A Comparative Study of the Detection of Cardiovascular Shunts by Oxygen Analysis and Indicator Dilution Methods

THE RAPID ADVANCES in cardiovascular surgery have placed an added burden upon the cardiologist's diagnostic acumen. Identification and precise localization of even small shunts have become important problems in clinical medicine. Surgical cor-rection of one lesion may permit a second, previously unsuspected, lesion to reach hemodynamically significant proportions. Repair of this second lesion may not be possible at that moment for lack of pre-operative preparation for cardiopulmonary bypass. Indeed, errors in diagnosis by cardiac catheterization have led to needless thoracotomy in which the suspected lesion was not found. Recognition of the inade