Cerebral Vasoregulation in Elderly with Stroke

Version 1.0 - 05 October 2018

When referencing this material, please cite:

Vera Novak, Kun Hu, Laura Desrochers, Peter Novak, Louis Caplan, Lewis Lipsitz, and Magdy Selim (2010). Cerebral flow velocities during daily activities depend on blood pressure in patients with chronic ischemic infarctions. Stroke; a Journal of Cerebral Circulation, 41(1), 61–66. http://doi.org/10.1161/STROKEAHA.109.565556.

Please also include the standard citation for PhysioNet:

Goldberger AL, Amaral LAN, Glass L, Hausdorff JM, Ivanov PCh, Mark RG, Mietus JE, Moody GB, Peng C-K, Stanley HE. PhysioBank, PhysioToolkit, and PhysioNet: Components of a New Research Resource for Complex Physiologic Signals. Circulation 101(23):e215-e220 [Circulation Electronic Pages; http://circ.ahajournals.org/content/101/23/e215]; 2000 (June 13). [bib]
  author    = {Goldberger, Ary L. and Amaral, Luis A. N.
               and Glass, Leon and Hausdorff, Jeffrey M.
               and Ivanov, Plamen Ch. and Mark, Roger G.
               and Mietus, Joseph E. and Moody, George B.
               and Peng, Chung-Kang and Stanley, H. Eugene},
  title     = {{PhysioBank}, {PhysioToolkit}, and {PhysioNet}:
               Components of a New Research Resource for Complex
               Physiologic Signals},
  journal   = {Circulation},
  publisher = {American Heart Association, Inc.},
  volume    = {101},
  number    = {23},
  year      = {2000},
  month     = {June},
  pages     = {e215--e220},
  doi       = {10.1161/01.CIR.101.23.e215},
  issn      = {0009-7322},
  url       = {http://circ.ahajournals.org/content/101/23/e215}


This database contains multimodal data from a large study investigating the effects of ischemic stroke on cerebral vasoregulation. The cross sectional study compared 60 subjects who suffered strokes, to 60 control subjects, collecting the following data for each patient across multiple days: transcranial doppler of cerebral arteries, 24-h blood pressure numerics, high resolution waveforms (ECG, blood pressure, CO2 and respiration) during various movement tasks, 24-h ECG, EMG, and accelerometer recordings, and gait pressure recordings during a walking test.


Functional recovery after stroke depends upon integrity of cerebral vasoregulation. This project tested 3 hypotheses:

  1. Older adults with ischemic stroke have impaired cerebral vasoregulation, rendering cerebral blood flow dependent on blood pressure.
  2. Autonomic blood pressure control is impaired after stroke. Activities of daily living may induce hypotension, posing a risk of hypoperfusion.
  3. The distribution of impaired vasoreactivity extends beyond the infarct region into surrounding gray and white matter, affecting other vascular territories.

We investigated cerebral vasoregulation using transcranial Doppler (TCD) ultrasound and arterial spin labeling MRI at 3 Tesla, to determine the impact of stroke on cerebral blood flow regulation, autonomic 24 blood pressure control, postural control and cognition during daily living activities in older adults with and without minor stroke.

Data Collection

The full-study-protocol.docx file contains a writeup of the full experimental protocol. The day1-day2-protocol.docx file describes the data collected from the patients during the two main experimental days at the clinic.

Multiple separate sensors were used to measure patient data. The disparate sensor information was combined and synchronized. Some files in this database contain overlapping signals. No information/support will be provided regarding this process.


The open-format data files are in the data folder, which contains over 100GB of data files (not including the raw archived data), 98GB of which come from the 24h-electromyography subdirectory.

The subjects.csv file contains patient information.

The conversion folder contains an archive of the original semi-processed raw data, in proprietary and open forms including text, labview, and tff. It also contains the convert-final.ipynb Python notebook file containing the code used to convert the data to open format. The beat-to-beat blood pressure data collected using the Portapress device has not been converted into an open format. In addition, there is no MRI data from the experiments available in this database. No information/support will be provided regarding the data conversion process.

The day1-day2-protocol.docx file contains descriptions of the experiments and their relative times. The individual data files (text and wfdb) contain the starting times of the measurements. WFDB files can be read using one of the software packages.

The following folders within the data directory contain the following items (see also the day1-day2-protocol.docx file for more details):

In addition, the publications folder contains many articles published from this database


NIH-National Institute of Neurological Disorders and Stroke R01-NS045745, NIH-National Institute of Neurological Disorders and Stroke grant to Vera Novak.


For further information, please contact:

Vera Novak, MD, PhD
Associate Professor of Neurology
Dept. of Neurology, Stroke Division
Director Syncope and Falls in the Elderly Laboratory

Icon  Name                     Last modified      Size  Description
[PARENTDIR] Parent Directory - [   ] ANNOTATORS 2018-10-04 19:49 21 list of annotators [   ] RECORDS 2018-10-04 19:49 23K list of record names [DIR] conversion/ 2018-10-05 11:52 - [DIR] data/ 2018-10-04 19:50 - [   ] day1-day2-protocol.docx 2018-10-04 19:49 13K [   ] files-and-variables.xlsx 2018-10-04 19:49 638K [   ] full-study-protocol.docx 2018-10-04 19:49 24K [DIR] publications/ 2018-09-01 02:59 - [TXT] subjects.csv 2018-10-04 19:49 318K

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Updated Friday, 28 October 2016 at 16:58 EDT

PhysioNet is supported by the National Institute of General Medical Sciences (NIGMS) and the National Institute of Biomedical Imaging and Bioengineering (NIBIB) under NIH grant number 2R01GM104987-09.