Doppler echocardiographic-determined changes in left ventricular diastolic filling flow velocity during the lower body positive and negative pressure method

Abstract

Changes in parameters of left ventricular (LV) diastolic filling flow obtained with Doppler echocardiography during the lower body positive and negative pressure method were analyzed in 15 patients (12 with coronary artery disease and 3 with dilated cardiomyopathy). Lower body pressure was altered at 5 steps (+20, +10, 0, −20 and −40 mm Hg vs atmospheric pressure). Pulmonary capillary wedge pressure measured with a ballon-tipped catheter was changed proportionally with lower body pressure during the procedures (p < 0.01). Mean systemic arterial pressure was changed slightly during lower body positive pressure and negative pressure of −40 mm Hg. Heart rate was almost unchanged except at lower body pressure of −40 mm Hg. The peak velocity of LV early diastolic filling flow was changed with pulmonary capillary wedge pressure in an almost parallel fashion during the procedures (p < 0.01). The peak velocity of LV late diastolic filling flow showed smaller changes than that of early diastolic filling flow. Changes in pulmonary capillary wedge pressure correlated positively with changes in the peak velocity of LV early diastolic filling flow (r = 0.759, p < 0.01), but not with changes in the peak velocity of LV late diastolic filling flow (r = 0.039, not significant) during lower body negative pressure of −20 mm Hg. These data suggest that left atrial pressure is one of the important determinants of LV early diastolic filling flow in this acute clinical setting and that LV late diastolic filling flow is less sensitive to changes in left atrial pressure than LV early diastolic filling flow.