Gibbons John A, Mojica Andrew J, Peele Mark E
Air Force Research Laboratory, Bioeffects Division, Airman Systems Directorate, 4141 Petroleum Road, Bldg. 3260, Fort Sam Houston, TX, 78234.
KBRwyle Inc.: Science, Technology and Engineering, Department of Medicine, 4141 Petroleum Road, Bldg. 3260, Fort Sam Houston, TX, 78234.
J Forensic Sci. 2017 Nov;62(6):1516-1521. doi: 10.1111/1556-4029.13490. Epub 2017 Apr 17.
Human Electrical Muscular Incapacitation (HEMI) is used to subdue combative individuals. Changes in cardiac electrical activity have been proposed as the cause of death in a small fraction of these individuals. The current study sought to determine whether changes in QTc interval occur after HEMI exposure. Twenty-four participants had EKG readings before a 5-second HEMI exposure and within 30 min after exposure. All subject EKGs were read by a data-blinded cardiac electrophysiologist who calculated a QT corrected (QTc) interval. QTc interval was calculated using Bazett method. QTc prolongation was defined as >430 ms and a threshold of 30 ms for identifying QTc lengthening. Five participants experienced QTc prolongation and six had QTc lengthening. One participant developed QTc prolongation exceeding 500 ms, which carries a risk of developing multifocal ventricular tachycardia. These results suggest that HEMI exposure may cause EKG changes with a risk of ventricular tachycardia.
人体肌肉电失能（HEMI）被用于制服具有攻击性的个体。一小部分此类个体的死亡原因被认为是心脏电活动的变化。当前研究旨在确定在暴露于HEMI后QTc间期是否会发生变化。24名参与者在暴露于5秒HEMI之前以及暴露后30分钟内进行了心电图读数。所有受试者的心电图均由一位对数据不知情的心脏电生理学家解读，该电生理学家计算了校正QT（QTc）间期。QTc间期采用Bazett方法计算。QTc延长定义为>430毫秒，将30毫秒作为识别QTc延长的阈值。5名参与者出现QTc延长，6名参与者出现QTc间期延长。一名参与者的QTc延长超过500毫秒，这存在发生多形性室性心动过速的风险。这些结果表明，暴露于HEMI可能会导致心电图变化，并伴有室性心动过速的风险。
