Increased pulmonary blood volume variation in patients with heart failure compared to healthy controls: a noninvasive, quantitative measure of heart failure

This study shows that the pulmonary blood volume variation indexed to the stroke volume is higher in patients with heart failure compared with controls. The mechanisms behind this are lack of systolic suction from the left ventricular atrioventricular plane descent and increased phase shift between the in- and outflow to the pulmonary circulation (~40%), where the phase shift alone accounts for ~30%. The remaining variation (60–70%) is suggested to occur on a small vessel level.