OBJECTIVES: Therapeutic decisions in cardiology are frequently determined by cardiac chamber size. To decide whether cardiac dimensions are still in the normal range, reliable reference values are needed. However, published reference values mostly refer to historical cohorts using M-Mode measurements, and have not been adjusted for gender or age. The impact of body size was only vaguely addressed. The importance of such adjustments is illustrated by studies, which show that smaller individuals and females are at risk of delayed treatment and impaired outcome when currently used reference values are applied. The aim of the present study was to assess the impact of body size, gender, and age on the normal heart size.
METHODS: We prospectively studied 622 individuals (52.7% female, 17-91 years, 143-200cm, 32-240kg) without cardiac disease by standard transthoracic echocardiography. Multivariable linear regression analyses of the impact of gender, age, height, and weight, on cardiac chamber size were performed.
RESULTS: By multivariable regression analysis (n=500) all four variables independently influenced cardiac chamber size. The validity of cardiac dimensions predicted by the regression model was prospectively tested in a validation cohort (n=122). A calculator is proposed which estimates cardiac dimensions on the basis of the regression analysis.
CONCLUSIONS: Gender, height, weight, and age significantly impact on the normal heart size. These parameters need to be considered when cut-off values indicating the need for treatment or even surgery are established.