Human Research Facility Holter Monitor (Holter) - 07.29.14
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The Human Research Facility Holter Monitor (Holter) is a battery-powered, noninvasive electrocardiogram (ECG) device that accurately measures the heart rate of crewmembers over an extended period of time (up to 24 or 48 hours). ECG information is stored on a Portable Computer Memory Card International Adapter (PCMCIA) card and downlinked to Earth for analysis after monitoring is complete.
Science Results for Everyone
Johnson Space Center, Human Research Program, Houston, TX, United States
Sponsoring Space Agency
National Aeronautics and Space Administration (NASA)
Human Exploration and Operations Mission Directorate (HEOMD)
ISS Expedition Duration
April 2006 - March 2010
Previous ISS Missions
- The Human Research Facility Holter Monitor (Holter) is a modified commercial off-the-shelf (COTS) device that accurately records the electrical activity of a crewmember's heart over an extended period of time (up to 24 or 48 hours). This noninvasive electrocardiogram (ECG) device is available to support future experiments.
- The Holter is a three-channel, seven-lead ECG that can be placed in a variety of configurations, powered by one, two, or three 9V alkaline batteries, depending on the length of recording and desired sampling rate.
- The Holter contains a removable Portable Computer Memory Card International Adapter (PCMCIA) card that allows the data to be stored, downloaded to a personal computer, and downlinked.
The Holter measures heart rates ranging from 0 to 240 beats per minute (bpm) at a sampling rate of 128 or 256 Hz. It measures ECG signals ranging from -2.5 to +2.5 mV (normal mode) and -5 to +5 mV (half-gain mode) at a sampling rate of 128 Hz or 256 Hz with an accuracy of ±2 percent of full range. The Human Research Facility (HRF) Holter accessories kit is stowed during launch and landing. Prior to using the Holter, the crewmember takes the HRF Holter accessories kit from stowage, uses the razor to shave the electrode sites, wipes the area clean with biocide wipes, and applies the electrode pads to the chest in the configuration depicted on the placard. The crewmember then dons the hardware, attaches the Holter harness to the main unit, and activates the hardware. At the end of the recording period, the crewmember deactivates, doffs, and stows the hardware. For data download, the crewmember removes the hard disk card assembly from the main unit, plugs the card into the HRF personal computer (PC), and downloads the data to the HRF PC. Downlink of the Holter data is accomplished as part of HRF rack activities.
- When in use, the Holter is placed in a Nomex pouch that is strapped around the crewmember's waist.
- An event marker on the monitor allows the subject to mark the time at which symptoms or specific activities take place. The Holter's input voltage is 5 mV (±2.5 mV from baseline) at x1.0 gain and 10 mV (±5 mV from baseline) at x0.5 gain.
- At the end of a session using the Holter, the crewmember deactivates, doffs, and stows the hardware. To download data, the crewmember removes the Portable Computer Memory Card International Adapter (PCMCIA) card, plugs the card into the Human Research Facility personal computer, and activates the data download.
Ground Based Results Publications
NASA Image: JSC2006E01969 - Astronaut Clayton Anderson trains for Expedition 14 Holter operations with instructor Ashley Weaver at the Johnson Space Center in Houston.
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