What causes dyspnea?

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Acute dyspnea can be caused by disturbances of the heart rhythm, failure of the left ventricle, mitral valve (a heart valve) dysfunction, or an embolus (a clump of tissue, fat, or gas) that is...

Patients who are severely anemic may develop dyspnea if they exercise vigorously

Most cases of acute dyspnea involve pulmonary (lung and breathing) disorders, cardiovascular disease, or chest trauma

Chronic dyspnea can be caused by asthma, chronic obstructive pulmonary disease (COPD), bronchitis, emphysema, inflammation of the lungs, pulmonary hypertension, tumors, or disorders of the vocal cords