[Mitral flow responses to three-week salt loading in elderly hypertensives].

Three-week effects of a high sodium diet on mitral flow pattern were assessed in 23 patients with essential hypertension (81.8 +/- 6.8 years). Transmitral flow was recorded during different rates of salt intake: 7 g/day for 8 weeks, 20 g/day for 3 weeks. With sodium loading, 19 patients whose mean blood pressure (MBP) increased by 10 percent or more were termed the salt-sensitive (SS) group, and 4 patients whose MBP did not change, or increased by less than 10 percent were termed the non salt-sensitive (NSS) group. With mitral velocity integral, cardiac output (CO) and total peripheral resistance (TPR) were calculated. Fourteen of the SS patients, in which an increase in TPR was greater than that in CO with sodium repletion, were defined as "SST". In the remaining 5 SS patients, termed "SSC", an increase in CO was greater than that in TPR with salt loading. CO increased significantly in the SSC patients, but did not change in the SST or NSS group with sodium loading. TPR increased significantly in the SST, and remained unchanged in the SSC or NSS patients. Peak velocity of transmitral flow in the rapid filling phase (R) decreased significantly in the SST patients, increased significantly in the SSC group, and remained unchanged in the NSS subjects. While, peak velocity of transmitral flow in the atrial contraction phase (A) increased significantly in the SSC group, it remained unchanged in the SST and NSS patients. There was a significant increase in A/R in the SST group and a significant decrease in A/R in the SSC patients with sodium loading.