What Are Supraventricular Cardiac Arrhythmias?

At rest, the average human heart beats roughly 75 times and pumps roughly 5 liters of blood per minute. The heartbeat is strictly controlled by a critical electrical node, but sometimes this node malfunctions. The resulting irregular heartbeat is called an arrhythmia.

• Heart

The Heart and Arrhythmias

• The human heart has four chambers and is made up mostly of cardiac muscle tissue. Arrhythmias are irregular heartbeat rhythms, and supraventricular arrhythmias occur in the two atrial chambers, which are located above the ventricles (hence the name). Arrhythmias are the result of problems with the heart's sinoatrial node, which regulates the heartbeat.

Prevalence

• According to the American Heart Association, approximately 2.2 million Americans live with abnormal heart rates associated with atrial arrhythmias. Heart attacks and aging increase the risk of a serious arrhythmia.

Symptoms

• If your heartbeat is too slow (bradycardia), you will feel tired and weak. If your heartbeat is too fast (tachycardia), you will feel dizzy and have a strong, rapid pulse.

Mortality

• Most cases of arrhythmia are not serious, but if left uncontrolled, arrhythmias can lead to fibrillation. This condition is most certainly life threatening, because the heart begins to beat faintly and uncontrollably. Brain death can occur within minutes of the onset of fibrillation.

Treatment

• Medications such as beta blockers and calcium channel blockers or artificial pacemakers are the standard treatments for supraventricular arrhythmias.