Résumé : We prospectively evaluated the effects of arteriovenous fistula closure on 24-hour ambulatory blood pressure measurements and on left ventricular geometry assessed by echocardiography. Sixteen kidney transplant recipients were studied before and 1 month after surgical fistula closure. The mean of 24-hour diastolic blood pressure increased from 77+/-7 mmHg to 82+/-8 mmHg (P=0.003) without systolic changes. The diastolic blood pressure increase correlated with the reduction in left ventricular mass (P=0.0034). In multivariate analysis, the diastolic blood pressure increase best correlated with preoperative cardiac index (P=0.01). After a similar time delay between two studies, blood pressure remained unchanged in 14 kidney transplant controls with a patent fistula not scheduled for closure. Because the increase in diastolic blood pressure after arteriovenous fistula closure occurred regardless of the preoperative level of diastolic pressure, we suggest that blood pressure should be monitored after fistula closure, particularly when preoperative diastolic blood pressure is borderline or elevated.