Low-Energy Atrial Defibrillation

Abstract

T emporary epicardial wire electrodes placed during open heart surgery for potential diagnostic and/or therapeutic use in patients in the immediate postoperative period have been used safely and effectively as part of standard care for a long time. [1][2][3][4] We have also known that synchronized delivery of a low-energy DC shock for cardioversion of atrial fibrillation is very effective. [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21] With the presentation by Liebold et al 22 of the study of 100 consecutive patients undergoing open heart surgery, we now have the demonstration of a new clinical application of both the use of temporary epicardial atrial wire electrodes and low-energy DC cardioversion of atrial fibrillation. The article by Liebold et al 22 is actually about 2 things. One is a new therapeutic modality in the treatment of atrial fibrillation in the period immediately after open heart surgery. The other is the efficacy, safety, and tolerance of so-called low-energy atrial defibrillation. See p 883It is widely recognized that atrial fibrillation is a common and important problem in patients who have had open heart surgery. As recently summarized, 23 many studies have examined its potential cause(s), prevention, and treatment. Unfortunately, although these studies have provided some insights, the problem has abated little. Thus, according to the study by Liebold et al, 22 the demonstration of a new, effective treatment, low-energy atrial defibrillation with temporary epicardial wire electrodes placed on each atrium, is most welcome. The technique, initially studied in an animal model, 12,16 also permits standard use of epicardial wire electrodes for recording (diagnostic) and pacing (therapeutic and diagnostic) purposes, just as the traditional temporary epicardial atrial wire electrodes have been used in the past.1-4 Nevertheless, use of this technique does not change the problem, which is frequency of postoperative atrial fibrillation. Rather, it offers a much easier way to provide DC cardioversion of atrial fibrillation, when indicated, than the traditional delivery of a transthoracic DC shock. Early or late recurrence of atrial fibrillation notwithstanding, the technique of low-energy atrial defibrillation with temporary epicardial atrial wire electrodes should find a place in the standard treatment regimen for atrial fibrillation after open heart surgery.Perhaps the more important implications of the study by Liebold et al 22 pertain to the use of low-energy DC cardioversion of atrial fibrillation with the implantable atrial defibrillator. The use of an implantable atrial defibrillator system to deliver low-energy shocks between special catheter electrodes permanently placed in the right atrium and coronary sinus has been under systematic study for many years, first in experimental models and more recently in patients. [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21] It is clear that the device can be used successfully to defibrillate the atria in most patients with...

Recent Advances in the Non‐surgical Management of Atrial Fibrillation

“…However, more recent studies, using leads with a larger surface area, right atrial to coronary sinus configuration (Figure 6), and biphasic waveforms, have been successful 38,39 . A recent review of the world experience has shown that low energy defibrillation is feasible and safe 40 . A total of 1212 shocks was reported.…”

Estudio experimental de los efectos de la hipotermia y la hipertermia locales sobre los parámetros electrofisiológicos del miocardio y la frecuencia de activación de la fibrilación ventricular

“…Tanto la caracterización de la arritmia a partir del ECG de superficie o de los registros endocavitarios, como la predicción de los cambios en el patrón fibrilatorio inducidos por fármacos u otros procedimientos, son útiles para perfeccionar los algoritmos de identificación de la arritmia en diversas situaciones y contextos [Waldo 1998, Jetova & Mitev 2002, Kaup et al 2004.…”