**Conflict of interest**

None declared.

60-second post-DFE withdrawal. This may further result in abuser inhaling more DFE to sustain euphoric effect because central nervous system effects are reduced and thus lead to

Recently, Joshi et al. [66] have showed that after multiple DFE doses in rats, severe arrhythmias such as ventricular fibrillation and ventricular tachycardia can be triggered. Exposure causes significant higher amount of epinephrine release than the control group [66] and an increased sensitivity of the myocardium to epinephrine [64, 67]. Furthermore, electrolyte imbalance, cardiac biomarkers, and oxidative stress markers were significantly affected and

Alper et al. have demonstrated increase in QT duration, QT, and QTc dispersion in toluene users [68]. Toluene can cause inhibition of cardiac sodium currents like class I antiarrhythmics

Although the electrical function of the heart can be altered with acute exposure to hydrocarbons, prolonged use can cause structural damage that may also impede normal function [64]. Samples of cardiac muscle taken from inhalant abusers have shown interstitial edema, intramyocardial hemorrhages, contraction band necrosis, [70] edema, swollen and ruptured myo-

In addition to arrhythmias, halogenated hydrocarbons have negative inotropic, dromotropic, and chronotropic effects on cardiac tissue [73]. Cases of atrioventricular conduction abnor-

Cardiac arrhythmia presents a potential dangerous complication leading to sudden cardiac death threatening young population. The most important mechanisms implicated in the genesis of arrhythmia in case of illicit drug intoxication are sodium channel blockade, potassium channel blockade, catecholamine excess, and finally myocardial infarction and myocarditis. Atrial fibrillation onset in young patients without structural heart disease should pay attention to an eventual illicit drug abuse. Its identification is very important because drug cessation will protect against atrial fibrillation recurrences. **Table 1** resumes physiopathological effects and main induced arrhythmias of commonly abused illicit drugs. Management should consist, first, on withholding drug intoxication with the collaboration of a detoxification center to prevent recurrent events, and, second, on common recommended measures as for the treatment of nondrug abuse arrhythmias with respect of some particularities and contraindications as in the case of cocaine intoxication. Thus, acute management of wide QRS tachycardia related to sodium channel blockade secondary to drug abuse, include oxygenation, sedation with benzodiazepine, and hypertonic sodium bicarbonate perfusion. Class IA and class IC antiarrhythmic drugs and betablockers are classically contraindicated. Electrical cardioversion is indicated in case of all

which can cause prolonged QT interval and have proarrhythmic effects [69].

accumulation in the heart.

186 Cardiac Arrhythmias

**8. Conclusion**

can cause damage to cardiomyocytes [66].

fibrils, [71] and myocarditis and interstitial fibrosis [72].

mality have been described in toluene intoxication [74].

hemodynamically unstable arrhythmias.
