Arrhythmia is any of a group of conditions in which the electrical activity of the heart is irregular or is faster or slower than normal. Some arrhythmias are life-threatening medical emergencies that can cause cardiac arrest and sudden death. Others cause aggravating symptoms, such as an awareness of a different heart beat or palpitation, which can be annoying. Some are quite minor and can be regarded as normal. Sinus arrhythmia is the mild acceleration followed by slowing of the normal rhythm that occurs with breathing. In adults the normal resting heart rate ranges from 60 to 100 beats per minute. The normal heart beat is controlled by a small area in the upper chamber of the heart called the sinoatrial node or sinus node. The sinus node contains specialized cells that have spontaneous electrical activity that starts each normal heart beat.

Model: Scientech 2362

Model: AL-703A