The dangers of carbon monoxide are frightening.
"Carbon monoxide attaches to the molecule in the blood that carries oxygen and it attaches instead of oxygen," said Dr. Cheryl Adkinson, an emergency medicine doctor. "So somebody who had carbon monoxide poisoning is loaded up with carbon monoxide instead of oxygen."
This makes people feel light-headed, nauseous, or they pass out. But according to a new study in the Journal of the American Medical Association, in patients with severe poisoning, carbon monoxide can also damage the heart.
Dr. Timothy Henry and colleagues at the Minneapolis Heart Institute Foundation were among those who authored the study, which was based on 230 patients with moderate to severe carbon monoxide poisoning.
"I think that the overall results of the study were very surprising," said Dr. Timothy Henry of the Minneapolis Heart Institute. "The fact that almost 40% of patients had heart damage related to the carbon monoxide poisoning, which was much higher than we expected."
And of those patients, 38% percent had died within about 7 years after their carbon monoxide poisoning, most from heart problems.
In comparison, 15% of the patients who did not have heart damage from the carbon monoxide poisoning died in that time frame.
Dr. Henry says the heart damage was a surprise, as were the long-term effects.
"Most of us believed that since this was a one-time exposure to carbon monoxide, that if you were going to have problems you'd have them right away," said Dr. Henry. "And I think that the key result of this finding is that the effect of carbon monoxide poisoning has effects not only today, but consequences down the line."
He says doctors should check patients with severe carbon monoxide poisoning for heart damage, and in some cases, give the patients medicines to protect against heart problems in the future. And he says getting a carbon monoxide detector for your home may help.
The study's authors say that in older people with heart problems, the effect of carbon monoxide poisoning was worse on the heart, but that a significant number of severe carbon monoxide poisoning patients who suffered heart damage were relatively young, and had no previous heart problems.