Catheter ablation: Comparison of SAR patterns from radiofrequency and microwave catheters

Over the last 20 years in attempts to treat high risk cardiovascular patients without subjecting them to major surgical intervention, a range of nonsurgical cathe­ter techniques have been explored. The idea was to incorporate into a catheter the ability to ablate (destroy by heating) diseased cardiac tissue without the need for surgical intervention. A number of catheter ablation techniques have been studied, but presently only radiofrequency ablation (RF) is in wide clinical use. However, due to the nature of the RF lesions (small discrete lesions concentrated near the tip of the RF catheter) the procedure has been limited to bypass tract ablations. Unfortunately the most common and life threatening arrhythmia, ventricu­lar tachyarrhythmia, requires a far larger lesiort size than RF ablation, and for that matter any presently available ablation technique, can produce.