Although excessive left ventricular mass has been viewed as an adaptation to increased blood pressure, it can precede the rise in blood pressure in hypertensive models. Excessive growth of the heart may reflect additional factors contributing to eventual level of blood pressure. In children, rapid heart growth may be predictive of subsequent high childhood blood pressure level and greater incidence of cardiovascular disease in adult relatives. These studies had the potential of defining maturational changes in known risk factors which might help predict future hypertensive disease.