An implantable cardioverter defibrillator (ICD) contains an algorithm that prevents unnecessary ventricular pacing and shocks. Generally, ICDs work by quickly detecting life-threatening, rapid heartbeats, or ventricular tachyarrhythmia, coming from the lower chamber of the heart. They convert the abnormal rhythm back to normal by delivering anti-tachycardia pacing pulses or an electrical shock to the heart.

But studies have shown that pacing the right ventricle when it is not necessary can cause problems, even heart failure. “We've discovered that most patients do not actually need permanent ventricular pacing,” says Andre-Michel Ballester, President of Sorin Group, (www.sorin.com) makers of the Ovatio ICD. “In fact, our studies show that less then 0.2% of patients actually required ventricular pacing. Unnecessary ventricular pacing creates a significant problem for the patient,” he adds.

The Sorin Group developed an algorithm called AAIsafeR that adapts its pacing mode to the exact need of the patient. Because it only paces when absolutely necessary, battery life is extended. “Instead of going back in the patient every 5 to 7 years, the battery can now last 7 to 10 years,” says Ballester.

The Ovatio also includes a second algorithm to save patients from unnecessary shocks that may traumatize them and reduce its life. The algorithm lets the Ovatio discriminate between supraventricular tachycardia and ventricular tachycardia down to heart rates of 100 bpm, and treat ventricular arrhythmias with anti-tachycardia pacing instead of unnecessary shocks.