Abstract 12330: Effects of Diabetes on Left Ventricular Diastolic Dysfunction in Patients with Hypertension; A Substudy of Calvloc Study
Background: Coexistence of diabetes mellitus (DM) worsens prognosis of hypertensive patients, but its mechanisms are still not fully elucidated. We previously performed a multicenter trial (CALVLOC trial) which demonstrated that a calcium channel blocker, azelnidipine, improves left ventricular (LV) relaxation in patients with hypertension and diastolic dysfunction (Hypertens Res 32;895, 2009). As a substudy of CALVLOC trial, we investigated (1) how DM would affect diastolic function in hypertensive patients (2) whether azelnidipine also would improve LV relaxation in patients with DM and hypertension.
Methods and Results: We enrolled 228 hypertensive patients with normal ejection fraction and impaired LV relaxation, as defined as early-diastolic mitral valvular velocity (e’) less than 8 cm/s. We administered 16mg of azelnidipine for 8 months (range: 6-10 month). We performed echocardiography at baseline and at 8 month later, and determined e’ and an E/e’ ratio as diastolic parameters. DM was diagnosed in 51 (22.4%) out of 228 study patients. While there were no differences in blood pressure between two groups at baseline, patients with DM (DM group) had lower e’ velocity (5.6±1.5 vs. 6.1±1.4cm/s, p=0.03) at baseline than those without DM (non-DM). There was a weak but significant correlation between e’ and HbA1c (p=0.01). No significant differences were observed in E/e’ ratio between two groups. Azelnidipine treatment lowered blood pressure similarly in two groups, and it improved e’ velocity both in the DM- (5.6±1.5 to 6.2±1.5 cm/s, p=0.0003) and in the non-DM group (6.1±1.4 to 6.7±1.4cm/s, p<0.0001). However, the DM group still had higher e’ velocity after treatment (p=0.004), and there were no differences in the degrees of improvement of e’ velocity between two groups (p=0.47).
Conclusions: DM is associated with poorer LV relaxation among the hypertensive patients in the present study. Although azelnidipine improved relaxation both in DM- and non-DM groups, the difference in e’ velocity between two groups still remained after treatment. The present results implied that comorbid DM would impair LV diastolic function independently of hypertension, which could not be corrected with antihypertensive therapy.
- © 2011 by American Heart Association, Inc.