Validation of a Method for Measuring the Output of the Right Ventricle in Man by Inscription of Dye-Dilution Curves From the Pulmonary Artery

¹ From the Departments of Medicine and of Surgery, Columbia University, College of Physicians and Surgeons, and the Cardio-Pulmonary Laboratory of the First Medical and Chest Services, Columbia University Division, Bellevue Hospital, New York City

Indicator dilution curves have been inscribed through a cardiac catheter from the pulmonary artery in nine normal subjects. The suitability of these curves for measuring the right ventricular output has been investigated by comparing the calculated values of flow with those obtained from brachial arterial curves and from application of the direct Fick. The results indicate that both the pulmonary and brachial arterial flows agree with the Fick within ±15%. The advantages of using the pulmonary artery as a sampling site are stressed. These include a) the absence of a capillary bed between the injection and sampling points, and b) a considerable reduction in the contamination of the primary curve by recirculating indicator. The theoretical possibility of individually measuring the outputs of the right and left ventricles is also discussed.