Effects of Smoking Marihuana on Left Ventricular Performance and Plasma Norepinephrine

Abstract

In 14 healthy men we assessed the effects of smoking marihuana cigarettes containing 6 mg of delta-9-tetrahydrocannabinol on ultrasound measures of left ventricular function. Four of this group and four additional subjects also had measurements of plasma norepinephrine. Both heart rate and left ventricular performance (mean rate of internal diameter shortening [mean Vcf]) were significantly increased for at least 1 h after drug exposure compared with these values after placebo cigarettes. The immediate tachycardia and increase in mean Vcf were not accompanied by raised plasma norepinephrine levels. However, by 30 min after marihuana exposure, sympathetic neurotransmitter levels were significantly greater than both control values and those after placebo cigarettes, and they remained elevated for at least 2 h. Excessive sympathoadrenal discharge, as evidenced by augmented left ventricular function and prolonged catecholamine release, could adversely affect patients with heart disease.

Cannabis: a trigger for acute myocardial infarction? A case report

“…An increase in blood pressure, especially in the supine position, has been reported in some cases [18,19], whereas other studies reported orthostatic hypotension probably due to a reduction in autonomic reflex and in systemic vascular resistance [19,20]. An increase in sympathetic tone, reported by Gash et al [21], has been inferred from the rise in plasma norepinephrine levels [21].…”

A Unique Case of Cardiac Arrest following K2 Abuse

“…In support of this hypothesis, there is clear evidence of an arrhythmic effect of marijuana which has been linked to myocardial infarction in patients with normal coronary arteries as well as with sudden cardiac death [5, 6]. This is felt to be mediated by sympathetic nervous stimulation due to release of norepinephrine [7]. It would not be unreasonable to postulate a similar but more potent effect for synthetic cannabinoids, as they too have been found to precipitate myocardial infarction in teenagers in the absence of coronary artery disease [3].…”

Catecholaminergic polymorphic ventricular tachycardia found in an adolescent after a methylenedioxymethamphetamine and marijuana-induced cardiac arrest

“…Ylanen et al (1) report nonlethal ventricular arrhythmias in CPVT induced by tachycardia during exercise stress tests, but that syncope or sudden death is a consequence of more rapid or sustained VT or VF. Marijuana alone has been implicated with sinus tachycardia, sympathetic discharge, VT, and rarely sudden death, thus it is possible that his diagnosis was coincidental and that there was no direct correlation between the patient's drug ingestion and his CPVT (8)(9)(10). However, this patient never had arrhythmias with marijuana alone, thus synergy with the MDMA may have been required to reach a catecholamine release great enough to induce an arrhythmia (11,12).…”