Effects of 4 Percent and 6 Percent Carboxyhemoglobin on Arrhythmia Production in Patients with Coronary Artery Disease

Dr. Sheps and colleagues assessed the effect of exposure to carbon monoxide (CO) on ventricular arrhythmias in 41 nonsmoking human volunteers with coronary artery disease. On 3 consecutive days, volunteers were exposed in random order to air, 100 ppm CO (target 4% carboxyhemoglobin), and 200 ppm CO (target 6% carboxyhemoglobin), followed by a bicycle exercise test. Radionuclide cardiac ventriculography and ambulatory electrocardiogram were performed at rest and during exercise.