Cannabis-Induced Third-Degree AV Block

Abstract

Background. Cannabis (marijuana) is the most widely consumed illicit drug in Europe. However, many are unaware of its potential cardiovascular side effects. Case Report. A 19-year-old man presented to the emergency department with palpitations and presyncope after smoking cannabis. A third-degree atrioventricular block (complete heart block) was diagnosed. We believe cannabis exposure to have been the likely cause. Extensive work-up—including Borrelia and auto-immune serology, CT coronary angiography, magnetic resonance imaging, and electrophysiological study—was negative. The patient was initially treated with IV isoprenaline. Within one day, the bradycardia spontaneously resolved. The patient was advised to quit using cannabis. No further therapy was initiated. We discuss the clinical presentation, pathophysiology, and evidence from the literature linking cannabis exposure to bradycardia. Conclusion. We describe a case of third-degree atrioventricular block after cannabis use. Emergency physicians should be aware of the potential cardiovascular side effects of this drug.

Širdies Aritmijos Ir Kanapių Vartojimas

“…Dėl adrenerginės stimuliacijos sutrumpėja kardiomiocitų veikimo potencialo trukmė bei pakinta miokardo elektrofiziologinės savybės, sudarančios palankias sąlygas padidėjusio automatizmo bei micro-reentry aritmijų patogenezei, ypač jei asmuo turi polinkį į tachiaritmijas [1, 27,28]. Didesnės kanapių dozės stimuliuoja parasimpatinę ANS, ilgėja veikimo potencialo ir prieširdžių refrakterinis periodas, galimos macro-reentry aritmijos, įvairios bradiaritmijos, silpno sinusinio mazgo sindromas (SSMS), pauzės su sinkopėmis, AV blokados [1, 15,[29][30][31][32]. Aritmijų patogenezėje svarbi ir kanapių vartojimo sąlygota miokardo išemija, padidėjęs deguonies poreikis, trombocitų aktyvacija [1,20,[33][34][35].…”

Mechanisms for the Risk of Acute Coronary Syndrome and Arrhythmia Associated With Phytogenic and Synthetic Cannabinoid Use

“…Several cases of ventricular arrhythmias, including atrioventricular block, ventricular tachycardia, and fibrillation, induced by exogenous cannabinoid use have been published. 21,22,47,48,50,53,71,[141][142][143][144][145]…”

Chronic Marijuana Consumption Leading to High-Grade Atrioventricular Block in a Young Male

“…There are several proposed mechanisms for cannabis-induced tachyarrhythmia, but it is not clear how it causes bradyarrhythmia and is primarily thought to be mediated by increased vagal tone [2]. Although, some cases of bradyarrhythmia have been described previously [3][4][5][6][7][8][9][10][11][12][13], high-grade atrioventricular (AV) block with electrophysiologic determination of the site of conduction blockade has not been reported to the best of our knowledge.…”