Acute Coronary Syndrome - Know It All!


All you need to know about Acute Coronary Syndrome.

Know your ailment well, so you can manage it better!!

What is Acute Coronary Syndrome?

Acute Coronary Syndrome 

What are the types of Acute coronary syndrome?

Acute coronary syndrome (ACS) applies to a number of clinical manifestations ranging from those with myocardial infarction with ST-segment elevation (STEMI) to those found in myocardial infarction with non-ST segment elevation (NSTEMI) or unstable angina. It is almost always linked to atherosclerotic plaque rupture and partial or complete infarct-related artery thrombosis.

The picture below shows an algorithm for the triage of chest pain patients.

Acute Coronary Syndrome 

What are the types of Acute coronary syndrome?

Acute coronary syndromes are classified by doctors based on:

  • The existence of blood substances (cardiac markers) that are produced by the weakened heart:
  • The Symptoms
  • Data from electrocardiography ( ECG)

The definition is important because, based on the actual acute coronary syndrome, therapies vary. Unstable angina and two forms of heart disease are part of the classification.

Unstable Angina:

Unstable angina is a new symptom of healthy angina or a transition from it. Angina can develop more often, at rest, feel more serious more quickly, or last longer. While oral drugs can also ease this angina, it is unpredictable and can lead to a heart attack. More intensive medical rehabilitation or a surgery is normally needed. Unstable angina is an acute coronary condition that is a medical emergency that should be treated.

Heart attack: Non-ST segment elevation myocardial infarction (NSTEMI):

This heart attack, or MI, does not cause electrocardiogram ( ECG) changes. Chemical markers in the blood, however, suggest that the heart muscle has sustained injury. The blockage can be partial or reversible in NSTEMI, and the magnitude of the damage is thus comparatively limited.

Heart attack: ST segment elevation myocardial infarction (STEMI):

This heart attack, or MI, does not cause electrocardiogram ( ECG) changes. Chemical markers in the blood, however, suggest that the heart muscle has sustained injury. The blockage can be partial or reversible in NSTEMI, and the magnitude of the damage is thus comparatively limited.


  • The muscle of the heart requires a steady flow of blood rich in oxygen. This blood is supplied through the coronary arteries, which branch from the aorta shortly after it exits the nucleus. An acute coronary syndrome develops when the blood flow to an area of the heart muscle (myocardium) is significantly reduced or cut off by a sudden blockage of a coronary artery. It is also ischemia, the absence of blood flow to some tissue. Heart tissue dies if the flow is significantly lowered or shut off for longer than a few minutes. A cardiac attack is the destruction of heart tissue leading to ischemia, also known as myocardial infarction ( MI).
  • The most frequent cause of a damaged coronary artery is a blood clot. Usually, an accumulation of cholesterol and other fatty materials in the artery wall (atheroma) already partly narrows the artery. An atheroma can burst or tear, which releases substances that render stickier platelets, facilitating the formation of clots. The blood clot dissolves on its own, usually within a day or so, in around two-thirds of people. At this point, though, any cardiac injury has usually developed.
  • Rarely, as a clot develops in the heart itself, falls free, and lodges in a coronary artery, a heart attack occurs. A spasm of a coronary artery that prevents blood supply is another rare source. Drugs such as cocaine can trigger spasms. The trigger is unclear occasionally.

What are  the signs and symptoms?

The signs and symptoms of acute coronary syndrome usually begin abruptly. They include:

  • Chest pain (angina) or discomfort, often described as aching, pressure, tightness or burning
  • Pain spreading from the chest to the shoulders, arms, upper abdomen, back, neck or jaw
  • Nausea or vomiting
  • Indigestion
  • Shortness of breath (dyspnea)
  • Sudden, heavy sweating (diaphoresis)
  • Lightheadedness, dizziness or fainting
  • Unusual or unexplained fatigue
  • Feeling restless or apprehensive

The most prominent symptom is chest pain or nausea. However, depending on your age, sex and other medical conditions, signs and symptoms can differ greatly. If you’re a woman, an older adult or have diabetes, you’re most likely to have signs and symptoms without chest pressure or nausea.

