Stun gun and Cocaine in cardiac risk?

[Hero]

Journal of the American College of Cardiology August 8, 2006.
Two small but interesting animal studies published in the August 8, 2006 issue of the Journal of the American College of Cardiology.The first study suggests there might be cardiac risks to those subjected to stun guns, the second study finds that cocaine might protect against the induction of ventricular fibrillation (VF).In the first study, led by Dr Kumaraswamy Nanthakumar (University of Toronto, ON), investigators sought to evaluate the cardiac consequences of a stun gun (also known as neuromuscular incapacitating devices (NIDs), on the electrical function of the heart) applied to different parts of the body in an experimental porcine model.Nanthakumar and colleagues tested two commercially available stun-gun devices, differing in power and the amount of energy delivered in each pulse. Two discharge vectors, one thoracic and the other away from the chest and across the abdomen, as well as two durations of discharge, five seconds and 15 seconds, were tested.
In looking at animals in a heightened sympathetic state—after the administration of epinephrine—the investigators report 13 episodes of electrical stimulation from 16 applied electrical charges. There was one reported case of VF, and one discharge caused ventricular tachycardia among the pigs given epinephrine, likely from a shortened ventricular refraction, report investigators.
Their findings suggested that there exists the possibility of serious ventricular arrhythmia during NID discharges in structurally normal hearts during intense catecholamine stress," write Nanthakumar and colleagues. Such risks are heightened in individuals with preexisting electrophysiological abnormalities, they add.
In the second surprising study, led by Dr Dhanunjaya Lakkireddy (Cleveland Clinic, OH), investigators sought to study the effects of cocaine on VF threshold in pigs subjected to stun guns.
Investigators report there was a 1.5- to twofold increase in these values at each position after cocaine infusion, suggesting a decreased cardiac vulnerability for VF. They suggest that the true risk of arrhythmias among those under the influence of cocaine subjected to stun guns is with those who also have significant hemodynamic or metabolic disturbances, such as hypotension, hypoxemia, seizures, or myocardial ischemia/infarction. "The results of our study suggest that [neuromuscular incapacitating] NMI discharge at the standard five-second application is unlikely to cause life-threatening arrhythmias, at least in the normal heart," conclude the authors.