A heart attack, also called a myocardial infarction or MI, can be fatal, but treatment has improved dramatically over the years.
What Causes Heart Attack?
The heart muscle requires a constant supply of oxygen-rich blood to nourish it. The coronary arteries are the major blood vessels that supply the heart with blood.
Coronary heart disease (CHD) is the leading cause of heart attacks. CHD is a condition in which the coronary arteries get clogged up with deposits of cholesterol and other substances. These deposits are called plaques.
A heart attack occurs when the flow of blood to any part of the heart muscle is blocked, most often by a build-up of fat, cholesterol and other substances, which form a plaque in any of the coronary arteries. Fatty matter, calcium, proteins and inflammatory cells build up within the arteries to form plaques of different sizes. The plaque deposits are hard on the outside and soft and mushy on the inside.
When the plaque is hard, the outer shell cracks (plaque rupture), platelets (disc-shaped particles in the blood that aid clotting) come to the area, and blood clots form around the plaque. If a blood clot totally blocks the artery, the heart muscle becomes deprived of oxygen. Within a short time, death of heart muscle cells occurs, causing damage. This is a heart attack.
The following factors are associated with increased risk of a heart attack:
Age: Heart attacks are more likely when a man is over 45, and when a woman is over 55.
Angina: This causes chest pain due to lack of oxygen or blood supply to the heart.
High cholesterol levels: These can increase the chance of blood clots in the arteries.
Diabetes: This can increase heart attack risk.
Diet: For example, consuming large quantities of saturated fats can increase the likelihood of a heart attack.
Genetics: A person can inherit a higher risk of heart attack.
Heart surgery: This can lead to a heart attack later on.
Hypertension: High blood pressure can put unnecessary strain on the heart.
Obesity: Being significantly overweight can put pressure on the heart.
Previous heart attack.
Smoking: Smokers are at much higher risk than non-smokers.
HIV: People who are HIV-positive have a 50 percent higher risk.
Work stress: Those who are shift workers or have stressful jobs can face a higher heart attack risk.
Lack of physical activity: An inactive lifestyle contributes to high blood cholesterol levels and obesity. People who get regular aerobic exercise have better cardiovascular fitness, which decreases their overall risk of heart attack. Exercise is also beneficial in lowering high blood pressure.
Illegal drug use: Using stimulant drugs, such as cocaine or amphetamines, can trigger a spasm of your coronary arteries that can cause a heart attack.
A history of preeclampsia. This condition causes high blood pressure during pregnancy and increases the lifetime risk of heart disease.
A history of an autoimmune condition, such as rheumatoid arthritis or lupus: Conditions such as rheumatoid arthritis, lupus and other autoimmune conditions can increase your risk of having a heart attack.
Often, when it occurs, a heart attack is caused by a combination of factors, rather than a single one.
The best way of preventing a heart attack is to live a healthy lifestyle. Measures for healthy living include the following:
maintaining blood cholesterol at optimum levels
keeping blood pressure at a safe level
maintaining a healthy body weight
getting plenty of good quality sleep
keeping diabetes under control
keeping alcohol intake down
getting plenty of exercise
avoiding stress where possible
learning how to manage stress
Getting regular medical checkups. Some of the major risk factors for heart attack such as high blood cholesterol, high blood pressure and diabetes cause no symptoms early on. Your doctor can perform tests to check for these conditions and help you manage them, if necessary.
Eating a heart-healthy diet. Saturated fat, trans fats and cholesterol in your diet can narrow arteries to your heart, and too much salt can raise blood pressure. Eat a heart-healthy diet that includes lean proteins, such as fish and beans, plenty of fruits and vegetables and whole grains.
It may be helpful for people to learn more about the warning signs of a heart attack, as well.
Signs and Symptoms
There are clear symptoms of a heart attack that require immediate medical attention.
A feeling of pressure, tightness, pain, squeezing, or aching in the chest or arms that spreads to the neck, jaw or back can be a sign that a person is having a heart attack.
The following are other possible signs and symptoms of a heart attack occurring:
crushing chest pain
shortness of breath called dyspnoea
face seeming gray in colour
a feeling of terror that life is ending
feeling awful, generally
feeling clammy and sweaty
Changing position does not alleviate the pain of a heart attack. The pain a person feels is normally constant, although it may sometimes come and go.
As heart attacks can be fatal, it is vital to recognize the warning signs that an attack is occurring.
While the symptoms listed above are all linked to heart attacks, there are four warning signs listed by the American Heart Association (AHA) as being crucial signs of an attack. These include:
discomfort, pressure, squeezing, or fullness in the chest that lasts several minutes or resolves then returns
pain or discomfort in the arms, neck, back, stomach, or jaw
sudden shortness of breath
Other signs can include a cold sweat, a sick or nauseous feeling, or being lightheaded.