Acute Coronary Syndrome 

The main cause of ACS is atherosclerosis, with most cases resulting from the disruption of a previously non-severe lesion. Documented grievances and symptoms by patients with ACS include the following:

  • Palpitations
  • Pain that is generally defined in the precordium as pressure, pressing, or a burning sensation that may radiate to the throat, shoulder, jaw, back, upper abdomen, or either arm
  • Dyspnea with exertion that resolves with pain or rest
  • Sympathetic discharge diaphoresis
  • Vagal activation nausea
  • Decreased tolerance for exercise

Physical effects will differ between standard and any of the following:

  • Hypotension: Suggests ventricular instability due to myocardial ischemia, myocardial infarction ( MI) or acute valve disease.
  • Hypertension: Can induce angina precipitation or indicate increased levels of catecholamine due to anxiety or exogenous sympathomimetic stimulation

With diaphoresis:

  • Pulmonary oedema and other symptoms of weakness of the left heart
  • Vascular Extracardiac Disease
  • Venous jugular distention
  • Cool, clammy skin and diaphoresis in cardiogenic shock patients
  • A third sound of the heart (S3), and also a fourth sound of the heart (S4)
  • A systolic murmur connected to complex left ventricular outflow tract obstruction
  • Rales (suggested left ventricular dysfunction or mitral regurgitation) on pulmonary examination
Acute Coronary Syndrome 

What are the risk factors of Acute Coronary Syndrome?

Acute coronary syndromes, just like heart failure and stroke, are much more likely in people who have certain risk factors. These include:

  • Smoking
  • High blood pressure
  • High blood cholesterol
  • Diabetes
  • Physical inactivity
  • Being overweight or obese
  • A family history of chest pain, heart disease or stroke

What are the complications of Acute Coronary Syndrome?

  • Ischemia: Pulmonary oedema
  • Myocardial infarction: Rupture of the papillary muscle, left ventricular free wall, and ventricular septum

How is Acute Coronary Syndrome Diagnosed?

If you have signs or symptoms consistent with the acute coronary syndrome, multiple scans will possibly be ordered by an emergency department doctor. When the doctor is telling you questions about your conditions or medical records, certain testing should be performed.

Required tests:

  • Electrocardiogram (ECG). Electrodes attached to your skin to measure the electrical activity in your heart. Abnormal or irregular impulses can mean your heart is not working properly due to a lack of oxygen to the heart. Certain patterns in electrical signals may show the general location of a blockage. The test may be repeated several times.
  • Blood tests. Certain enzymes may be detected in the blood if cell death has resulted in damage to heart tissue. A positive result indicates a heart attack.

A primary diagnosis of the acute coronary syndrome is made using the details from these two studies, as well as your signs and symptoms. In order to decide if the illness should be identified as a heart attack or dysfunctional angina, the doctor can use the details.

In order to understand more about your illness, to rule out potential sources of complications, or to help your doctor personalise your diagnosis and treatment, other tests can be performed.

  • Coronary angiogram. This procedure uses X-ray imaging to see the heart’s blood vessels. A long, tiny tube (catheter) is threaded through an artery, usually in your arm or groin, to the arteries in your heart. A dye flows through the tube into your arteries. A series of X-rays show how the dye moves through your arteries, revealing any blockages or narrowing. The catheter may also be used for treatments.
  • Echocardiogram. An echocardiogram uses sound waves, directed at your heart from a wand-like device, to produce a live image of your heart. An echocardiogram can help determine whether the heart is pumping correctly.
  • Myocardial perfusion imaging. This test shows how well blood flows through your heart muscle. A tiny, safe amount of radioactive substance is injected into your blood. A specialized camera takes images of the substance’s path through your heart. They show your doctor whether enough blood is flowing through heart muscles and where blood flow is reduced.
  • Computerized tomography (CT) angiogram. A CT angiogram uses a specialized X-ray technology that can produce multiple images — cross-sectional 2-D slices — of your heart. These images can detect narrowed or blocked coronary arteries.
  • Stress test. A stress test reveals how well your heart works when you exercise. In some cases, you may receive a medication to increase your heart rate rather than exercising. This test is done only when there are no signs of acute coronary syndrome or another life-threatening heart condition when you are at rest. During the stress test, an ECG, echocardiogram or myocardial perfusion imaging may be used to see how well your heart works.
Acute Coronary Syndrome 
Acute Coronary Syndrome 

What is the treatment for Acute Coronary syndrome?

