Causes and associated risk factors of heart failure.

In a minority of patients, no cause can be found, and this is called Idiopathic failure.

In the vast majority, though, heart failure is associated with an underlying problem, the commonest of which is Coronary Artery Disease (CHD). It follows then, that because Heart Failure is often the end result of CHD, all the risk factors associated with CHD will also apply to Heart Failure. The most common causes of, and associated risk factors for heart failure are:

-    Coronary Artery Disease – blockages of arteries in the heart with decreased oxygen supply to the heart muscle. These blockages are due mostly to fatty cholesterol plaques. If the plaque is eroded and a clot forms, this may totally block the artery, and cause death of heart muscle (a heart attack), which can very quickly impair the heart’s ability to pump efficiently.
-    Hypertensive heart disease – damage to the heart muscle from longstanding high blood pressure. The heart muscle may at first become thicker to try to work better, but this may cause increased stiffness and poor filling. Eventually, the heart may enlarge, and become too weak to pump effectively.
-    Valvular heart disease – heart valve problems putting strain on the heart muscle. A narrowed valve needs the heart to pump harder to get blood through the narrowing, whilst a leaking valve allows blood to flow back into the heart, causing constant overloading, and eventual enlargement.
-    Cardiomyopathy – a diseased heart muscle, often from an unknown cause, but sometimes associated with a viral infection.
-    Arrhythmia-induced heart disease – abnormal heart rhythm, leading to heart muscle damage. If the heart rate is too fast, it creates extra work for the heart. A very slow rate can prevent the heart from adequately perfusing the body, and can by itself lead to pump failure.
-    Congenital heart disease – inborn abnormalities of the heart. These are usually structural abnormalities of the chambers and valves, which therefore cannot function correctly, and rapidly cause heart failure. Some genetic defects increase the risk of certain types of heart disease, and this can in turn lead to failure.
-    Toxin-induced heart disease – exposure of the heart to various toxins such as prolonged alcohol abuse
-    Constrictive pericarditis – a disease of the sac surrounding the heart
-    Diabetes – this increases the risk of hypertension and CAD, and is often associated with obesity and raised blood cholesterol levels.
-    Kidney disorders - some are can cause high blood pressure and fluid retention.
-    Other disorders – such as hyper- or hypothyroidism, emphysema, severe anaemia can also contribute to heart failure.

Reviewed by Dr AG Hall, July 2007.