Relationships of the appropriateness of left ventricular mass to left atrial size and function in arterial hypertension.

OBJECTIVE

To investigate whether left ventricular mass (LVM) appropriateness may be related to left atrial changes in both size and performance in arterial hypertension.

METHODS

Three hundred and thirty-five hypertensive outpatients were studied by Doppler echocardiography and divided into two groups on the basis of LVM appropriateness. Left ventricular mass was defined inappropriate when greater than 128% of the value predicted from age, sex and stroke work (95th percentile of normal distribution) and appropriate for values <or= 128%. Left atrial volumes were obtained by two-dimensional echocardiography, left atrial ejection force was used as an index of systolic performance and calculated accordingly with Manning's formula.

RESULTS

Left ventricular mass was inappropriate in 58 patients (17%). Individuals with an inappropriate mass showed higher left atrial maximum and minimum volumes compared to those with appropriate mass (all P<0.001), independent of left ventricular geometry. Left atrial ejection fraction (44 +/- 13 versus 46 +/- 13%) and ejection force (8.4 +/- 4.8 versus 9.3 +/- 5.3 kdynes) were not statistically different between groups. In the whole group, left atrial volumes and stroke volume showed a close positive relationship with respect to crude values of LVM and inappropriate LVM, whereas left atrial ejection force was better related to left ventricular concentric geometry. This correlation was explained by the more pronounced diastolic dysfunction found in the highest quartile of left atrial ejection force.

CONCLUSIONS

In arterial hypertension, left atrial enlargement parallels an increase in LVM. Left atrial ejection force is at least in part independent of this mechanism, being mainly linked to concentric geometry and left ventricular diastolic function impairment.