Diagnosis of unexpected atrial septal defect by inspired hydrogen appearance time in adult patients referred for cardiac catheterization.
Atrial septal defects may have clinical consequences regardless of their size. We evaluated the incidence of clinically unsuspected atrial septal defects in 4,411 consecutive adult patients referred for cardiac catheterization by the previously validated method of inspired hydrogen appearance time. Oximetry was performed only when an abnormally short inspired hydrogen appearance time was measured. Seventy-five patients (1.7%) were discovered to have a left-to-right shunt by this method. The shunting was at the atrial level in 65 patients. Thirty-five of these patients (0.8% of all catheterizations) were not suspected of having any form of congenital heart disease by history, physical examination, chest X-ray, EKG, or echocardiogram. In 19 cases there was no significant oxygen step-up and the diagnosis would have been missed by oximetry. The atrial septum was explored during open heart surgery in 7 patients. Atrial septal defects were detected and closed in all. Four patients had the finding confirmed by echocardiography after the catheterization. Small atrial septal defects are frequently not detected by clinical evaluation, noninvasive testing, or oximetry and are easily detected by the rapid, safe, and accurate method of inspired hydrogen appearance time.
Department of Medicine, New York University Medical Center, New York.
M E
ME
Schwinger
P A
PA
Tunick
E
E
Glassman
I
I
Kronzon
D006328:Cardiac Catheterization; D005260:Female; D006344:Heart Septal Defects, Atrial / Q000175:diagnosis*; D006801:Humans; D006859:Hydrogen; D007201:Indicator Dilution Techniques; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D012017:Referral and Consultation
D006859:Hydrogen; D010100:Oxygen