Acute Coronary Syndrome
I was 11 years old when I first watched a man die!
On holidays, I’d sit on the small balcony of our first floor flat, reading and watching events on the street. My little friend, Hari, lived in the ground floor apartment. His grandfather worked at a bank.
That morning, grandpa waddled out of the house as usual. In one hand, the short, portly gentleman held a briefcase. A folded newspaper was tucked under his plump arm. His other hand held a cigarette.
Grandpa opened the gate. He crossed the road. All of a sudden, he stopped walking. The cigarette fell from his hand. His clenched fist gripped his shirt-front as he doubled over in distress. Passers-by rushed to his side to assist. With their help, he staggered back home.
A few minutes later, our doorbell rang. It was Hari’s uncle. He was in a panic, calling for my dad’s help. Dad was a cardiologist. He rushed downstairs.
When he returned back shortly, he delivered the shocking news. Hari’s grandpa had died. He had apparently suffered a massive heart attack.
It would be years later until I understood exactly what a heart attack was, and how acute coronary syndrome accounted for millions of preventable deaths around the world.
Maybe with better information and some common sense precautions, Hari’s grandfather might have survived his attack. This report is to provide you with this information.
It just might help save someone’s life!
Acute Coronary Syndrome
Acute Coronary Syndrome (ACS) is a blanket term given to the group of heart conditions caused by the sudden obstruction of blood flow within a coronary artery.
Acute coronary syndrome includes myocardial infarction (or heart attack) and unstable angina, both being conditions where blood flow to the heart muscle becomes blocked suddenly. To a varying extent, the heart muscle then dies or becomes irreversibly injured.
Acute coronary syndrome is a medical emergency. Immediate action to restore blood flow to the heart muscle can save lives. Whenever an acute coronary syndrome is suspected, the patient must be rushed to the nearest hospital, preferably a tertiary care institution with facilities for emergency coronary revascularization procedures.
What Are The Symptoms of Acute Coronary Syndrome?
An acute coronary syndrome must be suspected whenever a person complains of:
- chest pain or severe discomfort, especially when it radiates to the left arm or jaw and feels like burning, crushing or compressing pressure on the chest
- nausea or vomiting
- profuse sweating that drenches the clothes
- sudden breathlessness or shortness of breath
- lightheadedness, severe fatigue, or a sense of anxiety and restlessness
Any of these could be indications of an ongoing acute coronary syndrome. Prompt action in seeking medical attention can allow restoration of coronary blood flow and salvage of injured heart muscle.
Whenever acute coronary syndrome is a possibility, it is wisest to get help. Rather than try to walk or drive to hospital, it is better to call emergency services (911 in the U.S.) or get an ambulance to rush to hospital.
What Causes Acute Coronary Syndrome?
Coronary arteries are the tiny pipes that supply blood to the heart muscle itself. They provide the myocardium (heart muscle) with oxygen and nutrients to perform its life-giving work of pumping blood to the rest of the body.
There are 2 coronary arteries – the right and left coronary arteries – with multiple small branches from each supplying different portions of the heart muscle.
Acute coronary syndrome is the end-point of a long-standing series of events that begins with the accumulation of plaques in the wall of a coronary artery. Frequently this is the result of high blood levels of cholesterol, causing the excess fat to deposit on the inside of artery walls.
While the gradual but steady deposition of cholesterol on the plaque can itself cause significant narrowing of the coronary artery, what hastens this process to cause an acute coronary syndrome is an unexplained rupture of the plaque. The rough surface of the ruptured plaque then provokes blood to clot on it, suddenly occluding the affected artery completely and precipitating an acute coronary syndrome.
Risk Factors for Acute Coronary Syndrome
Factors that place someone at higher risk for acute coronary syndrome are the same ones responsible for coronary artery disease.
- High blood pressure
- Diabetes Type 2
- Elevated blood cholesterol levels
- Lack of physical exercise
- High stress levels
- Family history of heart disease
Anyone who is at higher risk of an acute coronary syndrome must be acute aware of the action to take if they experience chest pain, discomfort or any of the symptoms that may precede a heart attack. Being prepared and taking action rapidly can minimize the damage and save lives.
Most medical centers aim to get a patient’s coronary artery blood flow restored within 90 minutes of the onset of chest pain, through the use of clot busting medication or angioplasty.
How Is Acute Coronary Syndrome Diagnosed?
