Gamma Variate Analysis of Pulmonary Dilution Curves for Quantitation of Left-to-Right Cardiac Shunts

Left-to-right cardiac shunts were quantified in patients with atrial septal defect using a gamma variate least squares fit to radionuclide pulmonary dilution curves. All patients were studied with cardiac catheterization. There was a close correlation between the F_p/F_s ratios obtained by oximetry in cardiac catheterization and by gamma variate analysis. The results suggest that the radionuclide dilution method is sufficiently reliable to be used as a screening test for the detection and quantitation of left-to-right cardiac shunts.

Bei Patienten mit Vorhofseptumdefekt wurde eine quantitative Bestimmung kardialer links-rechts Shunts durch eine Anpassung der pulmonalen Radionuklidverdünnungskurve an eine Gammafunktion nach der Methode der kleinsten Quadrate durchgeführt.

Alle Patienten wurden mit dem Herzkatheter untersucht. Es fand sich eine enge Korrelation zwischen den F_p/F_s-Werten, die durch die Oxymetrie bei der Herzkatheteruntersuchung und durch die Gammafunktionsanalyse erhalten wurden. Die Ergebnisse legen nahe, daß die Radionuklidverdünnungsmethode ein genügend zuverlässiger Suchtest zur Aufdeckung und quantitativen Bestimmung von kardialen links-rechts Shunts ist.

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