Quantitation of Valvular Regurgitation from Multiple Indicator-Dilution Curves

Abstract

Dye-dilution curves obtained simultaneously from the pulmonary artery and from the femoral artery following an intravenous injection of T 1824 or Indocyanine Green in normal subjects and in patients with nonregurgitant heart disease yielded a similar contour. This suggested that in the absence of regurgitation the parameters of the distal (arterial) curve can be predicted from the proximal (pulmonary artery) curve. The distortion of the arterial curve by regurgitation can therefore be compared with the undistorted pulmonary artery curve. To the extent that 2 identifiable and measurable flow rates exist between the sites of sampling, a theoretical basis for quantitation of the degree of valvular regurgitation may be derived.