What is heart failure?

Congestive heart failure occurs when the heart is unable to maintain an adequate circulation of blood around the body because of problems with the heart’s pumping action. It does not mean the heart is about to stop. ‘Congestive’ means parts of the body collect too much fluid due to the poor circulation of blood.

How does the heart work?

The heart has four chambers with muscular walls. The upper chamber on each side is called the atrium (left and right atrium). The lower chambers are the ventricles (left and right ventricle).

Blood that is low in oxygen returns from the body and is collected in the right atrium. The blood passes into the larger, more muscular right ventricle which pumps it on to the lungs to pick up oxygen. Oxygen-rich blood from the lungs returns to the left atrium and passes into the left ventricle. The left ventricle does the most work, pumping oxygen-rich blood to the entire body.

Every minute your heart pumps four to six litres of blood around your entire body. When you are active, this amount increases dramatically.

If your heart is damaged, it may no longer be able to meet all of your body’s demands. If your body asks more than your heart can deliver, you are said to have heart failure.

Risks for heart failure

• having had any sort of heart problem before
• raised blood pressure
• raised cholesterol level
• smoking
• diabetes
• lack of physical activity
• older age 
• gender - men at greater risk than women
• family history of heart disease.

What causes heart failure?

Heart attack (also called a coronary or myocardial infarction) is the most common cause of heart failure. A heart attack occurs when coronary artery disease blocks a blood supply to the heart muscle. This can cause scarring of the heart muscle and reduce the effect of the heart's pumping action.

High blood pressure: Long term, high blood pressure can also damage heart muscle.

Cardiomyopathy is a disease of the heart muscle itself. It commonly refers to an abnormally large, baggy heart that cannot pump well enough. It can be caused by:

• some viral infections
• regularly consuming four or more alcoholic drinks per day or binge drinking - this is thought to be enough to damage the heart (if you stop altogether, there is a 50% chance the heart will recover, often completely).

For some people, even after extensive testing, a likely cause for cardiomyopathy cannot be found.

Other causes: Heart valve defects and congenital heart defects can also cause heart failure, as can excess thyroid hormone levels. Heart failure may be triggered or made worse by anaemia, infection, irregular heart beat and some drugs.

What are the symptoms?

Symptoms can vary depending on how weak your heart is. First, you may become less able to cope physically. Climbing stairs or walking may leave you tired, weak and short of breath. Shortness of breath, especially when lying down flat, is caused by a build-up of fluid in the lungs (called pulmonary oedema), which makes it harder for the lungs to transfer oxygen to the blood.

Oedema (fluid build-up) may also cause swelling of the feet, legs and abdomen and rapid weight gain due to less blood reaching the kidneys, which prevents them from disposing of salt and water as they would normally.

Other symptoms include a dry, hacking cough (most often when lying down) and loss of appetite or nausea. You may also notice a rapid pulse rate. In the elderly, unusual confusion may be the only sign.

Managing your symptoms

Managing heart failure well needs the input of your GP, who knows about your heart failure and other health issues that affect it. A heart specialist may also be involved in your care. There are also some things you can do yourself to monitor and help improve your symptoms, such as:

Weigh yourself each day
Your doctor may recommend you do this. If you put on more than 2kg over a few days, your body is retaining fluid, not fat. Your doctor will help you work out your target weight - this is your weight with no extra fluid, and is the weight at which your body and heart will work the best. Weigh yourself every morning (after you have been to the toilet, before you eat or drink anything for the day, and before you get dressed). Use digital scales, and use these on a firm surface, eg, lino or tiles.

Avoid salt (sodium)
Try not to have salt in or on your food. Salt can make you retain fluid, which can lead to breathlessness and swollen ankles.

Limit fluids
Avoid excess fluid intake, but you need not overly restrict your fluids unless your doctor advises it. Drink about the same amount each day.

Stop smoking
Smoking will make you even more breathless and will continue to damage your heart and dramatically increase your chances of a heart attack. How to quit

Limit alcohol
People with weak hearts do not cope as well with alcohol even in moderate amounts. It is best to drink only a little alcohol, and avoid binge drinking.

Rest and get a good night’s sleep
It is important not to overdo things and not to become too exhausted.

Limit stress
Try to avoid stressful situations and use relaxation techniques such as taking six deep breaths if you are becoming stressed.

Remain active
Slowly increase activity, as tolerated. Try walking gently around the house or down the road.

Lose weight if you are overweight
Losing weight takes strain off your heart.

Vaccination
Vaccination against influenza is recommended and against pneumococcal disease may be recommended.

Medications
These work best if taken regularly. If they cause you problems or side effects, talk to your doctor before stopping. Your doctor may change your pills regularly until you are on the best possible dose and combination. Many of the pills you will need to take to strengthen your heart have to start with a small dose and be built up gradually.

Coronary bypass surgery may be helpful for those who have coronary artery disease as a cause of their heart failure. Other treatments, such as pacemakers and implantable cardioverter defibrillators (ICDs) are being used to help manage heart failure in some people.

Original material provided by the Heart Foundation of New Zealand (2007, 2010). Edited by everybody, February 2011.