Bronchial asthma and cardiac asthma
Bronchial asthma is another name for asthma. The term ‘bronchial’ is occasionally used to differentiate it from what is sometimes called ‘cardiac’ asthma, which is not a form of asthma, but actually breathing difficulties caused by heart failure. Although the two conditions have similar symptoms, including shortness of breath and wheezing (a whistling sound in the chest), they have quite different causes and so treatment differs.
‘Cardiac asthma’ is really a set of symptoms caused by congestion and fluid build up in the lungs (pulmonary oedema), resulting from heart failure. It is more common in older people.
In ‘cardiac asthma’, the reduced pumping efficiency of the left side of the heart leads to build up of fluid in the lungs. This fluid build up can cause breathlessness and wheezing.
Symptoms of cardiac asthma
Cardiac asthma has some symptoms that can mimic those of bronchial asthma. The main symptoms and signs of ‘cardiac asthma’ are:
- shortness of breath;
- dry cough;
- rapid and shallow breathing;
- frothy or watery sputum;
- coughing up blood-tinged mucus;
- symptoms worse at night.
The pattern of shortness of breath can help doctors determine which condition you have. People with bronchial asthma tend to experience shortness of breath early in the morning, whereas people with heart failure and cardiac asthma often find they wake up suddenly breathless a few hours after going to bed, and have to sit upright to catch their breath.
This is because in people with heart failure, lying down for prolonged periods will cause fluid to accumulate in the lungs leading to shortness of breath. If they sit up in bed for a while the symptoms may subside.
Both asthma and heart failure can make people short of breath when they exert themselves.
In (bronchial) asthma, symptoms are usually brought on by vigorous exercise and tend to be worse after the exercise than during it.
On the other hand, ‘cardiac asthma’ tends to happen during less vigorous exertion — someone with heart failure can find themselves short of breath and wheezing while climbing stairs, or in severe cases, while getting dressed.
People with heart failure also often have problems with swollen ankles that worsen during the course of the day. They may also feel very tired, put on weight and have to urinate frequently.
‘Cardiac asthma’ can be a life-threatening condition, and you should consult your doctor if you think you have symptoms of ‘cardiac asthma’.
What’s the treatment for ‘cardiac asthma’?
The treatment for ‘cardiac asthma’ is essentially to treat the cause of the underlying heart problem, whether it be heart failure or a leaky heart valve, and the excess fluid in the lungs. Medicines may be needed to reduce blood pressure, including diuretics which help reduce fluid retention. If the heart failure can be treated effectively, this may in turn relieve the respiratory symptoms known as ‘cardiac asthma’.
People who awaken suddenly in the night with symptoms of ‘cardiac asthma’ may improve the situation by sitting upright for half an hour. There is no evidence that using bronchodilators (medicines that are routinely used in bronchial asthma) will help, and they may even worsen the situation.
Bronchial asthma, or asthma as it’s normally referred to, is caused by inflammation of the airways, which results in them narrowing.
Symptoms of bronchial asthma
The symptoms of bronchial asthma include:
- a feeling of tightness in the chest;
- difficulty in breathing or shortness of breath;
- wheezing or whistling in the chest; and
- coughing – persistent cough is a common symptom; it may be worse at night.
For most people with bronchial asthma, the pattern is they feel well most of the time and can breathe normally, but have periodic attacks (flare-ups) of narrowing of their airways and wheezing. However people with severe asthma may alternate between chronic (long-term) shortness of breath and episodes in which they feel even more breathless than usual.
Risk factors for asthma
Risk factors for developing bronchial asthma include being exposed early in life to indoor allergens, such as dust mites, moulds and cockroaches, and having a family history of asthma or allergy. Exposure to tobacco smoke before birth or during early childhood also increases the risk of developing bronchial asthma.
Triggers for bronchial asthma
Bronchial asthma attacks can be triggered (precipitated or aggravated) by various factors, including:
- viral infections of the upper respiratory tract, such as colds and flu;
- cold dry air;
- exercise (exercise-induced asthma);
- allergens (substances that trigger an allergic reaction) such as pollen, house dust mites, cockroaches and mould;
- cigarette smoke, bushfire smoke and other air pollutants;
- thunderstorms and
- strong emotions, singing, laughing and stress.
In some people, asthma can be triggered by exposure to aspirin or other non-steroidal anti-inflammatory drugs. Other medicines, such as beta-blockers, can also trigger bronchial asthma.
Some people develop asthma due to an allergy that they develop to certain chemicals in the workplace (this is called ‘occupational asthma’) in which case exposure to the chemical triggers an asthma attack.
Treatment of bronchial asthma
Although there is currently no cure for bronchial asthma, it can be managed with medication and lifestyle changes. Medications are taken by mouth or inhaled and help to open up your airways. Work with your doctor to develop a written asthma action plan and learn to manage flare-ups and control your asthma symptoms.
Last Reviewed: 25/11/2020
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