Some nebulae create their own light, which sometimes has a fluorescent appearance, while others only reflect the light from nearby stars. Nebulae are often seen around dying stars, and it's thought they may be a natural process that occurs when a star is nearing the end of its life. Nebulae resemble thin clouds that have less atoms per cubic inch than a cloud of smoke.
Cardiomyopathy is a group of diseases that affect the heart muscle. Early on there may be few or no symptoms. Some people may have shortness of breath, feel tired, or have swelling of the legs due to heart failure. An irregular heart beat may occur as well as fainting.
Damage to the heart that hurts its ability to pump blood is called congestive heart failure (CHF). Sleep disorders can be both a cause and an effect of CHF. The low oxygen levels and high blood pressure related to obstructive sleep apnea (OSA) can cause the kind of damage that leads to CHF. The heart muscle is unable to handle the stress caused by the OSA.