Selecting the Transthoracic Defibrillation Shock Directional Vector Based on VF Amplitude Improves Shock Success

Abstract

Choosing the defibrillation directional vector based on the largest VF amplitude improved shock success.

Programming ICDs in the Modern Era beyond Out‐of‐the Box Settings

“…Advantages of low‐energy shocks include shorter charge times, extended battery life, and possibly less myocardial damage. Nevertheless, in the modern era, charge time is not a major issue and higher energy shocks carry a greater probability of success 51,63,64 . Additional advantages of high‐energy shocks may include a higher probability of terminating inappropriately treated SVTs (for which the shock vector is suboptimal) and a slightly longer charging time that allows for ATP and favors self‐termination of nonsustained arrhythmias.…”

“…Nevertheless, in the modern era, charge time is not a major issue and higher energy shocks carry a greater probability of success. 51,63,64 Additional advantages of highenergy shocks may include a higher probability of terminating inappropriately treated SVTs (for which the shock vector is suboptimal) and a slightly longer charging time that allows for ATP and favors self-termination of nonsustained arrhythmias. Until further data are available, maximum shock outputs, especially if threshold testing was not performed, should be programmed.…”

Defibrillation Shock Amplitude, Location and Timing

“…As previously mentioned, the energy required to defibrillate the www.intechopen.com heart is much smaller during short duration ventricular fibrillation then after prolonged episodes (Section 2.2). Brooks et al demonstrated that a shock delivered in a certain direction, chosen because there was high electrogram amplitude on it, was 5-9 times more likely to be successful than other direction without high electrogram amplitude (Brooks et al, 2009). In their study, two shock directions were used: orthogonal and lateral.…”