Aortopulmonary collateral flow in patients with pulmonary disease.

Abstract

The aortopulmonary collateral in pulmonary disease has never been measured accurately despite many morphologic studies (1-7), which revealed numerous developments of the bronchial arteries and other systemic arteries connecting with the pulmonary vessels. To the writers' knowledge, four methods have been presented. The first (8, 9) is the detection of an increased pulmonary capillary by the indirect Fick method using carbon dioxide. The second (10) is the measurement of effective collateral flow by combined use of bronchospirometry and the Fick principle. The third ( 11-16) consists of simultaneous estimations of the right and left ventricular outputs by the indicator-dilution technique. The fourth (17, 18) is based on the concept that the early appearance of indicator in the left atrium following injection of indicator into the aortic root is carried by blood that has flowed through aortopulmonary shunts without traversing the systemic capillaries. The last method, which was proposed first by Cudkowicz and associates (17) in 1960, may be the most direct and it seems the most reliable. However, detailed information has not been available for either criticizing the method or evaluating the results. The purpose of this study was to measure the aortopulmonary collateral in various pulmonary diseases by using the direct dyedilution method and to discuss the significance of the collateral circulation.