Heart health is something we should all be aware of. Unfortunately, it is usually something people only attend to after they have suffered a heart attack or stroke, or watched a friend or family member suffer.

Don't risk getting a second chance in life. Take action now and take care of your heart.

What is a heart attack?

Each year approximately 7,000 Irish men and women die from heart attacks due to reduced blood supply (Ischaemic Heart Disease or IHD) every year.

IHD is caused by a narrowing of the coronary arteries that supply blood to the heart and may lead to the development of chest pain or even a heart attack. Atherosclerosis is the term used to describe the narrowing of the arteries. It occurs when deposits of cholesterol and other fatty substances cause the build up of plaque on the inner lining of the arteries.


These plaques develop over many years and can affect any artery in the body. The rate at which they develop is due to a number of factors including smoking, blood pressure, cholesterol levels and genes. If the plaques are allowed to become large due to poor heart health, they will restrict the amount of blood that can be transported by the artery.


When atherosclerosis develops in the coronary arteries, the blood supply to the heart muscle is reduced so that less oxygen and nutrients reach the heart muscle, causing heart or chest pain. This chest pain is called angina pectoris.


If the atherosclerotic plaques in the lining of the coronary arteries rupture, a clot or thrombus can develop at the site of rupture, totally blocking the blood supply to that part of the heart; the result is a heart attack, also refered to as a myocardial infarction.


Also, because certain parts of the coronary arteries supply areas of the heart which regulate heartbeat (heart's natural pacemaker), a blockage affecting one of these areas can result in potentially fatal cardiac arrhythmias (abnormal heartbeats).

What are the risk factors?

There are a number of risk factors associated with the development of IHD and its consequences over which we have no control. These include a family history of heart disease, age, sex and ethnic origin. However, many of the risks associated with heart disease such as smoking, eating a high fat diet and lack of exercise are chosen by us - and it is up to us to change our bad heart health habits.

• Family history. IHD is known to run in families, indicating a genetic predisposition to developing heart disease. You are more likely to develop IHD if there is a history of IHD in first degree relatives at an early age (i.e. under 50 years in men and under 55 years in women) in your family.

If you have a strong family history of heart disease it is important that you take steps to reduce other risk factors associated with heart disease.

• Age and sex. The risk of developing IHD increases with age in both men and women. Men in the 35-44 age group have a five to six times greater risk of developing IHD than women of the same age. This difference decreases with age; a woman's risk of developing IHD increases in her mid-forties, possibly due to the onset of the menopause. Total cholesterol levels in women tend to rise after the menopause as does the risk of heart disease.

• Ethnic origin. Atherosclerosis and IHD affects all races. However, it is more common in some countries than in others. Ireland and Scotland are in the top eight countries for mortality due to IHD. Mexico, France and Japan are at the lower end of the scale. The Irish population also has a high prevalence of high blood pressure (hypertension).

 

Other risk factors that increase your risk of developing heart disease include:

• High cholesterol and/or triglyceride levels (a byproduct of fat breakdown);
• Smoking;
• Being overweight;
• Eating a high fat diet;
• Drinking alcohol excessively;
• Stress;
• Hypertension (high blood pressure);
• Diabetes.

How can I help reduce my risk of a heart attack?

By making small but significant changes in your lifestyle you can substantially reduce your risk of having a heart attack. Indeed, removing one or more of the risk factors listed below may reverse the build-up of atherosclerotic plaques.

• Reduce your cholesterol levels. Contrary to popular opinion, not all cholesterol is bad. In fact, some cholesterol is needed by the body to make cell membranes and a number of hormones. The body is capable of producing all of the cholesterol needed for these purposes so extra cholesterol from the diet is not required.

Several forms of cholesterol and triglyceride, collectively called lipids, are found in the blood stream. LDL (low density lipoprotein) cholesterol accounts for most of the cholesterol in the blood stream. LDL is the form of cholesterol that enters the lining of artery walls and causes atherosclerosis. HDL (high density lipoprotein) cholesterol carries cholesterol in a form that does not damage the artery walls; in fact it protects against the development of IHD. HDL accounts for 20-25% of the total cholesterol level. The higher the HDL level, the better.

