An apparatus for ablating body tissue, and particularly for creating linear lesions within a chamber of a patient's heart, is provided. The apparatus includes an elongate member having an ablation section which includes an infusion tube and a plurality of spaced electrodes. The infusion tube and electrodes are covered by a fluid permeable foam material, and the foam material is covered by a fluid impermeable covering having a plurality of holes formed in it. During use, the ablation section is placed against tissue to be ablated. This positioning step is facilitated because the ablation section of the inventive devices may be manipulated in various ways. When the ablation section is properly positioned, radio frequency energy is delivered to the electrodes while saline or other conductive fluid is delivered to the infusion tube. The fluid exits the infusion tube at the ablation section, contacts the electrodes, and carries RF energy from the electrodes through the foam, through the holes in the covering and into contact with the body tissue to form a burn in the body tissue.