Non-invasive Assessment of Effects of Isosorbide Dinitrate on Left Ventricular Diastolic Functions and Left Atrial Systolic Time Intervals in Hypertensive Patients

Left ventricular diastolic functions and left atrial systolic time intervals (LASTI) were evaluated by Doppler echocardiography in 50 hypertensive (HG) and 25 normotensive subjects (CG) before and 20 minutes after isosorbide dinitrate (ISDN) was given. Mean and peak flow velocities (VM and VP) of early and late diastolic fillings, ratio of atrial peak flow velocity to early diastolic peak flow velocity (A/E) ratio of atrial flow volume to transmitral flow volume (AFV/TFV), and acceleration and deceleration averages (E-AA and E-DA) were measured. In addidion atrial ejection time (AET), atrial preejection time (APET) and corrected atrial preejection time (APETc) were measured as LASTI. While ISDN reduced left ventricle's and left atrium's dimensions, it also reduced left ventricular filling during early and late diastolic periods. This effect of ISDN was different in HG and CG. Although A/E and AFV/TFV ratios were fixed in HG before and after ISDN was given, they were increased significantly in CG (p<0.05). The decrease in preload was different in early and late diastoli periods when ISDN was given. The changes in preload should be noted carefully, when diastolic functions were measured by Doppler echocardiography. Because there were no significant changes occuring in APETc and APET/AET values after ISDN was given, these parameters may be used reliably in the evaluation of left atrial functions.