SAN DIEGO -- Doctors at the University of California, San Diego San Diego Medical Center are using a robotic arm to help treat patients with an irregular heartbeat, it was announced Monday.

The system is operated by a three-dimensional joystick, similar to a computer game, to position a catheter that transmits radio waves that helps "short circuit" abnormal electrical activity in the heart.

"The robotic system aids in the precision of the ablation treatment for atrial fibrillation to within one to two millimeters of accuracy," said Dr. Gregory Feld, director of UCSD's cardiac electrophysiology program.

"Combined with software that creates a three-dimensional map of the heart, this new technology offers greater stability, reduces exposure to x-rays and shortens the overall procedure time -- good news for patients and doctors."

More than 2.2 million Americans suffer from atrial fibrillation, a condition in which the upper chambers of the heart beat in a rapid, irregular manner, out of sync with the lower chambers.

It is most often treated by introducing a thin tube, or catheter, through a blood vessel in the leg and up into the heart. Electrodes on the catheter then record the heart's electrical signals to locate the abnormality.