sodium-pertechnetate-tc-99m and Tetralogy-of-Fallot

A newborn infant with tetralogy of Fallot and absent pulmonary valve was successfully corrected in two stages. Absent pulmonary valve syndrome presenting in early infancy manifests severe respiratory symptoms that still make challenging both management and surgical treatment. This is ascribed to tracheobronchial compression by the extremely dilated pulmonary arteries, and to the resultant pulmonary obstructive lesions. We report herein the first findings of 99mTechnegas ventilation lung scanning in an infant with the syndrome to assess the pulmonary obstructive lesions.

Topics: Graphite; Humans; Infant Welfare; Infant, Newborn; Lung; Male; Pulmonary Valve; Radionuclide Imaging; Radiopharmaceuticals; Sodium Pertechnetate Tc 99m; Syndrome; Tetralogy of Fallot; Ventilation-Perfusion Ratio

With first-pass radionuclide angiography, it is possible to visualize sequentially the cardiovascular structures and to obtain computer-generated time-activity curves for regions of interest over these structures. Analysis of these curves permits the detection, localization, and quantitation of intracardiac shunts and shunts between the great arteries. The authors present the formulae used for the quantitative analysis and discuss clinical applications.

Topics: Ductus Arteriosus, Patent; Electrocardiography; Heart Defects, Congenital; Heart Septal Defects, Atrial; Heart Septal Defects, Ventricular; Hemodynamics; Humans; Infant; Infant, Newborn; Models, Cardiovascular; Postoperative Complications; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Tetralogy of Fallot; Transposition of Great Vessels

A simple, noninvasive method for measurement of right-to-left intracardiac shunts would enhance the management of patients with congenital heart disease. This study describes application of data processing techniques used previously in dye-indicator curves to data recorded during the initial transit of radioactive bolus through the central circulation. Radionuclide angiocardiograms were performed in 20 children, mean age 30 months, immediately after cardiac catheterization for congenital heart disease. The radionuclide data recorded over the carotid artery were used to replace arterial sampling required for dye indicators, and forward triangles were fitted to calculate the right-to-left shunt in an approach similar to that of Wood for indicator-dilution curves. Ten of the children had right-to-left shunts by Fick and radionuclide measurement, and 10 of the children with septal defects had no right-to-left shunt by either technique. Both the radionuclide and Fick measurements correlated well (r = 0.95). Therefore, radionuclide angiocardiographic data may be used for accurate calculation of right-to-left shunts in small children, eliminating the need for arterial sampling.

Topics: Cardiac Catheterization; Carotid Arteries; Child; Child, Preschool; Dye Dilution Technique; Female; Heart; Heart Defects, Congenital; Heart Rate; Humans; Infant; Male; Oximetry; Pulmonary Artery; Radioisotope Dilution Technique; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Technetium; Tetralogy of Fallot; Time Factors