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Updated: Jun 5, 2025

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Published on: July 20, 2022
Utility of the Novel Auto + A3 Threshold Function in Maintaining Atrioventricular Synchrony
Ryo Ohinata1, Naoya Inoue1,2, Shuji Morikawa1,2
1Department of Cardiology, Chutoen General Medical Center, Kakegawa, Shizuoka, Japan.
Introduction:
The VDD-leadless pacemaker aims to maintain high atrioventricular (AV) synchrony, but proper sensing setup is crucial.
Methods And Results:
This case was an elderly woman with an AV block who received a dual-chamber pacemaker. Due to ventricular pacing failure, a Micra AV2 was implanted. However, postimplantation, high sinus rate, and frequent premature ventricular contractions were noted. Therefore, the auto + A3 threshold function was used in the atrial-sensing setup. A few days later, the MAM test confirmed good AV synchrony.
Conclusion:
The auto + A3 threshold function equipped in the Micra AV2 may offer to maintain high AV synchrony.
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