Effects of short-term exposure to carbon monoxide in subjects with coronary artery disease.

Twenty-four male subjects with stable angina pectoris performed graded exercise tests after being exposed to either carbon monoxide (CO) or clean air in a randomized crossover double-blind experiment in which each subject acted as his own control. Subject's blood carboxyhemoglobin levels were increased from a baseline level of approximately 1.5% to 3% of saturation, post-CO exposure.