Cannabis and hearts

I didn't see this one coming:

Marijuana use may result in cardiovascular-related complications—even death—among young and middle-aged adults, according to a French study reported in the Journal of the American Heart Association....

 Researchers note that marijuana use and any resulting health complications are likely underreported. There are 1.2 million regular users in France, and thus potentially a large amount of complications that are not detected by the French Addictovigilance System.