LEFT-VENTRICULAR STRUCTURE AND DETERMINANTS IN NORMOTENSIVE OFFSPRING OF ESSENTIAL HYPERTENSIVE PARENTS

Objective: To assess whether currently normotensive offspring of essential hypertensive parents may have alterations in left ventricular mass (LVM) and function, and how these relate to some potential determinants. Design and methods: Echocardiographical indices of LVM (assessed by two-dimensional guided M-mode echocardiogram), 'clinic' blood pressure and daytime ambulatory blood pressure profiles, blood pressure responses to dynamic and isometric exercise testing, haematocrit, plasma and 24-h urinary electrolytes and catecholamines, and plasma angiotensin II were assessed on a defined Na+ intake in 31 normotensive lean sons of essential hypertensive parents (OHYP group) and 30 body mass index- and age-matched sons of normotensive parents (ONORM group). Results: Clinic supine systolic blood pressure was higher in the OHYP than the ONORM group, but clinic diastolic and daytime ambulatory mean blood pressures, blood pressure loads and blood pressure during dynamic or isometric exercise did not differ significantly. LVM index (LVMI), interventricular septum thickness (IVST), posterior wall thickness (PWT), the IVST:PWT ratio, ejection fraction, fractional shortening, cardiac index and measured biochemical variables also did not differ significantly between groups. In the whole study population the LVMI correlated positively with the body mass index and negatively with plasma noradrenaline. Conclusions: In young lean men with one essential hypertensive parent and blood pressure still in the normal range, left ventricular structure and systolic function, as assessed by echocardiography, seem to be often unaltered and appropriate relative to the existing body habitus and blood pressure. Moreover, an early tendency for increasing resting blood pressure in genetically hypertension-prone humans may be more apparent under clinic than usual ambulatory conditions, whereas the blood pressure reactivity to physical stress seems to be largely normal at this stage.