Sinus Arrhythmia
Sinus arrhythmia refers to a normal variation in the heart rhythm caused by breathing. It is not a true arrhythmia, in the sense that it is not a truly abnormal heart rhythm. In fact, in most cases sinus arrhythmia is actually a sign of a healthy, well functioning heart.
Heart Attacks in Children
The technical term for a heart attack is a myocardial infarction. Fortunately heart attacks in children are exceedingly rare. In adults, a myocardial infarction is typically caused by inadequate blood flow to the heart muscle. This is usually a result of atherosclerosis, or plaque build-up in the coronary arteries, the arteries that feed the heart muscle with blood. Plaque build-up results from risk factors such as high cholesterol, high blood pressure, diabetes, smoking, obesity, and genetic factors. When plaque build-up become severe, the artery becomes partially blocked. If a partially blocked artery becomes completely occluded by a blood clot, a myocardial infarction or heart attack results.
Cyanosis
Cyanosis refers to a blue discoloration of the skin. Hemoglobin is the molecule found in red blood cells which is responsible for carrying oxygen. When oxygen is bound to hemoglobin, blood has a red color. When oxygen is released from hemoglobin, blood turns a blue color. Cyanosis most commonly is caused by a lower than normal oxygen saturation of hemoglobin in the blood.
Cardioversion
An arrhythmia refers to any abnormal heart rhythm. Arrhythmias are typically divided into slow heart rhythms (bradycardia) and fast heart rhythms (tachycardia). Treatment for most forms of symptomatic bradycardia involves speeding up the heart rate. On the other hand, treatment for most forms of tachycardia involves slowing the heart rate, or preferably converting it back to a normal heart rhythm. This process is known as cardioversion.
Atrial Flutter
Atrial flutter refers to an arrhythmia, or an abnormal heart rhythm that involves an electrical circuit formed in the atrium, the upper two chambers of the heart. Normal electrical conduction in the heart starts with the generation of electricity in the sinus node in the upper portion of the right atrium. Electricity moves from the sinus node through the atrium. From there, it is transmitted to the AV node to the ventricles. As electricity passes to the ventricles, the heart muscle contracts.