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Pulmonary heart disease (New Latin pulmōnāle, ''of the lungs''), also known as ''Cor pulmonale'' (Latin cor, ''heart'' + of the lungs) is the enlargement and failure of the right ventricle of the heart as a response to increased vascular resistance or high blood pressure in the lungs (pulmonary hypertension). Chronic pulmonary heart disease usually results in right ventricular hypertrophy (RVH), whereas acute pulmonary heart disease usually results in dilatation. Hypertrophy is an adaptive response to a long-term increase in pressure. Individual muscle cells grow larger (in thickness) and change to drive the increased contractile force required to move the blood against greater resistance. Dilatation is a stretching (in length) of the ventricle in response to acute increased pressure, such as when caused by a pulmonary embolism or ARDS (acute respiratory distress syndrome). To be classified as pulmonary heart disease, the cause must originate in the pulmonary circulation system. Two major causes are vascular changes as a result of tissue damage (e.g. disease, hypoxic injury, chemical agents, etc.), and chronic hypoxic pulmonary vasoconstriction. If left untreated, then death may result. RVH due to a systemic defect is not classified as pulmonary heart disease. The heart and lungs are intricately related. Whenever the heart is affected by disease, the lungs will follow and vice versa. Pulmonary heart disease is by definition a condition when the lungs cause the heart to fail.〔(American Medical Network - Pulmonary Heart Disease ), Retrieved on 2010-01-25.〕 The heart has two pumping chambers. The left ventricle pumps blood throughout the body. The right ventricle pumps blood to the lungs where it is oxygenated and returned to the left heart for distribution. In normal circumstances, the right heart pumps blood into the lungs without any resistance. The lungs usually have minimal pressure, and the right heart easily pumps blood through to them.〔(Pulmonary Heart Disease Information ), Retrieved on 2010-01-25.〕 However with certain lung diseases chronically present, like emphysema and chronic bronchitis, each of which is found in the pathology of chronic obstructive pulmonary disease (COPD), and also pulmonary hypertension, the blood vessels of the lungs are significantly reduced in number (due to lung tissue destruction) and/or chronically constricted (due to poor alveolar ventilation in the case of COPD). The right ventricle is no longer able to push blood into the lungs effectively, and the chronic overload eventually causes it to fail. ==Signs and symptoms== The symptoms of pulmonary heart disease depend on the stage of the disorder. In the early stages, one may have no symptoms but as pulmonary heart disease progresses, most individuals will develop the symptoms like: *Shortness of breath which occurs on exertion but when severe can occur at rest *Wheezing *Chronic wet cough *Swelling of the abdomen with fluid (ascites) *Swelling of the ankles and feet (pedal edema) *Enlargement or prominent neck and facial veins *Raised jugular venous pressure (JVP) *Enlargement of the liver *Bluish discoloration of the skin (cyanosis) *Presence of abnormal heart sounds *possible bi-phasic atrial response shown on an EKG due to hypertrophy 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Pulmonary heart disease」の詳細全文を読む スポンサード リンク
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