The purpose of this study was to clarify the relationship between the inferior vena cava distensibility and blood pressure. Six Japanese healthy males volunteered to participate in this study. We measured the cross-sectional area of inferior vena cava (CSAivc) and blood pressure at rest and during passive leg raising in supine position. We calculated the change rates of each parameter, based on the value at rest in supine position. We observed a negative correlation between the change rate of CSAivc and systolic blood pressure (P<0.05). These results suggest that the inferior vena cava distensibility affects partially systolic blood pressure
