portable ecg collection system james cook joe konwinski carmen hayes mentor: dr. mingui sun march 15...
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Portable ECG Collection System James Cook Joe Konwinski Carmen Hayes Mentor: Dr. Mingui Sun March 15 st 2005. Outline. Introduction My Focus Specific Aims What is left to do?. Introduction. Develop a small device that can: Cleanly amplify the electric activity of the heart - PowerPoint PPT PresentationTRANSCRIPT
Portable ECG Collection SystemJames CookJoe KonwinskiCarmen Hayes
Mentor: Dr. Mingui SunMarch 15st 2005
Outline
• Introduction
• My Focus
• Specific Aims
• What is left to do?
Introduction• Develop a small device that can:
• Cleanly amplify the electric activity of the heart• Save the amplified signal onto flash memory
• Produce a program that can:• Analyze the ECG data and give heart-risk feedback
to the user
• Be sold over-the-counter• Be user-friendly and safe• Purpose: Assess heart risk of seemingly
healthy middle to upper aged individuals
My Focus
• Research methods of diagnosing heart disease via ECG
• Research ECG analysis algorithms
• Develop analysis software
Specific Aim I
ECG System:
• Normally has 12 leads, each one takes a “picture” of the heart from a different aspect.
Specific Aim I
• We will be using only 1 electrode, so a location must be chosen that collects all key parts of the waveform adequately
Specific Aim I
ECG and Heart Disease• Heart Block
• Electrical pathway from Atria to Ventricles is impaired or severed entirely
• Non-consequential or very serious depending on its extent
Specific Aim I
ECG and Heart Disease• Heart Block
•1st Degree: P-R interval > 0.2 sec•2nd Degree: Occasional lacking of
QRS wave•3rd Degree: P and QRS waves are not
coupled at all•Also Bundle Branch Block, but it’s less consequential and more difficult to diagnose
Specific Aim I
ECG and Heart Disease• Arrhythmia
• Heart Rate less than 60 or more than 100 BPM
• Periodic beat-to-beat change in P-R interval
Specific Aim II
Analyzing the ECG Waveform
• Normally done via human interpretation
• Few programmatic methods in existence
Specific Aim II
Analyzing the ECG Waveform• Triangle transformationuses statistics to pick outimportant parts of the waveform.
• Somewhat complicated and probably unnecessary
Specific Aim III
Analysis Software Development
• Preliminary data collected at 240 Hz with the amplifier.
Specific Aim III
Analysis Software Development• Data was imported
using LabVIEW.• Baseline was
calculated using a moving average filter in intervals of 1 sec.
Specific Aim III
Analysis Software Development
• Baseline was subtracted and data was filtered to remove high-frequency noise
Specific Aim III
Analysis Software Development• Peak detector algorithm run to find
locations of peaks (and valleys) as well as their amplitudes, 1st, 2nd, and 3rd derivatives
ST
R??
Q
P + noise
Specific Aim III
Analysis Software Development• Groups of data were found using an edge
detection algorithm, which will be used to isolate important parts of the waveform
Specific Aim III
Analysis Software Development• Once peaks are identified, analyzing
timing is simple!• For instance, Joe’s resting heart-rate is 78
BPM (no stethoscope required)
• This will be useful in diagnosing the aforementioned diseases and many others
What’s Left?
• More preliminary testing
• Perfect the software
• Flash memory
• Complete business plan
Questions??
Data Collection at 240 Hz:
uncompressed compressed
1 minute: 140 KB 20 KB
1 hour: 8,400 KB 1,200 KB
1 day: 201,600 KB 28,800 KB 8+ days with 256 MB chip!