Atrial fibrillation is the most common heart rhythm problem. More than one million Americans suffer from this disorder that causes the heart to beat up to 140 to 160 times per minute, compared to a normal rhythm of 60 to 100 beats per minute. Because the heart beats so rapidly it cannot fully contract, placing the body at risk for the development of blood clots, and stroke.
Attacks can last anywhere from a few minutes periodically or for weeks or even years on end.
The defibrillator is implanted in much the same way as a pacemaker. The patient is sedated but awake and is given a local anesthetic at the site of insertion. The defibrillator sends a small shock to the heart's upper chambers when atrial fibrillation occurs, correcting the rhythm abnormality before clots can form. However, drugs aren't always effective. University Hospitals of Cleveland is one of only three U.S. sites studying the implantable atrial defibrillator.