Effect of an electronic control device exposure on a methamphetamine-intoxicated animal model

Cannabis, cocaine, methamphetamine, and opiates increase the risk of incident atrial fibrillation

AIMS

Atrial fibrillation (AF) is now regarded as a preventable disease, requiring a search for modifiable risk factors. With legalization of cannabis and more lenient laws regarding the use of other illicit substances, investigation into the potential effects of methamphetamine, cocaine, opiate, and cannabis exposure on incident AF is needed.

METHODS AND RESULTS

Using Office of Statewide Health Planning and Development databases, a longitudinal analysis was performed of adult Californians ≥18 years of age who received care in an emergency department, outpatient surgery facility, or hospital from 1 January 2005 to 31 December 2015. Associations between healthcare coding for the use of each substance and a new AF diagnosis were assessed. Among 23,561,884 patients, 98 271 used methamphetamine, 48 701 used cocaine, 10 032 used opiates, and 132 834 used cannabis. Of the total population, 998 747 patients (4.2%) developed incident AF during the study period. After adjusting for potential confounders and mediators, use of methamphetamines, cocaine, opiates, and cannabis was each associated with increased incidence of AF: hazard ratios 1.86 [95% confidence interval (CI) 1.81-1.92], 1.61 (95% CI 1.55-1.68), 1.74 (95% CI 1.62-1.87), and 1.35 (95% CI 1.30-1.40), respectively. Negative control analyses in the same cohort failed to reveal similarly consistent positive relationships.

CONCLUSION

Methamphetamine, cocaine, opiate, and cannabis uses were each associated with increased risk of developing incident AF. Efforts to mitigate the use of these substances may represent a novel approach to AF prevention.

Methamphetamine Use and Cardiovascular Disease

While the opioid epidemic has garnered significant attention, the use of methamphetamines is growing worldwide independent of wealth or region. Following overdose and accidents, the leading cause of death in methamphetamine users is cardiovascular disease, because of significant effects of methamphetamine on vasoconstriction, pulmonary hypertension, atherosclerotic plaque formation, cardiac arrhythmias, and cardiomyopathy. In this review, we examine the current literature on methamphetamine-induced changes in cardiovascular health, discuss the potential mechanisms regulating these varied effects, and highlight our deficiencies in understanding how to treat methamphetamine-associated cardiovascular dysfunction.

Validity of the small swine model for human electrical safety risks

Small swine are the most common model now used for electrical safety studies. Because of the significant anatomical and electrophysiological differences and the effect of animal size on the ventricular fibrillation (VF) threshold, there are concerns that these differences may exaggerate the risks of electrical devices to humans. We chose, as an illustrative and relevant example, swine studies of the TASER® conducted electrical weapon (CEW) as it has numerous published VF studies. We reviewed the published electrical swine safety studies for CEWs and compared them to finite element modeling studies, electrical safety standards, and epidemiological experience from field usage. We also compared the body weights of the swine to those of law enforcement arrest-related deaths. Studies of small swine exaggerate the risks of CEWs to humans. This conclusion may be extrapolated to suggest that the use of small swine for electrical safety studies should be questioned in general.

Electromuscular incapacitating devices discharge and risk of severe bradycardia

Electromuscular incapacitating devices (EMDs) are high-voltage, low-current stimulators causing involuntary muscle contractions and sensory response. Existing evidence about cardiac effects of EMD remains inconclusive. The aim of our study was to analyze electrocardiographic, echocardiographic, and microvolt T-wave alternans (MTWA) changes induced by EMD discharge.

We examined 26 volunteers (22 men; median age 30 years) who underwent single standard 5-second duration exposure to TASER X26 under continuous echocardiographic and electrocardiographic monitoring. Microvolt T-wave alternans testing was performed at baseline (MTWA-1), as well as immediately and 60 minutes after EMD exposure (MTWA-2 and MTWA-3, respectively).

Mean heart rate (HR) increased significantly from 88 ± 17 beats per minute before to 129 ± 17 beats per minute after exposure (P < 0.001). However, in 2 individuals, an abrupt decrease in HR was observed. In one of them, interval between two consecutive beats increased up to 1.7 seconds during the discharge. New onset of supraventricular premature beats was observed after discharge in 1 patient. Results of MTWA-1, MTWA-2, and MTWA-3 tests were positive in one of the subjects, each time in a different case.

Standard EMD exposure can be associated with a nonuniform reaction of HR and followed by heart rhythm disturbances. New MTWA positivity can reflect either the effect of EMD exposure or a potential false positivity of MTWA assessments.

Cardiac stimulation with electronic control device application

BACKGROUND

Electronic control devices (ECDs) are weapons used to incapacitate violent subjects. Subjects have died suddenly after ECD application, but because cardiac dysrhythmias have been inconsistently observed during ECD application in animals, the cause for death is uncertain.

OBJECTIVES

The objective was to identify the factors contributing to cardiac stimulation during ECD application detected by transesophageal echocardiography.

METHODS

Four Yorkshire pigs were anesthetized, paralyzed with vecuronium, and restrained in a supine position. A GE 6T echo probe was placed in the esophagus to directly visualize left ventricular function. M-mode echocardiography was used to estimate heart rate. Two dart locations, chest and abdomen, were assessed. ECD applications were delivered from one of five commercially available devices (Taser X26, Singer S200 AT, Taser M26, Taser X3, and Taser C2) in random order to each pig, four times in each orientation.

RESULTS

Cardiac stimulation, characterized by multiple PVCs or the sudden increase in ventricular contraction rate during application, did not occur with abdominal dart location. With chest dart application in small pigs, cardiac stimulation occurred with all ECDs except with the Taser X3 (p < 0.0001). In large pigs, cardiac stimulation occurred only during chest application of the S200 AT (chest vs. abdomen: 207 beats/min, vs. 91 beats/min, p < 0.0001).

CONCLUSION

Cardiac stimulation occurs during ECD application in pigs, and is dependent upon subject size, dart orientation, and ECD. The Taser X3 did not result in cardiac stimulation in small or large pigs.

Sudden cardiac arrest and death following application of shocks from a TASER electronic control device

BACKGROUND

The safety of electronic control devices (ECDs) has been questioned. The goal of this study was to analyze in detail cases of loss of consciousness associated with ECD deployment.

METHODS AND RESULTS

Eight cases of TASER X26 ECD-induced loss of consciousness were studied. In each instance, when available, police, medical, and emergency response records, ECD dataport interrogation, automated external defibrillator information, ECG strips, depositions, and autopsy results were analyzed. First recorded rhythms were ventricular tachycardia/fibrillation in 6 cases and asystole (after ≈ 30 minutes of nonresponsiveness) in 1 case. An external defibrillator reported a shockable rhythm in 1 case, but no recording was made. This report offers evidence detailing the mechanism by which an ECD can produce transthoracic stimulation resulting in cardiac electrical capture and ventricular arrhythmias leading to cardiac arrest.

CONCLUSIONS

ECD stimulation can cause cardiac electrical capture and provoke cardiac arrest resulting from ventricular tachycardia/ventricular fibrillation. After prolonged ventricular tachycardia/ventricular fibrillation without resuscitation, asystole develops.

Multi-organ effects of Conducted Electrical Weapons (CEW) -- a review

Since the introduction of the Conducted Electrical Weapons (CEW) several studies have been conducted and multiple reports have been published on safety of these devices from a medical point of view. Use of these devices in different situations and reported deaths attracts media attention and causes general anxiety around these devices. These devices have several limitations- such as rate of fire or maximum effective range in comparison to fire arms. Here we wish to review medical publications regarding the safety of these devices based on different systems.