Provocative Cases -> Teaching Case Reports D-AB16 - Conundrums for Device Implanters (ID 2) Abstract

D-AB16-05 - Myocardium Everywhere, But Nowhere To Pace: Leadless Pacemaker Implantation In A Patient With Ebstein’S Anomaly (ID 715)


Background: While leadless pacemaker (LPM) utilization is expanding, there is limited experience of LPM use in congenital heart disease patients.
Objective: We present a case of LPM implantation in a patient with Ebstein’s anomaly deployed under the guidance of intracardiac echocardiography (ICE) and a quadripolar catheter.
Results: A 58 year old female with a history of Ebstein's anomaly s/p bioprosthetic tricuspid valve replacement (TVR), complete heart block, permanent AF, and normal LV function had previously undergone epicardial pacemaker placement. She was referred for implantation of LPM due to high thresholds on her epicardial system (> 5 V @ 1.5 ms), and a desire to avoid repeat sternotomy and damage to the tricuspid valve. A LPM (Medtronic Micra) was maneuvered across the bioprothestic TVR into the severely enlarged RV (figure, A) under ICE guidance. Greater than 25 unsuccessful deployments were made in the atrialized RV, anatomic RV, and low RVOT due to high capture threshold or poor fixation. ICE was critical to facilitate positioning and deployment. A quadripolar catheter was also required to identify a site of adequate pace capture (figure, B). The LPM was deployed at this site and an adequate threshold (1.25V @ 0.24 ms) was recorded (figure, C). The device has demonstrated normal function with stable capture thresholds through 3 months follow-up.
Conclusion: We report the first case of LPM implantation in a patient with Ebstein’s anomaly. In patients with complex anatomy and abnormal substrate, ICE and mapping catheters can facilitate LPM placement.