A V Namugowa1, A Meeme2. 1. Physiology, Walter Sisulu University, Mthatha, South Africa. 2. Obstetrics and Gynecology, Walter Sisulu University, Mthatha, South Africa.
Abstract
INTRODUCTION: Preeclampsia is associated with arterial stiffness and endothelial dysfunction. OBJECTIVES: The aim of the study was to compare vascular function of pregnant women with preeclampsia and normotensives by non-invasive techniques. METHODS: This was a comparative study where participants were recruited from Mthatha General Hospital complex Antenatal clinics. Fifty four (54) normotensive and 21 preeclamptic women were recruited into the study. Arterial stiffness was assessed using applanation tonometry with SphygmoCor device; central aortic pressures and peripheral and central augmentation index (Alx) and carotid-femoral pulse wave velocity were then calculated. Endothelial function was assessed by EndoPAT 2000 device; pneumatic probes were fitted to the index fingers; after baseline recordings a blood pressure cuff was inflated on the non-dominant arm then released after 5min to induce flow mediated reactive hyperemia; the ratio of the readings before and after occlusion was then used to calculate the score for endothelial function; the reactive hyperaemia index (RHI) RESULTS: RHI was significantly higher; p<0.001 among preeclamptic women compared to normotensives (1.76±0.5 vs 1.45±0.22) indicating good endothelial function. Pulse wave velocity was significantly higher; p<0.001 in preeclamptic than normotensive women (6.7±1.5 vs 5.1±0.7) indicating arterial stiffness. Alx measured by the EndoPAT 2000 correlated with peripheral Alx (r=0.623, p<0.0001) and central Alx (r=0.60, p<0.0001) was measured by the SphygmoCor. This means that either of these parameters can be used to assess arterial stiffness. CONCLUSION: In this interim analysis, we have demonstrated that women with preeclampsia have increased pulse wave velocity and peripheral augmentation index suggesting vascular stiffness. Low RHI values indicate endothelial dysfunction in the general population; however our results showed a higher value in preeclampsia than in normal pregnancy. Could there be other factors responsible for RHI in pregnancy?
INTRODUCTION: Preeclampsia is associated with arterial stiffness and endothelial dysfunction. OBJECTIVES: The aim of the study was to compare vascular function of pregnant women with preeclampsia and normotensives by non-invasive techniques. METHODS: This was a comparative study where participants were recruited from Mthatha General Hospital complex Antenatal clinics. Fifty four (54) normotensive and 21 preeclamptic women were recruited into the study. Arterial stiffness was assessed using applanation tonometry with SphygmoCor device; central aortic pressures and peripheral and central augmentation index (Alx) and carotid-femoral pulse wave velocity were then calculated. Endothelial function was assessed by EndoPAT 2000 device; pneumatic probes were fitted to the index fingers; after baseline recordings a blood pressure cuff was inflated on the non-dominant arm then released after 5min to induce flow mediated reactive hyperemia; the ratio of the readings before and after occlusion was then used to calculate the score for endothelial function; the reactive hyperaemia index (RHI) RESULTS: RHI was significantly higher; p<0.001 among preeclamptic women compared to normotensives (1.76±0.5 vs 1.45±0.22) indicating good endothelial function. Pulse wave velocity was significantly higher; p<0.001 in preeclamptic than normotensive women (6.7±1.5 vs 5.1±0.7) indicating arterial stiffness. Alx measured by the EndoPAT 2000 correlated with peripheral Alx (r=0.623, p<0.0001) and central Alx (r=0.60, p<0.0001) was measured by the SphygmoCor. This means that either of these parameters can be used to assess arterial stiffness. CONCLUSION: In this interim analysis, we have demonstrated that women with preeclampsia have increased pulse wave velocity and peripheral augmentation index suggesting vascular stiffness. Low RHI values indicate endothelial dysfunction in the general population; however our results showed a higher value in preeclampsia than in normal pregnancy. Could there be other factors responsible for RHI in pregnancy?