Taking a look at the report, it is interesting to note that ER visits were already on the decline in NC for the two years prior to the ban. That trend could be part of the reason for the continued decline. By raw numbers, the number of heart attacks in women actually went up. Dr. Siegel from Boston University goes into analysis in greater detail and has concerns about the conclusions drawn from this particular statistical analysis.
|From NC Tobacco Prevention and Control Report
Ed note (11/22/11): another link about tobacco control legislation and its effects from the National Conference of State Legislatures including a US map of where you can find smoking bans.