Introduction : With the recent Food and Drug Administration approval in February 2024 of the EVOQUE transcatheter tricuspid valve replacement (TTVR) system, and with at least 15% occurrence of conductional disorder requiring pacemaker implant, there will be an increasing need to implant leadless devices across TTVR valves. We report a case where the use of a pulmonary artery (PA) catheter facilitated navigation of the delivery catheter across a newly implanted EVOQUE valve in a severely enlarged right atrium (RA) and resulted in a successful implantation of an AVEIR VR leadless pacemaker (LP). Methods and Results : An 81-year-old woman with persistent atrioventricular block following implant of an EVOQUE TTVR system was referred for an AVEIR VR LP implant. Because of a severely enlarged RA, deflection of the delivery catheter was not sufficient to reach and engage the TTVR lumen. Using a steerable introducer, a PA catheter was advanced through the TTVR and positioned in the right PA. An extra-stiff guidewire was advanced through the PA catheter to straighten and provide stiffness. By tethering the delivery catheter to the PA catheter using a 90-degrere loop snare, the delivery catheter was advanced through the TTVR, guided by the PA catheter that functioned as a rail. Once within the right ventricle, the delivery catheter was able to successfully implant the LP onto the apical septum. Conclusion : As both TTVR and LP implants become more widely performed, the need to implant LP devices in patients with TTVR valves will only increase. Implanting an LP through a TTVR valve can be challenging when there is severe RA enlargement and delivery catheter deflection is not sufficient to reach and engage the valve lumen. While changes in delivery catheter design may eventually provide more effective deflection range, using a PA catheter as a rail for the delivery catheter can be an effective technique.