelet medications work to stop blood clots from forming.
- Nitroglycerin increases blood flow by momentarily widening the blood vessels.
- Angiotensin-converting enzyme (ACE) inhibitors help the heart function more effectively. They also widen blood arteries and enhance blood flow. Benazepril (Lotensin) and lisinopril (Prinivil, Zestril) are commonly used ACE inhibitors.
- Beta-blockers aid in cardiac muscle relaxation and slow down the heart rate. As a result, they reduce blood pressure and decrease the strain on your heart. Examples include metoprolol (Toprol-XL, Lopressor) and nadolol (Corgard).
- Statins may stabilize plaque deposits, reducing the likelihood of rupture. In addition, they reduce the amount of cholesterol that is circulating through the blood. Atorvastatin (Lipitor) and simvastatin (Flolipid, Zocor) are some popular statins.
- Angiotensin receptor blockers (ARBs) help manage blood pressure. These include irbesartan (Avapro), losartan (Cozaar), and others.
Surgical procedures
Your doctor might suggest one of the following procedures to re-establish blood flow to your cardiac muscles.
Coronary bypass surgery: Here, a surgeon makes a new blood vessel that circumvents (bypasses) a blocked coronary artery by taking a segment of blood vessels from another part of your body.
Angioplasty and stenting: A long, thin tube (catheter) is inserted by your doctor into the part of your artery that is blocked or narrowed during this treatment. A wire with a deflated balloon is inserted through the catheter to reach the constricted area. When the balloon is inflated, the compressed plaque deposits against the artery walls helping to open the artery. To keep the artery open, a mesh tube (stent) is often inserted in the artery.
Lifestyle modification
Changes in lifestyle that promote heart health are crucial for preventing heart attacks. Among the recommendations are the following:
- Quit smoking: It is advisable to quit smoking if you do. If you need assistance quitting, speak to your doctor. Avoid passive smoking as well.
- Consume heart-healthy foods: Eat a diet high in fruits, vegetables, lean meats, whole grains, and low-fat dairy products.
- Check cholesterol levels: Get your blood cholesterol levels frequently checked. Avoid meat and dairy that are high in fat and cholesterol. Take any statins or other cholesterol-lowering medications your doctor has recommended as directed each day.
- Stay active. Exercise regularly and maintain your physical health. Talk to your doctor about the best exercises to start with.
- Maintain blood pressure levels: Routinely check your blood pressure, as directed by your doctor. In addition, take your blood pressure medication every day as prescribed.
- Stress management: Reduce everyday stress to lower your risk of having a heart attack. For example, consider changing your work habits and figuring out healthy methods to reduce or handle stressful situations in your life. If you need assistance managing stress, consult a medical practitioner or a mental health care specialist.
- Drink alcohol in moderation: If you do consume alcohol, do so sparingly. Blood pressure can increase if you consume more than one to two alcoholic beverages daily.
- Maintain a healthy weight: Excess weight strains your heart which can further worsen diabetes, high blood pressure, heart disease, high cholesterol, and other problems.
Other Conditions Similar To Acute Coronary Syndrome
Other medical diseases can cause non-cardiac chest pain and symptoms similar to acute coronary syndrome. Get immediate medical attention so you can receive the proper diagnosis and treatment. ACS-like conditions include:
- Aortic stenosis (narrowing of your aortic valve)
- Stress, anxiety, or depression
- Asthma
- Indigestion, esophageal spasms, or chronic acid reflux (GERD)
- Muscle or bone problems
- Blood clot in your lung (pulmonary embolism)
- Pneumonia
- Stomach issues, such as ulcers
- Rib fractures
- Inflammation of the pericardium (pericarditis)
Outlook
The prognosis for acute coronary syndrome varies depending on the particular situation, the severity, and how much heart muscle damage has occurred. However, you can increase your chances of living a long and healthy life by receiving prompt diagnosis and treatment as well as making necessary lifestyle modifications.
Follow your doctor’s advice and continue your heart-healthy behaviors. Schedule all appointments on time, and complete any tests your doctor orders. Discuss your ongoing treatment with your doctor so you know what you can do to lower your risk and prevent complications.
If you have suffered a heart attack, your doctor could advise you to enroll in a cardiac rehabilitation program to regain your strength, reduce your risk of disease, and improve your quality of life.
To search for the best Cardiology healthcare providers in Croatia, Germany, India, Malaysia, Poland, Singapore, Spain, Thailand, Turkey, the UAE, the UK and The USA, please use the Mya Care Search engine
To search for the best healthcare providers worldwide, please use the Mya Care search engine.
Sources:
- https://www.ncbi.nlm.nih.gov/books/NBK459157/
- https://www.msdmanuals.com/professional/cardiovascular-disorders/coronary-artery-disease/overview-of-acute-coronary-syndromes-acs
- https://journals.sagepub.com/doi/abs/10.1177/0885066613503294
- https://www.heart.org/en/health-topics/heart-attack/about-heart-attacks/acute-coronary-syndrome
- Makki, Nader, Theresa M. Brennan, and Saket Girotra. "Acute coronary syndrome." Journal of intensive care medicine 30.4 (2015): 186-200.
- Bergmark, Brian A., et al. "Acute coronary syndromes." The Lancet 399.10332 (2022): 1347-1358.
- Overbaugh, Kristen J. "Acute coronary syndrome." AJN The American Journal of Nursing 109.5 (2009): 42-52.