When a person has these symptoms, the emergency services should be called immediately.
Some people have a heart attack without having any symptoms and this could be referred to as a "silent" myocardial infarction (MI). A silent MI can occur in anyone, but it is more common among people with diabetes.
Complications are often related to the damage done to your heart during an attack. Damage can lead to:
Abnormal heart rhythms (arrhythmias). Electrical "short circuits" can develop, resulting in abnormal heart rhythms, some of which can be serious, even fatal.
Heart failure. An attack may damage so much heart tissue that the remaining heart muscle can't adequately pump blood out of your heart. Heart failure may be temporary, or it can be a chronic condition resulting from extensive and permanent damage to your heart.
Heart rupture. Areas of heart muscle weakened by a heart attack can rupture, leaving a hole in part of the heart. This rupture is often fatal.
Valve problems. Heart valves damaged during a heart attack may develop severe leakage problems.
These complications can occur quickly after a heart attack and are a leading cause of death. Many people die suddenly from a complication of a heart attack before reaching hospital, or within the first month after a heart attack.
Any doctor, nurse, or healthcare professional will send someone straight to hospital if they suspect they may be having a heart attack. Once there, several tests may be done, including:
ECG or electrocardiograph
cardiac enzyme tests
The best time to treat a heart attack is within one to two hours of the first onset of symptoms. Waiting longer increases the damage to your heart and reduces your chance of survival.
The quicker someone is treated when having a heart attack, the greater the chances of success. These days, most heart attacks can be dealt with effectively.
However, it is crucial to remember that a person's survival depends largely on how quickly they reach the hospital.
Most people will need several kinds of medications or treatments after a heart attack. The aim of these measures is to prevent future heart attacks occurring. They may include:
aspirin and other antiplatelets
ACE (angiotensin converting enzyme) inhibitors
CABG or coronary artery bypass graft
What to do if you see someone having a heart attack:
If you encounter someone who is unconscious, first call for emergency medical help. Then begin CPR to keep blood flowing. Push hard and fast on the person's chest in a fairly rapid rhythm (about 100 to 120 compressions a minute). It's not necessary to check the person's airway or deliver rescue breaths unless you've been trained in CPR. (To learn more about performing CPR, click here)
Recovering from a heart attack can be a gradual process. The time it takes to recover from a heart attack will depend on the amount of damage to the heart muscle and other factors, such as a person's age.
A person's recovery may involve:
Resuming physical activity: it is vital that a recovering heart attack patient stays active. However, a specialist should design any exercise programme for them.
Returning to work: the appropriate time for someone to go back to work depends on various factors, including the severity of the heart attack and the type of job they do. It is vital not to rush back to work. Some people are well enough to return to work after two weeks. Other people may take several months to recover.
A period of depression: many people who have had a heart attack experience depression not long afterward. Those who feel depressed or anxious should tell their doctors.
Driving again: experts advise that a person refrains from driving for at least 4 weeks after a heart attack.
Erectile dysfunction: approximately one-third of men have problems getting or sustaining an erection after a heart attack. It is important that men with erectile dysfunction talk to their doctors, as medication can restore function in most cases.
Experts say that sexual activity does not raise a person's risk of having another heart attack.
Sex after a heart attack
Some people worry about having sex after a heart attack, but most people can safely return to sexual activity after recovering from a heart attack. When you can resume sexual activity will depend on your physical comfort, psychological readiness and previous sexual activity. Ask your doctor when it's safe to resume sexual activity.
Some heart medications may affect sexual function. If you're having problems with sexual dysfunction, talk to your doctor.
The outlook often depends on:
Age: serious complications are more likely as you get older
The severity of the heart attack: how much of the heart's muscle has been damaged during the attack
How long it took before a person received treatment: treatment for a heart attack should begin as soon as possible
The amount of damage to the heart muscle depends on the size of the area supplied by the blocked artery and the time between injury and treatment.
Healing of the heart muscle begins soon after a heart attack and takes about eight weeks. Just like a skin wound, the heart's wound heals and a scar will form in the damaged area. But, the new scar tissue does not contract. So, the heart's pumping ability is lessened after a heart attack. The amount of lost pumping ability depends on the size and location of the scar.
How Are Future Heart Attacks Prevented?
The goal after your heart attack is to keep your heart healthy and reduce your risks of having another heart attack. Your best bet to ward off future attacks are to take your medications, change your lifestyle, and see you doctor for regular heart checkups.