Research Projects

Twenty-six non-smoking male subjects with stable angina pectoris were studied to determine if exposing them to carbon monoxide would reduce their ability to exercise. On two separate days, subjects were exposed to either carbon monoxide (100 ppm) or to clean air in a random crossover, double blind protocol. The exposures to carbon monoxide elevated carboxyhemoglobin levels in the subjects to approximately 3%. After exposure, the subjects performed an incremental exercise stress test on a cycle ergometer until the point at which they noted the onset of angina.

The time required before the onset of angina was significantly less in subjects exercising after exposure to carbon monoxide. These results indicate that carbon monoxide exposure reduces the exercise tolerance in people with angina even at the relatively low exposure levels achieved in this study.