The results are good news for a group of patients whose need to quit smoking is especially pressing, researchers said.

"We know continued smoking after a heart attack greatly increases the risk of a recurrent heart attack, (but) the ability of patients to quit smoking cold turkey is pretty low in general," said Dr. Kevin Woolf, a cardiologist at Hillsboro Cardiology in Oregon, who led the study.

Anti-smoking medications, such as the nicotine patch, gum, inhalers and lozenges, can double the chances that would-be quitters will actually kick the habit, said Woolf.

But, he added, there has been a theoretical concern that nicotine replacement might come with its own hazards for heart patients.

"We know that nicotine causes constriction of the arteries, which on paper could potentially harm patients with arteries in the heart that were already somewhat blocked," Woolf told Reuters Health.

To see whether nicotine replacement therapies do cause harm, Woolf and his colleagues collected medical information on 663 smokers discharged from the hospital after having acute coronary syndrome - which includes a heart attack or feeling chest pain without exercising, a condition called unstable angina.

Doctors prescribed a nicotine replacement product, in most cases the patch, to 184 of the patients.

After one year, the patients who received a prescription fared about as well as those who didn't.

Woolf and his colleagues report in the American Journal of Cardiology that 29 percent of the people in the nicotine group and 31 percent of the people in the other group died or experienced another major heart problem within a year of leaving the hospital.

"This study adds support to safely using this medication after an acute coronary syndrome," Woolf said.

Dr. Stephen Kimmel, a professor at the University of Pennsylvania, said the study backs up many cardiologists who had already considered nicotine replacement safe.

"If you've just had a heart attack or another heart event you should talk to your doctor and ask them about this therapy. Make sure you raise the issue if your doctor doesn't, because it can help you and it seems safe," said Kimmel, who was not involved in the study.

Woolf said having an anti-smoking aid available to smokers right out of the hospital is important "because it's a golden opportunity to assist them."

"When somebody comes into the hospital with a heart attack, it's a wake-up call for them," Woolf said, and they might be more willing to change their habits than later on.

The study didn't find out whether patients prescribed nicotine replacement therapy actually used it, nor whether those who were not prescribed it might have gotten their own over-the-counter nicotine replacement products.

"But we can get a sense of things," said Woolf. "Averaged over a large population, we should be able to tease out any trends that emerge from getting a prescription."

Woolf said an experiment that tracks the health of people who use nicotine replacement products, compared to the health of those who don't, would be the best measure of the medicines' safety.

SOURCE: bit.ly/MvZo0f The American Journal of Cardiology, online June 22, 2012.

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