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Full text of "NASA Technical Reports Server (NTRS) 20030004818: Implantable Heart Aid"

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Implantable Heart Aid 

The latest of many spinoffs from miniaturized space 
circuitry is a tiny patient heart-assist device, implanted 
like the pacemaker, that could annually prevent 
thousands of deaths caused by the erratic heart action 
known as ventricular fibrillation. The fibrillating heart 
loses its ability to pump blood, a condition which 
causes death or permanent brain damage in a matter 
of minutes if not immediately corrected. The new 
device— called the AID™ implantable automatic pulse 
generator— monitors the heart continuously, recog- 
nizes the onset of ventricular fibrillation, and then 
delivers a corrective electrical shock. The AID pulse 
generator is, in effect, a miniaturized version of the 
defibrillator used by emergency squads and hospitals 
to restore rhythmic heartbeat after fibrillation, but it 
has the unique advantage of being permanently avail- 
able to the patient at risk. Once implanted, it needs 
no specially trained personnel nor additional equip- 
ment. Shown above, the AID system consists of a 
micro-computer, a power source and two electrodes 
which sense heart activity. 

After years of development and more than two 
years of animal and laboratory testing, the AID pulse 
generator is being clinically tested at Johns Hopkins 
University Hospital, Baltimore, Maryland. It was de- 
veloped by Medrad Incorporated and Intec Systems, 
Inc., both of Pittsburgh, Pennsylvania, in conjunction 
with Drs. M. Mirowski and M. Mower of Sinai 
Hospital and Johns Hopkins University School of 
Medicine, both of Baltimore. With NASA funding, 
Johns Hopkins’ Applied Physics Laboratory— an 
organization with extensive experience in applying 
space technology to design of implantable devices— 


conducted an independent evaluation to assure that 
the pulse generator was ready for trials in selected 
patients who have high risk of experiencing 
ventricular fibrillation. 

Applied Physics Laboratory developed an associ- 
ated system. Shown below, it includes an external 
recorder to be worn by AID patients and a physician’s 
console to display the data stored by the recorder. 
This system provides a record of fibrillation 
occurrence and the ensuing defribillation, 
information important to the physician in 
prescribing further treatment. 

™ AID is a trademark of Medrad Incorporated.