A method for ablation in which a portion of atrial tissue around the
pulmonary veins of the heart is ablated by a first elongated ablation
component and a second elongated ablation component movable relative to
the first ablation component and having means for magnetically attracting
the first and second components toward one another. The magnetic means
draw the first and second components toward one another to compress the
atrial tissue therebetween, along the length of the first and second
components and thereby position the device for ablation of the tissue.