First aid for heart failure
Heart failure is a disorder in which the heart loses its ability to pump blood efficiently throughout the body. Heart failure often results from conditions which increase the workload of the heart. The heart may have coped with this increased workload for many years before heart failure occurs.
Heart failure may affect the left, right, or both sides of the heart. If the left half of the heart fails (left ventricular failure), fluid will build up in the lungs due to congestion of the veins of the lungs. If the right half of the heart fails (right ventricular failure), general vein pressure will increase and fluid will accumulate in the body, especially the tissues of the legs and abdominal organs.
As both sides of the heart work in series, once one side starts to fail it is not long before the other side is affected.
Heart failure can be caused by many different diseases and conditions and can occur either as an acute, sudden effect or as a chronic, long-standing condition. Causes of heart failure can include:
- Ischemic heart disease. A blood clot in one of the coronary arteries can cause injury and irreversible damage to the heart muscle;
- Hypertension (high blood pressure). A patient is often considered to be hyperten- sive if the systolic blood pressure is equal to or greater than 140 mmHg or diastolic is over 90 mmHg;
- Diseases of the heart valves resulting in narrowed or leaking valves;
- Cardiomyopathy. A disease in which the heart muscle becomes inflamed and reduces efficiency. Cardiomyopathy occurs in three major types: dilated cardiomyopathy involving enlargement of one or more of the heart’s chambers; hypertrophic cardiomyopathy which involves thickening of the heart’s muscle and restrictive cardiomyopathy which results in the heart muscle becoming more rigid;
- Congenital heart diseases. Congenital heart disease can describe a number of dif- ferent abnormalities of the heart’s structure and function caused by abnormal or disor- dered heart development before birth;
- Endocrine (hormone) disorders;
- Severe anaemia (deficiency of red blood cells, which can lead to a lack of oxygen- carrying ability and ischaemia).
Left ventricular failure (LVF)
The most common causes of left heart failure are damage to the muscular pump of the left ventricle caused by a heart attack, and diseases of the mitral valve and aortic valve.
The left side of the heart cannot pump all of the blood it receives to the systemic circulation so blood backs up in the pulmonary circulation. These pulmonary vessels become congested and the alveoli gradually fill with fluid, impairing the exchange of gases in the lungs.
Right ventricular failure (RVF)
Right ventricular failure may be secondary to LVF or it may occur independently. When the right side of the heart fails, it cannot effectively pump blood to the pulmonary arteries and lungs, resulting in increased pressure on the venous system. This leads to blood pooling in the veins and oedema developing in tissues and organs. Up to seven litres of water may be retained before oedema becomes visibly obvious.
Congestive heart failure (CHF)
Congestive heart failure is the inability of the heart to pump a sufficient amount of blood throughout the body, or requiring elevated filling pressures in order to pump effectively.
Signs and symptoms of heart failure
The signs and symptoms of heart failure can be difficult to differentiate from other causes of breathlessness, but a thorough physical examination and medical history can assist is identifying heart failure. When conducting an assessment of a patient with heart failure ensure to examine:
- the respiratory rate and work of breathing;
- presence of peripheral oedema (patients may sometimes state that their shoes or slippers have felt tighter over the last few days or weeks
- difficulty sleeping or laying flat (patients may state that they have increased the number of pillows they sleep with or have started sleeping in an armchair);
- the presence of any cough, frothy white or pink sputum (yellow, green or brown sputum usually indicates a chest infection);