Innovative implantation of a leadless pacemaker in a 19 kg paediatric patient via the right internal jugular vein

A 7-year old, 19 kg, woman with mitochondrial DNA deletion syndrome with progressive infra-Hisian block presented for a pacemaker placement. Her comorbidities included thrombocytopenia, sideroblastic anaemia, immunosuppression, chronic kidney disease needing transplant, failure to thrive, gastric tube, and 10-year life expectancy. Discussion occurred regarding risks and benefits of ventricular only pacing. Her right internal jugular vein (RIJ) diameter was 12 mm. Given her comorbidities/future infection risk, parents opted for leadless pacing instead of epicardial/transvenous pacing. The Micra deployment sheath was placed via RIJ access after serial dilation by 2-Fr steps (6–27-Fr delivery sheath). Due to small right ventricular size, anteroseptal position was obtained by minimal contrast and fluoroscopy guidance. One deployment was made with threshold of 1 V@0.24 ms, R-wave 5 mV, and impedance 480 Ohms (Figure 1 ). Prior to full reversal from heparin, the patient developed a moderate pericardial effusion. This was drained with tube removal 2 days later without further effusion. The RIJ access site healed well (closed with figure-of-8 stitch). Next-day interrogation demonstrated threshold of 0.5 V@0.24 ms, R-wave 6.2 mV, impedance 530 Ohms with similar values at 4-month follow-up. Placement of a paediatric leadless pacemaker via the RIJ in a 19-kg patient is possible but represents the lower size limit with difficult to obtain mid-septal position. The full-length version of this report can be viewed at: https://www.escardio.org/Education/E-Learning/Clinical-cases/Electrophysiology.