In Vivo Visualization of Intracardiac Structures With Gaseous Carbon Dioxide

Abstract

Carbon dioxide gas was injected a) intravenously, b) into the left heart, c) into the peripheral end of the carotid artery. Resulting cardiovascular and respiratory changes were observed by cinefluorography and by measurements of pressure pulses in various locations. Blood and respiratory gas changes were also observed. All changes were minimal (seconds duration) when the gas was introduced on the right or left side of the circulation. Injection into the peripheral carotid produced no untoward effects. The gas gave good visualization of valves and great vessels. Body position was not an important factor in mortality and morbidity when carbon dioxide was the gas used for contrast visualization by a cinefluorography x-ray technique. Carbon dioxide is a safe contrast medium to use for in vivo study of intracardiac structures. The gas has been used successfully by intravenous injection in human cases.