Although past studies have revealed the positive effects of marijuana, some experts believe the drug is not "entirely safe," especially for recreational use.

In a new study presented at the Scientific Sessions meeting of the American Heart Association, researchers revealed that active marijuana use may negatively affect a person's cardiovascular system.

In fact, the report found that active marijuana use may increase a person's risk of developing a rare type of heart condition known as stress cardiomyopathy or takotsubo.

How Marijuana Affects The Heart

Dr. Amitoj Singh, coauthor of the report and an expert from the St. Luke's University Health Network in Pennsylvania, said the effects of marijuana on the heart are not exactly "well known yet."

With the onset of marijuana legalization in the United States, Singh believes it is important for people to know how marijuana may be harmful to the heart.

Singh and his teammates began investigating the topic after they treated a patient who swallowed marijuana and was diagnosed with takotsubo.

Takotsubo or stress cardiomyopathy happens when the heart muscle weakens, reducing the heart's function to pump blood and causing shortness of breath, chest pain, fainting or dizziness.

From then on, the researchers examined federal health care records, classifying about 33,000 patients who suffered from takotsubo in 2003 to 2011 in the country. Of this number, approximately 210 patients were confirmed marijuana users.

Singh and his team found that marijuana users have double the chances as non-users to suffer a bout of takotsubo. They also had a 2.4 percent likelihood of going into cardiac arrest.

Additionally, most of the marijuana users who experienced takotsubo were young men, the researchers said. Because of this, they concluded that marijuana use increases the risk of stress cardiomyopathy among young men by a factor of two.

Extremely Rare Heart Condition

The study, however, has its limitations. Paul Armentano, who leads non-profit group NORML that lobbies for the legalization of marijuana, said the incidence of stress cardiomyopathy is extremely rare.

Armentano also pointed out that the rate of takotsubo in the study is less than 1 percent of the total number of takotsubo patients.

"[I]f cannabis consumption is a risk factor for this condition, it is a nearly insignificant risk factor," said Armentano.

Meanwhile, Singh asserts that if marijuana users experience shortness of breath or chest pain, they should visit a health care provider to make sure they are not suffering from cardiovascular problems.

"People need to know that marijuana may be harmful to the heart and blood vessels in some people," he added.