Pulmonary Heart Disease |
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Because they are closely connected, disease of the lungs may have an effect on the heart. An obstruction to blood flow through the pulmonary arteries places an extra load on the right heart and it may fail. The most common causes of the are either a blood clot which forms in the veins to the right heart and into the pulmonary arteries (an embolus), or a blood clot which forms in the pulmonary arteries themselves. Drugs called anticoagulants must then be used to prevent further blood clots. If the condition is very severe, the blood clot can be removed surgically, but this is only carried out when the obstruction to blood flow becomes life-threatening. The other important disease of the lungs which affects the heart is chronic bronchitis, a disease in which the air passages in the lungs become inflamed. The effect on the heart occurs in several ways. There is actual damage to small blood vessels within the lungs, and because the lungs are ineffective at filling blood with oxygen, the body as a whole becomes deprived of oxygen. As well as causing breathlessness, this directly affects the heart: because of the lack of oxygen there is an increase in the amount of haemoglobin in the blood which causes the blood to become thicker and more difficult for the heart to pump. All these three factors can cause heart failure. Once the disease is firmly established, it cannot really be reversed and medical therapy can only play a small part. It is a good example of when prevention is more important and here, of course, smoking is a major factor. |
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