Steerable electrophysiology catheters for use in mapping and/or ablation
of accessory pathways in myocardial tissue of the heart wall and methods of use
thereof are disclosed. The catheter comprises a catheter body and handle, the catheter
body having a proximal section and a distal section and manipulators that enable
the deflection of a distal segment of the distal tip section with respect to the
independently formed curvature of a proximal segment of the distal tip section
through a bending or knuckle motion of an intermediate segment between the proximal
and distal segments. A wide angular range of deflection within a very small curve
or bend radius in the intermediate segment is obtained. At least one distal tip
electrode is preferably confined to the distal segment which can have a straight
axis extending distally from the intermediate segment. The curvature of the proximal
segment and the bending angle of the intermediate segment are independently selectable.
The axial alignment of the distal segment with respect to the nominal axis of the
proximal shaft section of the catheter body can be varied between substantially
axially aligned (0 curvature) in an abrupt knuckle bend through a range of
about -;90 to about +180 within a bending radius of between about 2.0
mm and 7.0 mm and preferably less than 5.0 mm. The proximal segment curve can be
independently formed in a about +180 through about +270 with respect
to the axis of the proximal shaft section to provide an optimum angular orientation
of the distal electrode(s). The distal segment can comprise a highly flexible elongated
distal segment body and electrode(s) that conform with the shape and curvature
of the heart wall.