The immediate targets of acute coronary syndrome therapy are:

  • Relieve anxiety and suffering
  • Enhancing the supply of blood
  • Restore the work of the heart as efficiently and as best as possible

Long-term aims of therapy include optimising improved heart function, mitigating risk factors, and reducing the risk of a heart attack. To achieve these targets, a variety of medications and surgical procedures may be used.


Depending on your diagnosis, medications for emergency or ongoing care (or both) may include the following:

  • Thrombolytics (clot busters) help dissolve a blood clot that’s blocking an artery.
  • Nitroglycerin improves blood flow by temporarily widening blood vessels.
  • Antiplatelet drugs help prevent blood clots from forming and include aspirin, clopidogrel, prasugrel and others.
  • Beta-blockers help relax your heart muscle and slow your heart rate. They decrease the demand on your heart and lower blood pressure. Examples include metoprolol and nadolol.
  • Angiotensin-converting enzyme (ACE) inhibitors widen blood vessels and improve blood flow, allowing the heart to work better. They include lisinopril, benazepril and others.
  • Angiotensin receptor blockers (ARBs) help control blood pressure and include irbesartan, losartan and several others.
  • Statins lower the amount of cholesterol moving in the blood and may stabilize plaque deposits, making them less likely to rupture. Statins include atorvastatin, simvastatin and several others.
Acute Coronary Syndrome 

Surgery and Other Procedures:

Your doctor may recommend one of these procedures to restore blood flow to your heart muscles:

  • Angioplasty and stenting. In this procedure, your doctor inserts a long, tiny tube (catheter) into the blocked or narrowed part of your artery. A wire with a deflated balloon is passed through the catheter to the narrowed area. The balloon is then inflated, opening the artery by compressing the plaque deposits against your artery walls. A mesh tube (stent) is usually left in the artery to help keep the artery open.
  • Coronary bypass surgery. With this procedure, a surgeon takes a piece of the blood vessel (graft) from another part of your body and creates a new route for blood that goes around (bypasses) a blocked coronary artery.

How to prevent the disease:

Doctors consider taking one baby aspirin, one half of an adult aspirin, or one entire adult aspirin every day for those who have suffered a heart attack. Since aspirin protects platelets from developing clots, it lowers by 15 to 30 per cent the risk of death and the risk of a second heart attack. Clopidogrel can be taken by people with an aspirin allergy instead.

Doctors have also usually recommended taking low-dose aspirin regularly to avoid heart problems and strokes for those who have not suffered a heart attack but who are over 50 years of age and have 2 or more risk factors. Aspirin, though, may also cause problems such as gastrointestinal bleeding, and new research shows that in people who have not experienced a heart attack, these complications can counterbalance the potential advantage of aspirin. Doctors assist individuals to weigh their individual risk and benefit.

A beta-blocker (such as metoprolol) is typically recommended by physicians and these medications decrease the chance of mortality by around 25 per cent. The more extreme a heart attack is, the higher the advantage of beta-blockers. However, the side effects (such as wheezing, nausea, erectile dysfunction, and cold limbs) can not be ensured by certain individuals, and not all gains.

The risk of death after a heart attack would be decreased by taking lipid-lowering medications. Lipid-lowering drugs may help people at high risk (especially obese individuals with diabetes) who have not yet had a heart attack or stroke.

Since a heart attack, angiotensin-converting enzyme (ACE) antagonists are frequently recommended, such as captopril, enalapril, perindopril, trandolapril, lisinopril, and ramipril. These medicines help prevent death and the development of heart disease, particularly in individuals who have suffered a significant heart attack or who have heart failure.

In their lifestyle, people should also make adjustments. They should eat a diet that is low in fat and increase the amount of exercise they get. People who have high blood pressure or diabetes should try to keep those disorders under control. People who smoke should quit.


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