A technique using sintered Ag/AgCl button electrodes with controlled suction provided stable in vivo monophasic action potential recordings for up to 4 hours.
In vivo intracellular cardiac recordings using conventional glass microelectrodes to study the mechanisms of action of defibrillatory shocks are limited by electrode fragility. A technique was devised using sintered Ag/AgCl electrodes that allows multiple simultaneous monophasic action potential (MAP) recordings in vivo. Button MAP electrodes were designed that are heltonto the epicardial surface by a nylon mesh sock, with controlled application of suction used to obtain the MAP waveform. External vacuum application as well as epicardial fixation were found useful in studies of defibrillatory shocks to minimize shock hazards as well as optimize MAP reproducibility and stability. Stable recordings were obtained for 30 sec intervals every 3 minutes for periods up to 4 hours from the same epicardial site. This technique may prove useful in the in vivo determination of instantaneous activation and shock induced repolarization alterations.
Witkowski et al. (Wed,) conducted a other in Cardiac electrophysiology. Sintered Ag/AgCl button MAP electrodes with controlled suction was evaluated on Stable monophasic action potential (MAP) recordings. A technique using sintered Ag/AgCl button electrodes with controlled suction provided stable in vivo monophasic action potential recordings for up to 4 hours.