The Clinical Usefulness of Hydrogen Gas as an Indicator of Left-to-Right Shunts

Abstract
In 60 patients with congenital heart disease 210 observations with hydrogen gas as an indicator for left-to-right shunts were recorded at cardiac catheterization. All but nine had other definite evidence of the presence or absence of left-to-right shunting. In these nine, 21 early hydrogen arrival times formed the only conclusive evidence of left-to-right shunting. Although hydrogen and oxygen may form a highly explosive mixture, pure hydrogen used with proper precautions is a safe, reliable, and extremely simple indicator, eminently suited as a rapid screening procedure or as a supplementary tool in cases in which left-to-right shunts are difficult to prove.