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Proper non-invasive assessment of carotid artery pressure ideally uses waveforms recorded at two anatomical locations: the brachial and the carotid artery. Calibrated diameter distension waveforms could provide a more widely applicable alternative for local arterial pressure assessment than applanation tonometry. This approach might be of particular use at the brachial artery, where the feasibility of a reliable tonometric measurement has been questioned. The aim of this study was to evaluate an approach based on distension waveforms obtained at the brachial and carotid arteries. This approach will be compared to traditional pulse pressures obtained through tonometry at both the carotid and brachial arteries (used as a reference) and the more recently proposed approach of combining tonometric readings at the brachial artery with linearly or exponentially calibrated distension curves at the carotid artery. Local brachial and carotid diameter distension and tonometry waveforms were recorded in 148 subjects (119 women; aged 19-59 years). The morphology of the waveforms was compared by the form factor and the root-mean-squared error. The difference between the reference carotid PP and the PP obtained from brachial and carotid distension waveforms was smaller (0.9 (4.9) mmHg or 2.3%) than the difference between the reference carotid PP and the estimates obtained using a tonometric and a distension waveform (-4.8 (2.5) mmHg for the approach using brachial tonometry and linearly scaled carotid distension, and 2.7 (6.8) mmHg when using exponentially scaled carotid distension waves). We therefore recommend to stick to one technique on both the brachial and the carotid artery, either tonometry or distension, when assessing carotid blood pressure non-invasively.

Pregnancy is a cardiovascular and metabolic challenge to the human female body. This review summarizes current knowledge on the regulation of blood pressure and plasma volume in normal and hypertensive pregnant women. During pregnancy, systemic vascular resistance and blood pressure decrease, whereas cardiac output and blood volume increase to safeguard an adequate circulation in the utero-placental arterial bed. Hypertension affects 10% of all pregnancies and is accompanied by an increase in foetal and maternal morbidity and mortality. Hypertension in pregnancy includes a wide spectrum of conditions, including pre-eclampsia and eclampsia, pre-eclampsia superimposed on chronic hypertension, chronic hypertension, and gestational hypertension. Endothelial dysfunction, oxidative stress and an exaggerated inflammatory response are features related to hypertensive disorders. Microangiopathic disorders can easily mimic hypertensive disorders during pregnancy. Although they have some symptoms in common, they require another type of management. To reduce the risk of maternal and foetal complications due to haemodynamic maladaptations, the current management includes rest at home or in the hospital, close monitoring of maternal and foetal signs and symptoms, early start of antihypertensive therapy, and timely delivery regarding maternal and foetal survival chances. Thresholds to initiate blood pressure lowering treatment during pregnancy are 160 mmHg systole or 110 mmHg diastole. Below these thresholds, treatment must be individualized because current evidence does not support aggressive medical interventions. Alpha-methyldopa and dihydropyridinic calcium channel blockers are among the recommended antihypertensives.

International audienc

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