Larry Chinitz1, Philippe Ritter2, Surinder Kaur Khelae3, Saverio Iacopino4, Christophe Garweg5, Maria Grazia-Bongiorni6, Petr Neuzil7, Jens Brock Johansen8, Lluis Mont9, Efrain Gonzalez10, Venkata Sagi11, Gabor Z Duray12, Nicolas Clementy13, Todd Sheldon14, Vincent Splett14, Kurt Stromberg14, Nicole Wood14, Clemens Steinwender15. 1. NYU Langone Medical Center, New York, New York. Electronic address: larry.chinitz@nyumc.org. 2. Hopital Du Haut Leveque, Pessac, France. 3. Institut Jantung Negara, Selangor, Malaysia. 4. GVM Care and Research, Lamezia Terma, Italy. 5. UZ Leuven, Diegem, Belgium. 6. University Hospital of Pisa, Pisa, Italy. 7. Na Homolce Hospital, Prague, Czech Republic. 8. Odense University Hospital, Odense, Denmark. 9. Hospital Clinic, Universitat de Barcelona, Barcelona, Spain. 10. Baptist Hospital of Miami, Miami, Florida. 11. Southern Heart Group, Jacksonville, Florida. 12. Military Hospital-State Health Center, Budapest, Hungary. 13. CHU de Tours, Chambray-les-Tours, France. 14. Medtronic, plc, Mounds View, Minnesota. 15. Department of Cardiology, Kepler University Hospital, Linz, Austria; Paracelsus Medical University Salzburg, Salzburg, Austria.
Abstract
BACKGROUND: Micra is a leadless pacemaker that is implanted in the right ventricle and provides rate response via a 3-axis accelerometer (ACC). Custom software was developed to detect atrial contraction using the ACC enabling atrioventricular (AV) synchronous pacing. OBJECTIVE: The purpose of this study was to sense atrial contractions from the Micra ACC signal and provide AV synchronous pacing. METHODS: The Micra Accelerometer Sensor Sub-Study (MASS) and MASS2 early feasibility studies showed intracardiac accelerations related to atrial contraction can be measured via ACC in the Micra leadless pacemaker. The Micra Atrial TRacking Using A Ventricular AccELerometer (MARVEL) study was a prospective multicenter study designed to characterize the closed-loop performance of an AV synchronous algorithm downloaded into previously implanted Micra devices. Atrioventricular synchrony (AVS) was measured during 30 minutes of rest and during VVI pacing. AVS was defined as a P wave visible on surface ECG followed by a ventricular event <300 ms. RESULTS: A total of 64 patients completed the MARVEL study procedure at 12 centers in 9 countries. Patients were implanted with a Micra for a median of 6.0 months (range 0-41.4). High-degree AV block was present in 33 patients, whereas 31 had predominantly intrinsic conduction during the study. Average AVS during AV algorithm pacing was 87.0% (95% confidence interval 81.8%-90.9%), 80.0% in high-degree block patients and 94.4% in patients with intrinsic conduction. AVS was significantly greater (P <.001) during AV algorithm pacing compared to VVI in high-degree block patients, whereas AVS was maintained in patients with intrinsic conduction. CONCLUSION: Accelerometer-based atrial sensing is feasible and significantly improves AVS in patients with AV block and a single-chamber leadless pacemaker implanted in the right ventricle.
BACKGROUND:Micra is a leadless pacemaker that is implanted in the right ventricle and provides rate response via a 3-axis accelerometer (ACC). Custom software was developed to detect atrial contraction using the ACC enabling atrioventricular (AV) synchronous pacing. OBJECTIVE: The purpose of this study was to sense atrial contractions from the Micra ACC signal and provide AV synchronous pacing. METHODS: The Micra Accelerometer Sensor Sub-Study (MASS) and MASS2 early feasibility studies showed intracardiac accelerations related to atrial contraction can be measured via ACC in the Micra leadless pacemaker. The Micra Atrial TRacking Using A Ventricular AccELerometer (MARVEL) study was a prospective multicenter study designed to characterize the closed-loop performance of an AV synchronous algorithm downloaded into previously implanted Micra devices. Atrioventricular synchrony (AVS) was measured during 30 minutes of rest and during VVI pacing. AVS was defined as a P wave visible on surface ECG followed by a ventricular event <300 ms. RESULTS: A total of 64 patients completed the MARVEL study procedure at 12 centers in 9 countries. Patients were implanted with a Micra for a median of 6.0 months (range 0-41.4). High-degree AV block was present in 33 patients, whereas 31 had predominantly intrinsic conduction during the study. Average AVS during AV algorithm pacing was 87.0% (95% confidence interval 81.8%-90.9%), 80.0% in high-degree block patients and 94.4% in patients with intrinsic conduction. AVS was significantly greater (P <.001) during AV algorithm pacing compared to VVI in high-degree block patients, whereas AVS was maintained in patients with intrinsic conduction. CONCLUSION: Accelerometer-based atrial sensing is feasible and significantly improves AVS in patients with AV block and a single-chamber leadless pacemaker implanted in the right ventricle.
Authors: Clemens Steinwender; Hermann Blessberger; Daniel Kiblböck; Karim Saleh; Jürgen Kammler Journal: Herzschrittmacherther Elektrophysiol Date: 2018-11-19
Authors: Zak Loring; Rebecca North; Anne S Hellkamp; Brett D Atwater; Camille G Frazier-Mills; Kevin P Jackson; Sean D Pokorney; Gervasio A Lamas; Jonathan P Piccini Journal: Pacing Clin Electrophysiol Date: 2020-11-05 Impact factor: 1.976