Texas Cardiac Arrhythmia Institute at St. David's Medical Center became the first in the US to make use of the long-awaited NaviStar RMT ThermoCool Catheter to treat abnormal heart rhythms, or arrhythmias. The novel technology has received FDA approval on 27 Feb, 2009. NaviStar RMT ThermoCool Catheter for radiofrequency (RF) ablation is used with the NIOBE Magnetic Navigation System, which helps steer a catheter remotely and guide ablation to targeted areas that require treatment. NaviStar RMT ThermoCool Catheter uses heat to destroy abnormal heart muscle that causes atrial fibrillation. The novel technology is sprays cooled saline and physicians believe it is safer and more effective than previous catheters and poses fewer risks for complications. The temperature at the tip of the catheter reached 65 degrees Celsius previously, which could cause blood clots on the heart tissue. This thermoCool catheter maintains a temperature of no more than 42 degrees Celsius while ablation energy is being delivered to the heart tissue.