Many studies have shown that a high level of total cholesterol in the blood is associated with increased risk of IHD. A total cholesterol level of less than 5.0 mmol/L is advised, particularly in people at high risk for IHD (i.e. those with a family history of IHD; diabetics; those with high blood pressure).

A high intake of animal fats, i.e. saturated fats, and a low intake of polyunsaturated fats increases the risk of IHD by increasing LDL cholesterol. Eating fruit and vegetables helps to reduce the risk of LDL forming plaques in the lining of artery walls. High fibre intake may increase HDL cholesterol levels.

• Quit smoking. Smoking cigarettes is a potent risk factor for heart disease. There is a three to five fold increase in the risk of IHD in men who smoke 10 cigarettes per day compared to non-smokers. There is also an increased risk of IHD in women who smoke. Cigar and pipe smokers have a smaller increased risk of IHD, possibly due to the fact that less smoke is inhaled. Once a person stops smoking, the increased risk of developing IHD drops and may return to that of non-smokers after as little as one year.

Smoking also reduces the protective HDL cholesterol levels.

• Manage your weight. In general, the risk of heart disease is greater in individuals who are more than 30 percent overweight. This is most likely due to the effect of excess weight on cholesterol levels and blood pressure than on weight alone. A close relationship between abdominal obesity and IHD has been identified in a number of studies. It is important therefore to try and maintain a normal body mass index (BMI) to reduce your risk of heart disease.

• Exercise regularly. Individuals who live a sedentary lifestyle have a higher rate of IHD than those who exercise regularly. Exactly how exercise reduces the risk of IHD is unknown but studies have shown that physical exercise is very important to protect against heart disease. Aim for 30 minutes for exercise every day, either in one spurt or broken down into smaller sessions - whichever best suits your lifestyle.

• Limit your alcohol intake. A moderate intake of alcohol can be beneficial for your heart and even reduce your risk of heart disease - and this does not only apply to red wine. However, drinking alcohol to excess can cause disease and increase your risk of heart disease, stroke, high blood pressure and cirrhosis of the liver.

The recommended alcohol limit for men is 21 units of alcohol per week and 14 units per week for women. (1 unit = ½ pint of beer, 1 glass of wine or 1 measure of sherry or spirits.)

• Reduce stress. Stress is well known to precipitate angina or even heart attacks in individuals with established IHD. Whether or not prolonged stress plays a role in the development of IHD has not been established.

• Hypertension (high blood pressure). Hypertension is caused by atherosclerosis of the arteries throughout the body. It is very likely that if a person has atherosclerosis in the general circulation, the coronary arteries will also be affected. Hypertension may cause damage to artery walls.

Hypertension is one of the most important risk factors for IHD. Studies have shown a two-fold increase in IHD risk in people with high blood pressure. It is now recommended that individuals with a blood pressure persistently above 140/90 should be treated to reduce the risk of IHD and other cardiovascular disease such as stroke.

• Diabetes. The risk of IHD is increased in people with diabetes. This is partly due to high cholesterol and low HDL. If good control of their diabetes does not correct this imbalance, drug intervention may be required.

What are the typical symptoms of a heart attack?

For each individual who suffers a heart attack, the pattern of symptoms which develop and the chances of survival are linked to the location and extent of the coronary artery blockage and the amount of heart muscle damaged.

The most common symptom of a heart attack is chest pain. This pain is usually described as "crushing," "squeezing," "pressing," "heavy" or occasionally "stabbing" or "burning."

Chest pain tends to focus either in the centre of the chest or just below the centre of the rib cage, and it may spread to the arms, abdomen, lower jaw, or neck. Unlike angina pain, chest pain associated with a heart attack usually persists. Other symptoms may include:

• Sudden weakness;
• Sweating;
• Nausea;
• Vomiting;
• Breathlessness;
• Loss of consciousness;
• Palpitations or confusion.

Written by Medpages Editorial Team
Last Editorial Review: 25/1/2010