Microwave antenna design for myocardial tissue ablation applications

Summary form only given. Transcatheter ablation, a technology for electrically annihilating aberrant heart tissue, has been developed to cure certain forms of life-threatening cardiac arrhythmia. Originally entirely surgical procedures were used to remove the aberrant tissue but more recently three techniques have been developed for ablating cardiac tissues through electronically induced heating. These are: (1) the high energy DC-induced current method, (2) the radiofrequency (RF) energy method, and (3) the microwave probe radiator method. With all three techniques a flexible catheter probe is inserted, via a small incision made in an arm or leg, into the body through a vein and into the heart. The two former methods produce ablative heat through current flow from an electrode at the tip of the catheter to an electrode pad placed on the surface of the skin. The latter method produces heat exclusively through microwave radiation from the catheter probe. Presently the RF probe is most widely used because it avoids painful side-effects associated with high energy DC-induced current. As yet, only the high frequency radiator method has not been developed to the point that it can be used in humans. In the present paper some ofthe advantages, design challenges and research on the myocardial transcatheter microwave probe are discussed.