Cor pulmonale
Cor pulmonale is an increase in bulk of the right ventricle of the heart, generally caused by chronic diseases or malfunction of the lungs. This conditioncan lead to heart failure.
Cor pulmonale, or pulmonary heart disease, occurs in 25% of patients with chronic obstructive pulmonary disease (COPD). In fact, about 85% of patients diagnosed with cor pulmonale have COPD. Chronic and emphysema are types of COPD.High blood pressure in the blood vessels of the lungs (pulmonary hypertension) causes the enlargement of the right ventricle. In addition to COPD, cor pulmonale may also be caused by lung diseases, such as cystic fibrosis, pulmonary embolism and, pneumoconiosis. Loss of lung tissue after lung surgery or certain chest-wall disturbances can produce cor pulmonale, as can neuromusculardiseases, such as muscular dystrophy. A large pulmonary thromboembolism (blood clot) may lead to acute cor pulmonale.
Any respiratory disease or malfunction which affects the circulatory system of the lungs may lead to cor pulmonale. These circulatory changes cause the right ventricle to compensate for the extra work required to pump blood throughthe lungs. The right ventricle has thin walls and is crescent-shaped. The resulting pressure causes the right ventricle to dilate and bulge, eventually leading to its failure.
Cor pulmonale should be expected in any patient with COPD and other respiratory or neuromuscular diseases. Initial symptoms of cor pulmonale may actuallyreflect those of the underlying disease. These may include chronic coughing,wheezing, weakness, fatigue, and shortness of breath. Edema (abnormal buildupof fluid), weakness, and discomfort in the upper chest may be evident in corpulmonale.
An electrocardiograph (EKG) will show signs such as frequent premature contractions in the atria or ventricles. Chest x rays may show enlargement of the right descending pulmonary artery. This sign, along with an enlarged main pulmonary artery, indicates pulmonary artery hypertension in patients with COPD.Magnetic resonance imaging (MRI) is often the preferred method of diagnosis for cor pulmonale because it can clearly show and measure the volume of the pulmonary arteries. Other tests used to support a diagnosis of cor pulmonale may include arterial blood gas analysis (to measure the level of oxygen in theblood), pulmonary function tests (to measure how effectively the lungs are working), and hematocrit (to measure the percentage of red blood cells in the blood).
Treatment of cor pulmonale is aimed at increasing a patient's exercise tolerance and improving oxygen levels of the arterial blood. Treatment is also aimed at the underlying condition that is producing cor pulmonale. Common treatments include antibiotics for respiratory infection; anticoagulants to reduce the risk of thromboembolism; and digitalis, oxygen, and phlebotomy to reduce red blood cell count. A low-salt diet and restricted fluids are often prescribed.
The prognosis for cor pulmonale is poor, particularly because it occurs latein the process of serious disease.
Cor pulmonale is best prevented by prevention of COPD and other irreversiblediseases that lead to heart failure. Smoking cessation is critically important. Carefully following the recommended course of treatment for the underlyingdisease may help prevent cor pulmonale.