Marijuana: An Underappreciated Risk Factor for Acute Type A Aortic Dissection?

BACKGROUND Stimulants such as cocaine and amphetamines are well-established risk factors for acute aortic dissection. Despite the fact that marijuana is the most commonly used illicit drug in the United States, its relationship to acute aortic syndromes has not been well studied. METHODS A comprehensive retrospective review was undertaken of all consecutive patients who presented with acute Stanford type A aortic dissection from January 2017 to December 2019. Of 152 patients identified, 51 (33.6%) underwent comprehensive urine toxicology screening at clinical presentation. The characteristics and outcomes of the patients with urine results positive for tetrahydrocannabinol (THC) (n = 9, 17.6%) were compared with the 42 patients who had no evidence of recent marijuana consumption. RESULTS Of the 51 dissection patients who underwent broad-spectrum urine toxicology screening upon presentation, 9 (17.6%) returned positive results for THC, a proportion higher than would be expected for the general population. All THC patients were male; 3 concurrently tested positive for cocaine, and 3 others had evidence of recent amphetamine use. The THC patients were significantly younger than the non-THC patients (mean ± standard deviation age 48 ± 11.3 versus 61.4 ± 12.3 years, respectively, P = .004). A greater proportion of the THC cohort had a known diagnosis of aortic aneurysm before the dissection (44.4% versus 4.8%, P = .006). All patients underwent expeditious surgical repair. Thirty-day mortality for the entire cohort of 51 patients was 19.6% (10 deaths); for the THC group, it was 11.1% (1 death). There was no difference in the incidence of major postoperative complications between the 2 groups. CONCLUSION Marijuana is the third most commonly used substance in the United States, after alcohol and tobacco. Although marijuana use is understudied, our results suggest that marijuana may be a contributing risk factor for acute type A aortic dissection, particularly in patients with other predisposing risk factors. Given the recent national trend to legalize marijuana, with the concomitant potential for exponential increases in its consumption, we suggest that the diagnosis of aortic dissection be considered earlier in any younger patient who presents with suggestive symptoms, especially if there is a history of recent marijuana use.