An interventional catheter specifically designed for use in an MRI guided intervention comprising: - a transmission line (stl) comprising a first proximal segment and a second distal segment, each of the segments having two electrically parallel leads, wherein the leads of the first segment are electrically connected in series to the leads of the second segment by a reactive coupling unit (103, CU), in particular a transformer coupling unit, the transmission line having its distal end near the catheter's tip, - two pacing electrodes (E1, E2) at the catheter's tip, the first pacing electrode being connected to the first lead of the distal segment and the second pacing electrode being connected to the second lead of the distal segment; - a rectifier diode inserted in the first lead close to the catheter's tip and operable for supplying to the pacing electrodes a DC cardiac pacing pulse which is modulated on an RF carrier and transmitted over the transmission line; a low pass filter inserted between the rectifier diode and the pacing electrodes, the low pass filter comprising a capacitor interconnecting the first lead and the second lead of the distal segment, - an active MR tracking circuit formed by a tunable resonant circuit electrically connected on the proximal side of the rectifier diode between the rectifier diode and the transmission line, wherein the tunable resonant circuit comprises a tracking coil, and a varactor, the varactor being capacitively isolated from the tracking coil and operable for tuning the tracking coil to an MR resonance frequency, the varactor and the tracking coil being connected in parallel to one another between the first lead and the second lead, the varactor being positioned on the proximal side of the tracking coil, and - highly-resistive wires for supplying a DC tuning voltage to the varactor in an RF-safe way. - a transmission line (stl) comprising a first proximal segment and a second distal segment, each of the segments having two electrically parallel leads, wherein the leads of the first segment are electrically connected in series to the leads of the second segment by a reactive coupling unit (103, CU), in particular a transformer coupling unit, the transmission line having its distal end near the catheter's tip, - two pacing electrodes (E1, E2) at the catheter's tip, the first pacing electrode being connected to the first lead of the distal segment and the second pacing electrode being connected to the second lead of the distal segment; - a rectifier diode inserted in the first lead close to the catheter's tip and operable for supplying to the pacing electrodes a DC cardiac pacing pulse which is modulated on an RF carrier and transmitted over the transmission line; a low pass filter inserted between the rectifier diode and the pacing electrodes, the low pass filter comprising a capacitor interconnecting the first lead and the second lead of the distal segment, - an active MR tracking circuit formed by a tunable resonant circuit electrically connected on the proximal side of the rectifier diode between the rectifier diode and the transmission line, wherein the tunable resonant circuit comprises a tracking coil, and a varactor, the varactor being capacitively isolated from the tracking coil and operable for tuning the tracking coil to an MR resonance frequency, the varactor and the tracking coil being connected in parallel to one another between the first lead and the second lead, the varactor being positioned on the proximal side of the tracking coil, and - highly-resistive wires for supplying a DC tuning voltage to the varactor in an RF-safe way.