Systems and methods for improving response of implantable leads to magnetic fields during medical procedures such as magnetic resonance imaging (MRI) are described. In various embodiments, the lead includes an inner conductor that is helically shaped and radially surrounded, at least in part, by one or more high-voltage conductors. The high-voltage conductor can be mechanically and/or electrically coupled, via a coupler, to the shocking coil. The pitch of the inner and/or outer conductor can be varied (e.g., continuously or at certain points) along the length of the lead. In some embodiments, the filar thickness, the pitch, and the mean coil diameter of the inner coil, the high voltage conductor coil, and the shock coil can be configured such that these coils have a desired inductance value when subjected to externally applied electromagnetic energy at radio frequencies commonly generated by MRI scanners (e.g., 40 MHz to 300 MHz).