The cardiac functional reserve in elderly hypertensive patients with abnormal diurnal change in blood pressure.

Abstract

To evaluate the left ventricular function of hypertensive patients with abnormal diurnal change in blood pressure. We compared left ventricular structural and functional characteristics between hypertensive patients with a normal diurnal change in blood pressure (H2 group) and those with a nocturnal blood pressure increment (H1 group) using echocardiography. The study group consisted of 36 hypertensives and 16 normotensives whose 24-h ambulatory blood pressure monitorings were measured non-invasively. The hypertensive group was subdivided into the H1 group, consisting of 11 patients (76 +/- 7 years), and the H2 group with 25 patients (73 +/- 7 years). The normotensive control group had a mean age of 73 +/- 6 years. Echocardiographic examinations were performed before and at the end of isometric exercise (handgrip for 3 min) and isoproterenol infusion (0.02 micrograms/kg per min for 5 min). The left ventricular mass index in the H1 group was significantly greater than in the H2 or control group. Left ventricular fractional shortening (LVFS) at rest in the H1 group was also significantly greater than in the other two groups. However, the peak late: early diastolic filling ratio, which indicated diastolic function, significantly deteriorated in the H1 group compared with the H2 and control groups. Furthermore, changes in LVFS after isometric exercise in the H1 group were more suppressed than in the H2 or control group. In addition, a significantly lower increment in LVFS after isoproterenol was observed in the H1 group compared with the H2 or control group. The H1 group had greater left ventricular mass and impaired left ventricular functional reserve than the H2 group.