Each normal heartbeat starts in an area of the heart known as the sinus node which is located in the upper right chamber of the heart (right atrium). The sinus node contains specialized cells that send an organized electrical signal through the heart resulting in a perfectly timed, rhythmic heartbeat. In patients with atrial fibrillation, however, the atria fibrillate (or “quiver”) due to chaotic electrical signals that circulate throughout both atria. This typically results in a fast and irregular heartbeat. While some patients have no symptoms, others may experience shortness of breath, lightheadedness and fatigue. Depending on your specific medical history and symptoms, your physician may recommend a cardioversion to return your heart to a normal rhythm.
What is an electrical cardioversion?
Cardioversion is a brief procedure where an electrical shock is delivered to the heart to convert an abnormal heart rhythm back to a normal rhythm. Most elective or “non-emergency” cardioversions are performed to treat atrial fibrillation or atrial flutter, benign heart rhythm disturbances originating in the upper chambers (atria) of the heart. Cardioversion is used in emergency situations to correct a rapid abnormal rhythm associated with faintness, low blood pressure, chest pain, difficulty breathing, or loss of consciousness.
Electrical cardioversion or DC cardioversion
Is a procedure whereby a synchronized electrical shock is delivered through the chest wall to the heart through special electrodes or paddles that are applied to the skin of the chest and back . The goal of the cardioversion is to interrupt the abnormal electrical circuit in the heart and to restore a normal heart beat. The shock causes all the heart cells to contract simultaneously, thereby interrupting and terminating the abnormal electrical rhythm (typically fibrillation of the atria) without damaging the heart. This split second interruption of the abnormal beat allows the heart’s electrical system to regain control and restore a normal heartbeat.
An electrical cardioversion is performed in a hospital setting such as an emergency room, intensive care unit, recovery room, special procedure room or Electrophysiology Laboratory. A cardiologist, a nurse and/or an anesthesiologist are present to monitor your breathing, blood pressure and heart rhythm. Special cardioversion pads are placed on your chest and back (or alternatively, both pads can be placed on the front of the chest). The pads are connected to an external defibrillator by a cable. The defibrillator allows the medical team to continuously monitor your heart rhythm and to deliver the electrical shock to restore your heart’s rhythm back to normal.