Description: Generally, shortness of breath (dyspnea) that can occur at rest, with exercise (exertional dyspnea), while lying down (orthopnea), or suddenly in the middle of the night while asleep (paroxysmal nocturnal dyspnea, or PND).
Some causes related to cardiovascular disease: Dyspnea can be an important sign of cardiac problems including cardiac ischemia and cardiomyopathy.
Some causes related to other disorders: Pulmonary disorders, such as asthma and emphysema, are a common cause of breathing problems.
Significance: Anyone with dyspnea needs to have a full medical examination in order to determine the underlying cause.

