Prospective evaluation of the quality and long- term stability of atrial signals in non-thoracotomy defibrillation electrodes : Comparison of four different Endocardial electrograms

• Published in: Journal of interventional cardiac electrophysiology 1998-12, Vol.2 (4), p.351-355
• Main Authors: WOLPERT, C, JUNG, W, SPEHL, S, SCHUMACHER, B, OMRAN, H, ESMAILZADEH, B, LÜDERITZ, B
• Format: Article
• Language: English
• Subjects: Algorithms; Arrhythmias, Cardiac - physiopathology; Arrhythmias, Cardiac - therapy; Biological and medical sciences; Defibrillators, Implantable - standards; Diseases of the cardiovascular system; Electrophysiology - methods; Endocardium; Follow-Up Studies; Heart Atria - physiopathology; Heart Rate; Humans; Medical sciences; Ostomy; Prospective Studies; Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects); Thoracotomy
• ISSN: 1383-875X; 1572-8595
• DOI: 10.1023/A:1009708604125

Documentation of atrial signals in stored endocardial electrograms of modern implantable cardioverter-defibrillators (ICD) is a useful tool to classify the underlying arrhythmia leading to device therapy. Newest generations of ICD provide near- and far-field electrograms derived between various endocardial electrodes. The aim of this prospective study was to assess the quality and long-term stability of atrial signals in different far-field configurations including the active can housing. A total of 300 real-time endocardial electrogram recordings in 60 consecutive patients with a modern ICD in subpectoral position were analysed at the time of implant, pre-hospital discharge, 1, 3 and 12 months follow-up. Four different configurations were evaluated: right ventricular coil to can housing, can housing to pace/sense ring, right ventricular coil to pace/sense tip, and pace/sense tip to pace/sense ring. The best visibility of p-waves at an ECG-resolution of 0.5 mV/mm was seen in the can to coil configuration (77% of the patients). In the can to pace/sense ring electrogram p-waves could be observed in 58% of the patients. No p-waves were visible to pace/sense tip to pace/sense ring. At a resolution of 1.0 mV/mm p-waves were only visible in 10% of all patients exclusively in the can housing to right ventricular coil configuration. The results were stable (100% of the patients) over a follow-up of one year. Endocardial far-field electrograms, derived from the can housing and the right ventricular coil provide a p-wave visibility in 77% of the patients and demonstrate a long-term stability over at least one year, provided that the ECG-resolution is set at 0.5 mV/mm. Since the electrogram resolution of stored electrograms depends on the EGM-range, and the ECG-resolution at an EGM-range of 15 mV would be 1 mV/mm, the EGM-range is recommended to be programmed to 7.5 mV to ensure an ECG-resolution of at least 0.5 mV/mm for stored electrograms.