Left ventricular filling characteristics in sodium-depleted and sodium-loaded patients with mild essential...

To determine left ventricular early diastolic function and transmitral blood-flow characteristics during periods of sodium depletion (50 mmol/day) and sodium loading (300 mmol/day), Doppler and standard echocardiography were performed in 13 patients with untreated mild hypertension. A high sodium intake for 7 days significantly increased (P less than 0.05) the ratio of Doppler atrial contraction phase peak velocity A to rapid filling phase peak velocity R. The isovolumic relaxation time was prolonged (P less than 0.001) and the left atrial emptying index was reduced (P less than 0.05). During sodium loading the changes in isovolumic relaxation time and the atrial emptying index were correlated with the increase in mean wall stress (r = 0.600, P less than 0.05 and r = -0.695, P less than 0.01, respectively), but not with the increase in end-diastolic volume. These results suggest that during excess salt intake, left ventricular relaxation and filling may be impaired due to a salt-induced increase in afterload in patients with mild hypertension.