According to a new study published by the Centers for Disease Control and Prevention, hospital admissions for a heart attack reduced drastically in the city of Pueblo, Colorado, after a municipal ban on smoking.

Researchers studied hospital admissions for a heart attack in Pueblo in the 18 months before the city became smoke free and compared the data post the smoking ordinance coming into effect for a similar period and three years after implementation. They found that prior to the ordinance there were 399 admissions for a heart attack and post ordinance the admission fell to 237 which was a decline of 41 %.

The Pueblo Heart Study examined data over a three year period while nine previous studies that were conducted on a similar subject were at a year or less of data after the implementation of smoke-free laws. These nine studies concluded that indoor workplaces and public areas that were smoke free were associated with sizable, rapid reductions in hospital admissions for heart attacks.

The researchers said the reduction was possibly due to a number of reasons like the reduction of second hand smoke exposure. Another reason could be that restricting smoking in public areas and the work place often resulted in the smoker quitting altogether. Secondhand smoke or the smoke that is exhaled by a smoker or is emitted from a burning cigarette or pipe has no safe levels according to the National Cancer Institute and American Cancer Society. Secondhand smoke may raise the risk of heart disease by 25 to 30 % and can have an immediate effect "on a person's heart and blood vessels."

A 2006 Surgeon General Report concluded that "exposure of adults to secondhand smoke has immediate adverse effects on the cardiovascular system and causes coronary heart disease and lung cancer." The study was published in the Centers for Disease Control and Prevention's Morbidity and Mortality Weekly Report.