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Updated: Aug 11, 2026

A New Single Chamber Implantable Defibrillator with Atrial Sensing: A Practical Demonstration of Sensing and Ease of Implantation
Published on: February 28, 2012
[Atypical sinus node dysfunction. Usefulness of implantable Holter. A case report]
J Martí Almor1, J Delclòs Urgell, J Bruguera Cortada
1Unidad de Arritmias, Servicio de Cardiología, Hospital del Mar, Barcelona, Spain.
Abstract:
We present an 84 year-old female patient with repeated syncopes/presyncopes in the last nine years. All diagnosis tests were negative, including ECG, 24-hour Holter, tilt table test and EP study. Therefore, a subcutaneous insertable loop recorder was implanted (Reveal). The recording of three episodes showed the association of presyncope with the onset of atrial fibrilation and, in two syncopes, with an atrial pause between AF episodes. Probably an abnormal prolonged sinus node recovery time (more than 6 s) allowed AF to restart before the sinus rhythm.
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