Human cardiovascular effects of a new generation conducted electrical weapon

Objectives: The conducted electrical weapon (CEW) is used by law enforcement to control potentially violent people. Much of the research in CEW safety has focused on the TASER X26, which uses a single deployment cartridge. New Generation CEW (NGCEW) technology has been developed that uses a different circuit and multiple cartridges that can be simultaneously deployed. The objective of this study is to examine the cardiovascular effects of the NGCEW in different deployment possibilities. Methods: This was a prospective study of human subjects during NGCEW training courses. Subjects received a NGCEW probe deployment to the frontal torso in 1 of 3 configurations: 2, 3,or 4 embedded probes and then underwent a 10-s exposure. Before and after vital signs, electrocardiograms (ECGs), and serum troponin I values were obtained. Real-time echocardiography was utilized before, during and after the exposure to evaluate heart rate and rhythm. Results: Initially, a 1st version NGCEW (NGCEWv1) that was in the final stages of manufacturer verification was used at the training courses. It had not been publicly released. During a NGCEWv1 exposure with 2 probes, there was an apparent brief episode of cardiac capture. Testing was halted and the manufacturer was notified. The device was redesigned and the study continued when a redesigned, 2nd version (NGCEWv2) was used. The NGCEW1 was studied in 8 subjects. The NGCEWv2 was studied in 45 subjects with no evidence of cardiac capture. There were no important post-exposure vital sign, troponin I or ECG changes found in any volunteers. Conclusions: An apparent brief myocardial capture event occurred with the NGCEWv1. This device was not released and was redesigned. The NGCEWv2 appears to exhibit a reasonable degree of cardiac safety with frontal torso exposures and multiple probe combination configurations.