<http://schema.org/caption>
"20. Marijuana increases heart rate by 20-100 percent shortly after smoking; this effect can last up to 3 hours. In one study, it was estimated that marijuana users have a 4.8-fold increase in the risk of heart attack in the first hour after smoking the drug."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.wgal.com/article/25-facts-about-marijuana/6156022>