FLOW MEDIATED VASODILATION/VASOCONSTRICTION IN DIFFERENT DISEASE POPULATIONS

Abstract

Objective: Flow-mediated vasodilation (FMD) has become one of the most widely assessed parameter to analyze endothelial function. However, some techniques used to measure FMD have limitations. Recently, finger plethysmography (EndoPAT) failed to show any kind of reproducibility. A semi-automatic device called UNEX has been developed, which overcomes the limitation of classic systems (in particular the investigator-dependency of conventional, “hand-held” FMD measurements). We report about our first experience by using this device.Design and method: UNEX is a semi-automatic ultrasound system using an H-type ultrasound probe. This system comprised a 7.5-MHz linear array transducer and a novel stereotactic probe-holding device (UNEX EF 18G; UNEX Co., Nagoya, Japan). Another advantage of this device is the continuous recording of B-mode images and A-mode waves of the artery in the longitudinal plane, so that continuous measurement of arterial diameter in the 4.5 min following cuff deflation occurs. Finally, this semi-automatic assessment of FMD has been shown to improve the precision and repeatability of the measurement. FMD and flow mediated vasoconstriction (L-FMC) were measured in patients with heart failure, patients with estimated glomerular filtration rate less and more than 60 ml/min/1,73m2 and healthy subjects using UNEX system. Results: 67% of patients without nephropathy were patients with type 2 diabetes and 33% with hypertension. 22% of patients with nephropathy were on dialysis and 78% had an eGFR less than 60 ml/min/1,73m. Compared to other disease population patients with heart failure were older and healthy population was younger. Conclusions: Our data reveal FMD- and L-FMC values in 3 different disease populations. Updated values on FMD and L-FMC and more detailed analysis will be presented at the meeting.