Regional diastolic function in normotensive versus hypertensive subjects: comparison using Doppler myocardial imaging

Pulsed Doppler myocardial imaging (DMI) is a new technique that makes it possible to obtain an on-line quantitative assessment of wall motion in different myocardial segments through sample-volume placement. Therefore, this tool is suitable for identifying changes in regional diastolic function in uncomplicated arterial hypertension. In this study, we examined standard Doppler-derived indexes of global left ventricular diastolic function and regional diastolic parameters obtained by pulse-wave DMI in a population of hypertensive patients, comparing them with the indexes found in a control group of normotensive subjects.

Thirty-six patients with uncomplicated hypertension and 10 normotensive subjects (all males) underwent a complete Doppler echocardiographic examination and a pulsed DMI assessment of 4 different myocardial segments: basal and middle septum, basal and middle lateral wall.

The 2 groups were comparable in age and heart rate, but body mass index, systolic and diastolic blood pressure and left ventricular mass index were higher in hypertensives. All of the transmitral diastolic measurements were impaired in hypertensives, without any difference in the Doppler indexes of global systolic function. While there were no changes in the regional systolic measurements, most of the DMI parameters for diastolic function changed significantly in all 4 of the segments examined, with a greater statistical difference at the basal and middle septum. We found a relationship between the number of segments involved in the diastolic dysfunction (ie with peak velocity E/A < 1) and the degree of impairment of the transmitral E/A ratio solely in the hypertensive population.

DMI is a useful tool for distinguishing left ventricular diastolic function in hypertensive patients and it provides information about the extent and degree of diastolic impairment in different myocardial segments. The basal and middle septum present more evident diastolic alterations. Minor but significant changes can be identified at the basal and middle lateral walls. The higher the prevalence of the myocardial segments involved in diastolic dysfunction, the greater the impairment of the global diastolic function of the left ventricle will be.