Dye Dilution Curves in Congenital Heart Disease

Abstract

The need for methods capable of detecting and estimating roughly the size of congenital cardiac defects has increased with the recent rapid developments in cardiac surgery. The application of dye dilution technique to the study of these patients is largely due to the extensive work of Wood and his colleagues at the Mayo Clinic since 1950. However, although the development of these techniques represents a most valuable addition to the methods available for investigation, they are perhaps more elaborate than is possible in many smaller centres engaged in the diagnosis of congenital heart disease.Recording the passage of dye through the pinna of the transilluminated ear by a photoelectric cell and recording apparatus offers the advantage of simplicity, but has not found universal favour because of technical difficulties and lack of a suitable dye. With the development of high-stability electronic amplifiers and recorders and the introduction of Coomassie blue, we have found this method to be satisfactory for qualitative investigations. The purpose of our paper is to describe the results of this method used at the time of right heart catheterization in a series of patients with congenital heart disease, and to assess its value in clinical practice. MATERIAL AND METHODSSixty-eight unselected patients with suspected congenital heart disease were studied at rest by means of right heart catheterization ( Table I). Pressures were recorded by electromanometers and direct writing recorder. Arterial and venous blood samples were estimated for oxygen saturation by a modification of Gatman's spectrophotometric technique (Wade et al., 1953) or, if the samples had been taken after injecting dye, they were estimated by the Haldane method. The ear oximeter was based on the design of Wood and Geraci (1949) and has been used in previous work from this laboratory (Korner and Shillingford, 1955;Taylor and Shillingford, 1959).The success of the technique depends to a large extent on the recording apparatus and the design of this has presented considerable difficulty owing to the very small changes in current in the photo-electric cell during the passage of the blue dye through the ear. We have used the Cambridge earpiece and chopper amplifier, feeding either into an Evershed and Vignole 0-1 m.a. recorder or a Cambridge recorder (Fig. 1). This combination gives the high amplification and stability necessary for this method of recording. Amplifiers and recorders used in electrocardiographic or pressure recording systems have proved quite unsuitable.The sensitivity of the amplification system was arranged to give a maximum deflection of 5-7 cm. at the peak of the dilution curve, the sensitivity chosen being the highest at which a stable base line could be obtained with the patient breathing room air. After recording pressures from a chamber of the heart, blood samples were taken for determination of blood oxygen saturation and the dye was then immediately injected as rapidly as possible. The site of the injection was checked by screeni...

The Value of Dye Dilution Curves in the Diagnosis of Intracardiac Shunts

“…We agree with Oakley et al (1960) that right-to-left shunts may be shown up by dye dilution curves where arterial blood does not show any desaturation. As long as technically satisfactory curves can be obtained, even a very small shunt will show.…”

Perforation of Interventricular Septum After Myocardial Infarction

“…Other workers have confirmed these findings (Cooley et al, 1957;Gottsegen et al, 1957). The use of dye-dilution curves in our first two cases confirmed the diagnosis by showing the presence of a left-to-right shunt (Swan and Wood, 1957;Oakley et al, 1960).…”

The Two-Catheter Technique in Indicator-Dilution Cardiovascular Studies

“…Indicator dilution curves with tricarbocyanine, when recorded from the right side of the heart, provide a very accurate way to localize a left-to-right shunt Falholt and Fabricius, 1958;Oakley et al, 1960;Sanders and Morrow, 1959). With this technique, it is possible to detect a left-to-right shunt of a magnitude of 20 per cent (Fox and Wood, 1960).…”