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Assessment of leadless pacemaker performance

2013; Oxford University Press; Volume: 34; Issue: suppl 1 Linguagem: Inglês

10.1093/eurheartj/eht308.1918

1522-9645

M. Bonner, Michael D. Eggen, J. Depalo, Todd Sheldon, Eric R. Williams,

ECG Monitoring and Analysis

Background: Since their invention, cardiac pacemakers have provided significant lifesaving therapy for millions of people. However, a device small enough to be placed within the heart would eliminate the pocket and the lead and thereby many of the modern pacemaker complications. We have created a 7-year VVIR pacemaker with a volume less than 1 cc that can be placed directly within the heart. In this study, we assessed the performance of the device design by comparing the pacing thresholds, R-wave amplitudes, and impedances of leadless pacemaker prototypes using three separate methods of measurement. Methods: One prototype was placed in the RV apex in each of 16 sheep via the jugular vein for a period of 6 weeks. The prototypes were constructed of a titanium main body, a distal titanium nitride coated pacing electrode with steroid, and a proximal titanium nitride ring. To allow direct measurement of the electrode potentials and currents, the electrodes were externalized through small wires that exited the prototype at the proximal end, passed through the jugular vein, and crossed the skin between the shoulder blades. The pacing thresholds, impedance and R-wave amplitudes were measured with both a breadboard of the pacemaker circuitry and a Medtronic 2290 pacing system analyzer at implant, and each week for 6 weeks. Results: The pacing thresholds at 0.2 ms and the R-wave amplitudes measured with both the analyzer and the breadboard can be seen in Figure 1. The measurements were similar between the two methods for both the threshold and R-wave measurements. In addition, both the thresholds and the R-wave amplitudes were stable over the 6 week study. Pacing Thresholds and R-wave Amplitudes Pacing Thresholds and R-wave Amplitudes Conclusions: From this study we conclude that the leadless pacemaker accurately measures pacing thresholds and R-wave amplitudes.