When someone has a heart attack, it means there has been damage to a part of their heart muscle.
Our heart is a muscle which pumps blood around the body, delivering oxygen and other nutrients to all of our cells. It needs its own supply of oxygen and nutrients so that it can pump blood around the body which it gets from the coronary arteries, which are situated on the outside of the heart.
What happens during a heart attack?
A heart attack happens when there is a sudden loss of blood flow to a part of the heart muscle . It usually causes a sudden onset of pain or discomfort in the chest, and it may cause other symptoms.
The symptoms of a heart attack include:
Pain or discomfort in the chest that does not go away
The pain may spread to the left or right arm
Or may spread to the neck and jaw
You may feel sick or short of breath
The cause of a heart attack is nearly always coronary heart disease. This is a condition where the inside of one or more of the coronary arteries becomes narrowed because fatty deposits called atheroma have bult up within the artery walls. The fatty area of atheroma in the artery wall is called a plaque.
If a plaque cracks, a blood clot forms to try and repair the damaged artery wall. This blood clot can totally block our coronary artery, causing part of the heart muscle to be starved of blood. If this happens, the affected part of the heart muscle will begin to die, because it is not getting oxygen. This is a heart attack.
During a heart attack there is also the risk of having cardiac arrest. This is when the heart stops pumping blood and normal breathing stops.
What needs to be done if you have a heart attack?
If you have a heart attack, you need to have treatment as soon as possible. This will be to get the blood flowing to the damaged part of the heart muscle again as quickly as possible, and to limit the amount of permanent damage to your heart. Many people who have a heart attack need to have emergency treatment to unblock the coronary artery.
Either you will have a treatment called a coronary angioplasty – a procedure to re-open the blocked coronary artery.
Or you will have thrombolysis, which means giving you a ‘clot-busting’ medicine to dissolve the blood clot that is blocking the coronary artery.
If you ever suspect you are having a heart attack, call 112 immediately. Early treatment can save your life and limit the amount of damage to the heart muscle.
Medical assistance and treatment:
A suspected heart attack is treated as an emergency because of the possible damage to the heart, and the risk of death. The priorities of the medical staff are:
Take an ECG to find out whether you could be having a heart attack
Reduce your pain or discomfort
Start treatment to reduce or prevent damage to your heart, and
Resuscitate you if you go into cardiac arrest (a cardiac arrest can be triggered by a heart attack).
The ECG (electrocardiogram) is a test to find out if your symptoms are due to a heart attack. Electrodes are stuck onto your arms, legs and chest. These are connected by wires to an ECG recording machine which records the electrical activity in your heart.
If you have a low level of oxygen in your blood you will be given oxygen. To reduce your pain, you may be given morphine (intravenously through a vein) and glyceryl trinitrate under the tongue.
You may also be given Aspirin.
If the doctors decide that thrombolysis - the treatment which helps dissolve the blood clot that is blocking the coronary artery and restores the blood supply to the heart muscle - is the best treatment for you, it is given as an injection of a medicine such as recteplase or tenecteplase into the bloodstream, through a vein in the arm. This injection should be given as soon as possible after the person starts having the symptoms of a heart attack. This is partly why, if you ever think you are having a heart attack, it is vital to get medical assistance immediately, so that the blood supply to your heart muscle can be restored as quickly as possible.
Troponins are proteins that are normally found within the cells of the heart. If your heart muscle is damaged, troponins leak into your blood, where they can be detected by a blood test. They are released into your bloodstream quite slowly, so the level of troponin in your blood rises gradually over a few hours. This means that the troponins may only be detected several hours after the start of the symptoms of a heart attack. This is why the troponin test is no used as a way to decide on immediate treatment.
A Troponin test can help show if there is damage to your heart muscle.
If your troponin test is positive – that is, if you have a high level of troponins in your blood – it means that you have had a heart attack.
If the troponin test is negative several hours after your symptoms first started – that is, if you don’t have a high level of troponins in your blood – it means that your heart muscle was not damaged. This would confirm a diagnosis of unstable angina.
For some people with a suspected heart attack, a negative troponin test could also suggest that the symptoms were caused by something other than an underling heart condition. You may have more than one troponin test, especially if your first test is negative. This is because it can take some time for the troponins to be released into the bloodstream.
Cardiac Enzyme Tests are also an option as specific enzymes are produced into the bloodstream after a heart attack.