New high-tech device can help atrial fibrillation sufferers

Doctors at Loyola University Medical Center in Illinois, have used a new high-tech catheter device that can improve outcomes of patients treated for atrial fibrillation, the most common irregular heartbeat.

The treatment, called catheter ablation, involves burning selected spots of tissue inside the heart with the tip of a catheter. This eliminates the sources of errant electrical signals that are triggering the atrial fibrillation.

The new device, the ThermoCool SmartTouch catheter, has just been approved by the US Food and Drug Administration. The device tells the physician the precise direction of the catheter and how hard it is pushing against the heart wall. This information is graphically displayed on a 3-D mapping and navigation system.

Loyola participated in a pivotal, multicenter clinical trial of the pressure-sensing catheter. Principal investigator at the Loyola site was David Wilber, MD, one of the nation's leading researchers in treating atrial fibrillation. Wilber is director of Loyola's Division of Cardiology and Section of Clinical Electrophysiology.

In a-fib, electrical signals that regulate the heartbeat become erratic. Instead of beating regularly, the upper chambers of the heart quiver. Not all the blood gets pumped out, so clots can form. A-fib can lead to strokes and heart failure.

A-fib symptoms include heart palpitations, dizziness, chest pain, fatigue, shortness of breath, fainting and lightheadedness.

Medications can maintain a normal heart rhythm. But when drugs don't work or cause unacceptable side effects, alternative treatments include surgery or catheter ablation. While drugs have been available for more than 30 years, ablation is a relatively new treatment.

In catheter ablation, an electrophysiologist inserts a catheter (thin flexible tube) in a groin artery and guides it through blood vessels to the heart. The tip of the catheter delivers radiofrequency energy that heats and destroys tissue that is sending out erratic electrical signals.

The challenge is to press the catheter firmly enough against the wall of the heart so that sufficient tissue is destroyed, without pushing so hard that the catheter punches a hole in the heart. This requires a very fine balance that is difficult to achieve, even for an experienced physician.

In the new device, a sensor in the tip of the catheter enables direct measurement of both the amount of contact force and the angle in which the force is being applied to the heart wall.