As soon as a patient suspected to have acute coronary syndrome arrives at hospital, an EKG (or ECG, electrocardiogram) test is done. This records the heart’s electrical activity on a strip of paper, and will indicate if there is any sign of an ongoing heart attack. (It is possible to have a heart attack even if the EKG does not show abnormalities, so it is just one of the initial screening tests.)
If the EKG is normal and chest pain is relieved with emergency treatment of acute coronary syndrome, then further tests may be deferred to a few hours later. Blood tests to measure markers of myocardial damage like the enzyme troponin will indicate whether or not a heart attack has taken place and offer an indication of the extent of muscle damage, which guides further treatment.
Other tests like an echocardiogram, nuclear scan (to evaluate blood flow to heart muscle), CT angiography, and exercise stress testing (or treadmill testing) may be necessary in acute coronary syndrome.
Emergency Treatment of Acute Coronary Syndrome
If the EKG shows signs of a heart attack, the first priority is to restore blood supply to the affected area of the heart. In hospitals and primary health care centers without advanced facilities, emergency treatment for acute coronary syndrome may take the form of using medication to dissolve any blood clot within the coronary artery and restore flow.
1. Aspirin is administered right away, preferably crushed to allow early absorption. This acts on a fresh clot to dissolve it through anti-platelet activity.
2. Clopidogrel is another platelet inhibitor which reduces the stickiness of a blood clot and encourages clot dissolution.
3. Nitroglyerine is a medication that dilates the coronary arteries in an attempt to allow some blood flow past the area of narrowing or occlusion.
4. Thrombolytics (or ‘clot busters’) are fibrinolytic drugs that act directly on a blood clot to break it up and re-establish coronary blood flow. They are most effective when used within 4 hours of the onset of chest pain, with better results coming from earlier use.
If pain persists despite these measures, indicating that coronary flow is still limited, a physician may administer morphine to relieve pain and anxiety.
In medical centers equipped with advanced facilities including a cardiac catheterization laboratory, emergency angiography with angioplasty and stenting is an option for acute coronary syndrome.
Angiography is an invasive procedure in which a tiny tube (or catheter) is threaded into an artery (femoral artery in the thigh, or radial artery at the wrist) and passed into the coronary artery where a radio-opaque dye is injected to visualize the coronaries and identify any area of blockage.
If the acute coronary syndrome is thought to be the direct consequence of an occluded coronary artery, then an angioplasty (PTCA – percutaneous trans-luminal coronary angioplasty) is performed.
A special catheter with a balloon mounted on it is threaded down the blocked coronary artery, negotiated past the clot, and the balloon inflated under pressure. Like a snowmobile blasting its way through a heavily snowed in road, the balloon catheter carves a path past the blood clot that obstructed the coronary artery.
Coronary blood flow is then instantly restored. To avoid the danger of the weakened artery wall collapsing when the balloon catheter is removed, a metal mesh (called a ‘coronary stent‘) is inserted across the previously blocked area. This keeps the artery open and lets blood continue to flow smoothly beyond it.
Some forms of acute coronary syndrome may not be suitable for angioplasty. In these cases, coronary artery bypass graft surgery (CABG) is an excellent avenue to create an alternate route of blood flow to affected heart muscle.
Prevention of Acute Coronary Syndrome
There are some steps that can avoid an acute coronary syndrome, especially in high risk groups.
1. Quit smoking. Cigarette smoking can lead to acute coronary syndrome in a variety of ways, all of which are reversed by smoking cessation.
2. Eat heart healthy food. Low saturated fat and cholesterol in diet can prevent acute coronary syndrome. A diet rich in grains, lean meat, low-fat dairy, nuts, fruits and vegetables is ideal.
3. Physical activity can reduce heart disease risk. Regular walking, household activities, and weight reduction can all protect against acute coronary syndrome.
4. Frequently monitor blood sugar and cholesterol levels, taking appropriate measures to keep them within normal range. It can avoid heart attacks and angina.
5. Maintain normal blood pressure through natural measures or medication to help prevent acute coronary syndrome.
6. Reduce stress, practice yoga, meditation and lead a balanced lifestyle. All are contributory to avoiding heart disease.
7. Drink in moderation. You can postpone the onset of coronary artery disease and prevent acute coronary syndrome.
With some simple measures and an awareness about what to do in case of an acute coronary syndrome, it is possible to avoid the condition or minimize the damage that may result from it.
In other sections of this site, we will discuss other elements of this process in greater detail.