Introduction
Cannabis is globally the most commonly used psychoactive substance and its use is increasing world over for both medicinal and recreational purposes.Physicians can expect to encounter more patients who use or abuse marijuana.Both acute and chronic adverse effects of cannabis on cardiovascular system like myocardial infarction, cardiomyopathy, tachyarrhythmias, stroke and cardiac arrest have been described and its consumption is a risk factor for cardiovascular disease in young adults.1The psychoactive constituent of marijuana, Δ9-tetrahydrocannabinol (THC), is an agonist of both cannabinoid receptors 1 and 2 (CB1R and CB2R), and exerts its psychoactive and adverse cardiovascular effects through the activation of CB1R in the central nervous and cardiovascular systems. There are several proposed mechanisms for cannabis induced tachyarrhythmia but how it causes bradyarrythmia is not very clear and mainly thought to be mediated by increased vagal tone. 2 Few cases of bradyarrythmia have been described previously 3-13 but reversible high grade atrio-ventricular (AV) block with electrophysiologic determination of site of conduction blockade is not reported to best of our knowledge. Our Patient presented with high grade AV block. The electro-physiological study revealed that the site of blockade was supra-his(nodal) and AV conduction completely improved at follow up, all of which support that cannabis induced bradyarrythmia are vagally mediated.