Overview
- HDVA is a proprietary, patented method and database that relates vascular function to medical conditions.
- Uses Doppler spectral data collected with FDA-approved ultrasound instruments that are in clinical use.
- Objectively classifies vascular diseases according to the vascular physiological signature.
- Quantitative, sensitive, and non-invasive.
- Being used in academic research and in clinical medical practice.
- May be used to evaluate any arterial system for early disease that may be discerned only by examining vascular performance.
History
Over the past 3 years, NHSi’s HDVA research has consisted of 6 IRB-approved trials in prominent academic research centers and 10 clinical case series at these centers or in NHSi’s clinical facility. Symptomatic data was collected from TCD laboratory facilities and asymptomatic subject data was collected within NHSi’s clinical facility, NHSCi.
The foundations of the method for HDVA were developed and tested by studying humans in extreme conditions (altitude or critically ill) or who had specific diseases to determine normal and “non-normal” profiles for HDVA. This permitted the characterization of vascular states across a broad spectrum of human cerebrovascular diseases.
Disease specific signatures were identified for Alzheimer’s dementia, hydrocephalus, sleep apnea, altitude sickness, concussion, and vasospasm (in hemorrhagic stroke). HDVA was first applied to intracranial arteries. NHSi then investigated the potential for HDVA to be extended to arteries of the neck, kidneys, legs, and heart. The effects of drugs on the cerebrovascular system were studied in small numbers of subjects. Drugs studied included Lipitor, Persantine, and blood pressure medications.
HDVA has been used by clinicians in the management of diseases such as cognitive impairment (dementia), stroke risk and evaluation of sleep apnea. The data also demonstrated the potential for HDVA to improve processes in commercial research. It quantified the heterogeneous vascular physiology that confounds clinical trials. It also demonstrated sensitivity to drug treatments and to anatomical lesions. Finally, HDVA demonstrated the ability to determine flow improvement following stent therapy – this will lay the foundation for trials to address the physiological impact (safety) of carotid stents and other endovascular procedures.