Cannabis induced cardiac arrhythmias: a case series

Evidence for enduring cardiac and multiorgan toxicity after repeated exposure to the synthetic cannabinoid JWH-018 in male rats

The use of synthetic cannabinoid receptor agonists (SCRAs) represents a public health concern. Besides abuse liability and cognitive impairments, SCRA consumption is associated with serious medical consequences in humans, including cardiotoxicity. The precise mechanisms underlying cardiac or other toxicities induced by SCRAs are not well understood. Here, we used in silico, in vivo, and ex vivo approaches to investigate the toxicological consequences induced by exposure to the SCRA JWH-018. Along with in silico predictive toxicological screening of 36 SCRAs by MC4PC software, adult male Sprague-Dawley rats were repeatedly exposed to JWH-018 (0.25mg/kg ip) for 14 consecutive days, with body temperature and cardiovascular parameters measured over the course of treatment. At 1 and 7 days after JWH-018 discontinuation, multiorgan tissue pathologies and heart mitochondria bioenergetics were assessed. The in silico findings predicted risk of cardiac adverse effects specifically for JWH-018 and other aminoalkylindole SCRAs (i.e., electrocardiogram abnormality and QT prolongation). The results from rats revealed that repeated, but not single, JWH-018 exposure induced hypothermia and cardiovascular stimulation (e.g., increased blood pressure and heart rate) which persisted throughout treatment. Post-mortem findings demonstrated cardiac lesions (i.e., vacuolization, waving, edema) 1 day after JWH-018 discontinuation, which may contribute to lungs, kidneys, and liver tissue degeneration observed 7 days later. Importantly, repeated JWH-018 exposure induced mitochondrial dysfunction in cardiomyocytes, i.e., defective lipid OXPHOS, which may represent one mechanism of JWH-018-induced toxicity. Our results demonstrate that repeated administration of even a relatively low dose of JWH-018 is sufficient to affect cardiovascular function and induce enduring toxicological consequences, pointing to risks associated with SCRA consumption.

Cannabis use and incident atrial fibrillation in a longitudinal cohort

BACKGROUND

Cannabis use is increasing worldwide. While prior studies have reported an association between cannabis use and a higher risk of atrial fibrillation (AF), most were cross-sectional and generally relied on diagnostic coding to identify cannabis users, which may not be representative of the typical recreational cannabis user.

OBJECTIVE

The purpose of this study was to examine the association between recreational cannabis use and lifetime AF risk.

METHODS

We evaluated the AF risk of participants of the UK Biobank cohort who completed the cannabis use lifestyle questionnaire. Cannabis exposure was categorized as "Occasional Use" for less than 100 times used, "Frequent Use" for more than 100 times used, and "Never" users. AF events were identified using International Classification of Diseases codes. Cox models were used to estimate the hazard ratios (HRs) between cannabis use and incident AF and were subsequently adjusted for age, sex, race, alcohol, coffee, smoking, education, and baseline cardiovascular comorbidities.

RESULTS

A total of 150,554 participants (mean age 63.4 ± 7.7 years; 86,487 (57.4%) female; and 33,442 (22.2%) using cannabis at least once) were followed for a mean period of 6.1 ± 0.6 years. After multivariable adjustment, there were no statistically significant differences in incident AF among occasional users (HR 0.98; 95% confidence interval 0.89-1.08) nor frequent users (HR 1.03; 95% confidence interval 0.81-1.32) as compared with never users.

CONCLUSION

In a large prospective cohort study, there was no evidence that cannabis use was associated with a higher risk of incident AF. An evaluation of cannabis ingestion methods and quantification was not possible using the current data set.

Association between cannabis use and ten-year estimated atherosclerotic cardiovascular disease risk in a middle-aged population survey

BACKGROUND

The association between cardiovascular (CV) risk and cannabis use remains inconsistent. The purpose of this study was to examine sex stratified associations of the different lifetime aspects of cannabis use and estimated 10-year atherosclerotic cardiovascular disease (ASCVD) risk levels among the general UK Biobank population.

METHODS

Among 104,092 volunteers of the UK Biobank population, cannabis use status was assessed by questionnaire and range as heavy, moderate, low, and never users. Associations between cannabis use and ASCVD risk were estimated using multiple regressions.

RESULTS

Males presented a higher estimated 10-year ASCVD risk compared to females (7.96% vs. 2.24%, p < 0.001) and a higher proportion of heavy lifetime cannabis users (4.00% vs 2.01%, p < 0.001). In all covariate adjusted models, lifetime heavy cannabis use was associated with an increase in estimated 10-year ASCVD risk in both males and females, but with a higher effect among males (in males, B = 0.51 (0.34; 068), in females, B = 0.14 (0.05; 0.23)). When considering high estimated 10-year ASCVD risk (superior to 7.5%), similar results were observed, in males, OR=2.14 [1.82-2.51] and in females: OR=2.07 [1.35-3.17]). The current consumption of cannabis was associated with increased ASCVD risk in both males and females (p < 0.001). When considering the overall population, a significant interaction was observed between sex and cannabis use (p < 0.001).

CONCLUSION

A positive association between estimated 10-year ASCVD risk and heavy lifetime cannabis use was observed but this was higher in males. Longitudinal studies are needed in general populations to highlight the causal effects of cannabis on the atherosclerosis process.

