Methods for operating a selective stiffening catheter

摘要

A method for delivering RF energy to living tissue includes the steps of extending a guidewire to a tissue treatment site in a body. A controllable stiffness catheter is provided with a stiffness device and a temperature-changing device. The stiffness device is in a stiff state below a given temperature and in a soft state above the given temperature. While supplying power to the temperature-changing device, the catheter is threaded along the guidewire up to the treatment site in the flexible state of the catheter. Power is removed from the temperature-changing device to change stiffness of the stiffness device to the stiff state without straightening the catheter. The RF energy supply device is physically contacted with the treatment site and RF energy is delivered to the treatment site from the RF energy supply device.