THERAPEUTIC PROCEDURES << BACK Radiofrequency Ablation with Electrocardiographic Pace-Mapping Radiofrequency ablation is a nonsurgical treatment for some abnormal heart rhythms. It is most often use rapid, uneven heart rhythms called supraventricular tachyarrhythmias. Radiofrequency ablation is done by a physician using a catheter, a tiny, slender tube, with an electrode at its tip, guided to the area of the heart muscle. The catheter is placed at the exact site inside the heart where cells give off the electrical signals that stimulate the abnormal heart rhythm. Then a mild, painless burst of radiofrequency energy is transmitted to the cells, destroying them in a very small area. This treatment stops the heart muscle from conducting the electrical impulses that caused the rapid heartbeats. Electrocardiographic imaging (ECGI) is a noninvasive way to provide high resolution, three-dimensional images of cardiac electrical activity to help guide radiofrequency ablation. ECGI uses CT images of the heart and body surface geometry. This information is used to create high-resolution maps of the body and its internal systems. Surface data is collected and recorded while the patient is fitted with a multi-electrode vest connected to a multi-channel mapping system. Patented computer algorithms generate ECGI images in various useful formats for the physician to clearly see the area causing the abnormal heart rhythms.