The CVRL houses non-invasive vascular equipment designed to allow assessment of heart function, and large artery structure/function (stiffness, blood flow, remodeling/geometry) throughout the body from the aorta to the cerebral vessels. We additionally measure cognitive function as a downstream measure of brain health in order to assess relations between vascular mechanisms of brain health and cognitive function. Our noninvasive equipment (see Figure) allow us to assess:
Brain blood flow: measurement of blood flow patterns in the major intracranial cerebral arteries using Transcranial Doppler and Color Doppler ultrasound
Artery stiffness and central hemodynamics: measurement of (1) artery stiffness via gold-standard pulse wave velocity at multiple artery segments (carotid-femoral, carotid-brachial, carotid-radial) and (2) blood pressure and wave reflection at each pulse site (carotid, femoral, brachial, radial) via tonometry. By integrating pressure waves assessed via tonometry with blood velocity waveforms obtained through vascular Doppler ultrasound, we are able to calculate advanced properties of the artery and gain insght into some of the physical forces driving blood flow and wave transmission within the arteries.
Large artery hemodynamics and heart function: measurement of (1) large/conduit artery (brachial, carotid, femoral) blood flow volume and patterns via Doppler ultrasound, wave-intensity analysis, and echo-tracking, and (2) heart function and structure via cardiac ultrasound combined with left
ventricular m-mode, Doppler, tissue-Doppler and speckle-tracking.
Cognitive function: measurement of executive function and memory domains via computerized cognitive battery designed by our collaborators in Psychology. With the help of our external collaborations we are able to conduct mathematical modeling of the behavioral data to understand mechanistic changes in the underlying decision-making process.
Specific equipment used in these techniques include:
Multigon Transcranial Doppler with 2 probes and headset
Hitachi-Aloka Arietta 70 ultrasound with vascular and cardiac probes
Cardiovascular Engineering, NIHem USB 2.0 with 2 high-fidelity tonometers
Omron Automated oscillometric blood pressure cuffs
Hokansen rapid deflator cuffs
MediPines AGM100, end-tidal CO2 and pulmonary function measurement system