Splenic "disappearance" during gated exercise nuclear angiocardiography

Decreasing splenic activity occurred during the maximum exercise phase of gated stress testing in 24 patients who underwent 26 such studies. This event was related to increasing exercise, and correlated with the relative increase in heart rate, pulse-pressure product, and cardiac output, but not ejection fraction. A multiple linear regression analysis showed that the combination of increases in pulse-pressure product and cardiac output had the best correlation with decreasing splenic activity at the conclusion of exercise. Redistribution of cardiac output toward muscle and away from splanchnic viscera is a consequence of exercise, and is graphically demonstrated by decreasing splenic visualization, which in some patients was so marked as to result in disappearance of the organ from the video monitor.