Disclosed herein are various catheter and catheter systems that are useful in ablating tissue that is also subject to surface perfusion, for example blood flow across and/or through tissue. A representative embodiment of a catheter useful with the present invention includes an anemometer located on an exterior surface of the distal portion of the catheter. The anemometer is thermally isolated from the distal tip to permit the anemometer to measure the cooling effect of surface perfusion. The ablation catheter may include thermal insulation to insulate the anemometer from the distal tip. Alternatively, and/or in addition, the anemometer may be positioned proximally of the distal tip. The catheter may include one or more temperature sensors thermally coupled to the distal tip to measure the temperature of the distal tip. The distal tip may include one or more spiral grooves, or one or more holes. It is contemplated that the anemometer may be positioned within any such spiral groove or hole using a thermal insulation material, such as a non-conductive adhesive. The catheter may optionally include a contact sensor on the distal portion to assess a degree of contact between the ablation catheter and tissue being treated. Various ablation systems and methods are described herein that utilize catheters as described above.
