Echocardiographic definition of left ventricular hypertrophy in the hypertensive: which method of indexation of left ventricular mass?

Objectives: It has been suggested that hypertensives at high risk of cardiovascular complications can be identified on the basis of their left ventricular mass as determined echographically. However, there is as yet a lack of consensus on the mode of indexation (body surface area, height, height(2.7)) of left ventricular mass (LVM), and on the cut-off values for definition of left ventricular hypertrophy (LVH). The main objective of this study is to test the influence of the different modes of indexation for LVM on the prevalence of LVH in a population of never treated hypertensive patients on the basis of cut-offs for LVM based upon its relationship with ambulatory blood pressure (BP) measurement. Methods: A population of 363 untreated hypertensives was investigated using a standardised procedure. The men and women were analysed separately. We studied the relationship between mean daytime ambulatory systolic BP and LVM and calculated the LVM cut-off for a BP of 135 mm Hg using three different methods of indexation. On the basis of these criteria, the population was divided into those with and those without LVH. Results: The prevalence of LVH was found to be higher when LVM was indexed to height(2.7) (50.4%) or height (50.1%). Prevalence was lowest when LVM was indexed to body surface area (48.2%), which tended to minimise the hypertrophy in obese individuals. Only indexation by height(2.7) fully compensates for relationships between height and ventricular mass in this population. Conclusions: Indexing LVM to height(2.7) thus appeared to give a more sensitive estimate of LVH by eliminating the influence of growth. Cut-offs of 47 g/m(2.7) in women and 53 g/m(2.7) in men corresponded to a cardiovascular risk indicated by a daytime systolic BP greater than or equal to 135 mm Hg.