A Case of Near-Fatal Bradycardia Caused by Accidental Cannabis Intoxication

The recreational and medicinal uses of cannabis are increasing worldwide. Given the recent legalization of marijuana in some regions of the United States, the use of edible formulations has become increasingly popular, especially among the elderly. These new formulations can be up to 10 times more potent than previously available preparations and have been associated with a variety of cardiovascular adverse effects. Here, we present a case of an elderly male who presented with dizziness and altered mental status. He was found to be severely bradycardic and emergently required atropine. Further investigation revealed that he accidentally ingested large amounts of oral cannabis. An extensive cardiac workup revealed no other etiology for his arrhythmia. Cannabidiol (CBD) and tetrahydrocannabinol (THC) are the most commonly studied cannabis compounds. With the increased access to and popularity of edible cannabis formulations, this case demonstrates the need for further research regarding the safety of oral cannabis.

The Old and the New: Cardiovascular and Respiratory Alterations Induced by Acute JWH-018 Administration Compared to Δ9-THC-A Preclinical Study in Mice

Several new psychoactive substances (NPS) are responsible for intoxication involving the cardiovascular and respiratory systems. Among NPS, synthetic cannabinoids (SCs) provoked side effects in humans characterized by tachycardia, arrhythmias, hypertension, breathing difficulty, apnoea, myocardial infarction, and cardiac arrest. Therefore, the present study investigated the cardio-respiratory (MouseOx Plus; EMKA electrocardiogram (ECG) and plethysmography TUNNEL systems) and vascular (BP-2000 systems) effects induced by 1-naphthalenyl (1-pentyl-1H-indol-3-yl)-methanone (JWH-018; 0.3-3-6 mg/kg) and Δ⁹-tetrahydrocannabinol (Δ⁹-THC; 0.3-3-6 mg/kg), administered in awake CD-1 male mice. The results showed that higher doses of JWH-018 (3-6 mg/kg) induced deep and long-lasting bradycardia, alternated with bradyarrhythmia, spaced out by sudden episodes of tachyarrhythmias (6 mg/kg), and characterized by ECG electrical parameters changes, sustained bradypnea, and systolic and transient diastolic hypertension. Otherwise, Δ⁹-THC provoked delayed bradycardia (minor intensity tachyarrhythmias episodes) and bradypnea, also causing a transient and mild hypertensive effect at the tested dose range. These effects were prevented by both treatment with selective CB₁ (AM 251, 6 mg/kg) and CB₂ (AM 630, 6 mg/kg) receptor antagonists and with the mixture of the antagonists AM 251 and AM 630, even if in a different manner. Cardio-respiratory and vascular symptoms could be induced by peripheral and central CB₁ and CB₂ receptors stimulation, which could lead to both sympathetic and parasympathetic systems activation. These findings may represent a starting point for necessary future studies aimed at exploring the proper antidotal therapy to be used in SCs-intoxicated patient management.

Accidental Ingestion of Tetrahydrocannabinol-Laced Gummies Causing Bradycardia and First-Degree Atrioventricular Block in a Pediatric Patient: A Case Report

An increasing trend of cannabis use places children at risk for the detrimental effects of marijuana. Poison control centers in the United States have been experiencing an upsurge in calls involving marijuana ingestion among children in the past years, specifically in states where marijuana is legal. With marijuana ingestion, neurologic symptoms predominate but cardiovascular manifestations have also been observed. Bradycardia and bradyarrhythmia are both uncommon cardiac manifestations of cannabis ingestion in children. Here, we present the case of a previously healthy two-year-old male with sinus bradycardia and first-degree atrioventricular (AV) block following accidental ingestion of tetrahydrocannabinol-laced gummies. Although bradycardia and first-degree AV block are uncommon after cannabis ingestion in children, clinicians should be aware of these findings and must consider evaluating for marijuana toxicity whenever presented with these acute signs. Prevention is crucial and can be achieved through supervision, parental education, and support.

Sinus Bradycardia in an Adolescent Taking Lamotrigine

Lamotrigine is commonly prescribed for the treatment of neurological conditions and is increasingly being prescribed for psychiatric conditions as well. Although largely well tolerated, it is known to have a number of potential side effects, and in March 2021, the FDA issued its most recent warning for the medication due to its increased risk of cardiac arrhythmias. In this report, we describe a case in which an adolescent patient was found to be bradycardic after starting lamotrigine for antidepressant augmentation, with a gradual return to normal heart rate as the medication was subsequently tapered and discontinued. Further research is needed to more accurately estimate the risk of cardiac side effects and to establish appropriate monitoring guidelines for cardiac arrhythmias in those taking lamotrigine.

Cannabis Use and the Risk of Cardiovascular Diseases: A Mendelian Randomization Study

Several observational studies have shown that cannabis use has negative effects on the cardiovascular system, but the causality of this relationship has not been confirmed. The aim of the current study was to estimate the effects of genetically determined cannabis use on risk of cardiovascular diseases. Ten single-nucleotide polymorphisms related to cannabis use were employed as instruments to estimate the association between genetically determined cannabis use and risk of cardiovascular diseases using a two-sample Mendelian randomization (MR) method. Summary statistics data on exposure and outcomes were obtained from different genome-wide association meta-analysis studies. The results of this MR analysis showed no causal effects of cannabis use on the risk of several common cardiovascular diseases, including coronary artery disease, myocardial infarction, stroke and ischemic stroke subtypes, atrial fibrillation (AF), and heart failure. Various sensitivity analyses yielded similar results, and no heterogeneity and directional pleiotropy were observed. After adjusting for tobacco use and body mass index, multivariable MR analysis suggested a causal effect of cannabis use on small vessel stroke (SVS) [odds ratio (OR) 1.17; 95% CI 1.02–1.35; p = 0.03] and AF (OR 1.06; 95% CI 1.01–1.10; p = 0.01), respectively. This two-sample MR study did not demonstrate a causal effect of genetic predisposition to cannabis use on several common cardiovascular outcomes. After adjusting for tobacco use and body mass index, the multivariable MR analysis suggested a detrimental effect of cannabis use on the risk of SVS and AF, respectively.