CLINICAL LIMITATIONS TO USE OF XENON FOR MEASUREMENT OF MYOCARDIAL BLOOD FLOW

Fifty-five patients with and without coronary artery disease were studied by selective transfemoral coronary arteriography and 133Xe myocardial blood-flow measurements. The numerical values of myocardial blood flow, as determined by the 133Xe-washout technique appeared the same in patients with and without coronary artery disease. The explanation for this finding seems to be that the 133Xe-washout technique measures myocardial blood flow per 100 Gm of myocardium. Estimation of the perfused myocardium is virtually impossible, even with the benefit of selective coronary arteriography. The practical value of this technique appears to be limited to obtaining estimations of myocardial mass from plain chest roentgenograms of normal patients without coronary artery occlusion. Since the 133Xe-washout technique allows recording of right as well as left coronary artery flow, it is considered superior to the standard nitrous-oxide technique. © Lippincott-Raven Publishers.