Measurement of heterogeneous myocardial blood flow

Inert gas measurements of myocardial blood flow have been compared to simultaneous radioactive microsphere flow measurements. Average flow per unit weight agreed within 20% in 20 of 24 comparisons. With the inert gas technique flows up to 580 ml/min/100 g could be measured. Semilogarithmically plotted desaturation curves were distinctively curvilinear. It is concluded that the shape of the washout curve is a function of the underlying flow pattern.