I don't think this is a particularly valuable meta-analyses.
The original studies are in disagreement.
Taken individually, seven of the studies found a significant positive association between cannabis use and heart attack incidence, while four showed no significant difference and one showed a slightly negative association.
My key curiousity in this was if they separated for the user's regular method of consumption (eg smoked vs vaporized vs edible), but not only is that data not available, further the authors make clear that their pooled data could not remove confounding issues like amount of consumption nor other drug use nor tobacco.
So.. That's an awful lot of asterisks.