A guidewire for use in a medical procedure includes an elongate guide member dimensioned for insertion within a body vessel of a subject. The guide member defines a longitudinal axis and has trailing and leading end segments. The leading end segment has a reduced cross-sectional dimension relative to a cross-sectional dimension of the trailing end segment. The leading end segment includes a first core element comprising a first material and a second core element comprising a second material different from the first material and being forward of the first core element. The first material of the first core element has greater rigidity than the rigidity of the second material of the second core element, to thereby facilitate advancement of, and application of torque to, the leading end segment while minimizing deformation. The first material of the first core element may comprise a nickel-cobalt-chromium alloy or, alternatively, stainless steel. The second material of the second core element comprises a nickel-titanium or an alloy thereof.