Avrio Medical

Small Heart EKG Arrhythmia Research Tool Cardiac Mapping - Microvolt Signal Acquisition Seddrak Luu George Kwei Jeff Chang Joe Ma Eric Chow Kenny Pak

Overview   Business aspect • Marketing • Cost Technical aspect • Hardware • Software

Arrhythmia  Junctional Ectopic Tachycardia • Disorders of the regular rhythmic beating of the heart • Occur in children after open heart surgery • 1 in 10 infant goes into arrhythmia after open heart surgery • Can be lethal

The Big Picture  understanding the patho-physiology of JET

Goal  a Small Heart EKG System to help understand the Arrhythmia  Focus on helping those in need rather than actual profit

Executive Team Seddrak Luu Jeff Chang Joe Ma George Kwei Eric Chow Kenny Pak

BCRI Correspondence   Dr. Glen Tibbits • Director Cardiovascular Sciences Professor of Kinesiology, Simon Fraser University (SFU) Helen Sheng (Graduate Student, MD)  Eric Lin (Graduate Student)

Other Sources of Information    Margaret Evans, • Advanced Measurements Andrew Pruszynski • Wireless Medical Devices, TA SFU Faculty • School of Kinesiology/Engineering

Structure of the Project     Signal Retrieval Stage Signal Transmission Signal Processing Signal Analysis

Avrio Core Business 1. Small Heart EKG -commercial introductions expected in a few years.

Business Based on the Product 2. Platinum Electrode Tips 3. Customize Circuitry to suit the need 4. Customize the Labview Interface

Business  Current Client • Dr. Glen Tibbits of BC Research Institute of Chilrdren’s and Women’s

Statistics     In British Columbia, ~40,000 babies were born* 600 babies are born with congenital heart disease Of that about 200 will require open heart surgery 1 in 10 will go into Arrhythmia *From Statistics Canada

Market Strategy (Short Term)  Short Term • Research Based Institute • Children Hospitals and Children Research Institute

Marketing Strategy (Long Term)  Long Term • Organization that supports the developing countries  United Nation  Unicef  Engineers / Doctors Without Borders • Aim for developing countries trying to do heart research with minimal budget

Improvements   Electrode Grid with more electrode • Increase number of electrodes per grid Tailor specific small EKG and interface for specific customer depending on the type of heart

Prototype  Total Cost: $ 751.16

• Research: $ 134.01

 Electrodes, Gel, Gel Pad • Material: $ 575.29

 Wires, Breadboard, Necessary Components • Shipping: $ 41.86

shipping cost 5.5% research 76.6% material 17.9%

Product Price for Small Heart             EKG Component 24 x AD620 4 x TL072 Capacitors / Resistors Wiring (Copper) Wiring (Platinum) Breadboard Batteries Miscellaneous and Casing NET PRODUCT PRICE Labour (6 hours) Labview Interface TOTAL Price $6.00

$1.00

$15.00

$1.00

$4.00

$20.00

$3.00

$5.00

$58.80

$72.00

$39.00

$169.80

Technical Aspects of Avrio Small Heart EKG

Heart Setup   Preparation of the heart Biology of the heart

Video of the Heart  Here we present some excerpts of the in lab trials of our designed device.

Electrodes  Initial Design Concepts/Problems • A grid system • Compact • Isolated • A flexible wrap

Electrodes

Electrodes  Final Design • Coiled platinum electrode tips • Grounded Tin Foil Shielding • Braided wires with metallic shielding

Electrodes

Challenges Incurred      Electrode Tip Size & Weight Crosstalk Interference Positioning Electrodes

Challenge: Electrode Tip     Type of material necessary Amount of surface contact Physical spacing of electrodes # of possible electrode tips

Challenge: Size & Weight     2-5 grams 1.5x1.5x1.5 cm dimensions This is a very small testing area.

We were only able to use ¼ of the heart surface for relevant probing data.

Challenge: Crosstalk    Crosstalk aka additive/subtractive signals This is caused by close proximity of the electrode Solution: • Only preventative measures such as spacing of electrode tips could be used • Future versions of systems will have software solution to this problem

Challenge: Interference  Outside electrical sources such as power lines and light bulbs   Most common is the 60Hz noise • Seen from the building power lines Solution: • Cross braiding of the electrode leads • A metal shielding from artificial light

Challenge: Positioning Electrodes    Initially we hand probed the heart as an initial step.

This was sufficient for testing but not very accurate.

Solution: • A mounting device for the electrode bundle • Needed to carefully hand manipulate the electrode tips so that they made no contact with each other.

Signal Conditioning Circuitry   Provide Gain • Heart signal is low-milli to high-micro Volt range Filtering • Get rid of noise from environment and other lab equipment

The Circuit

Circuit Design   AD620 has high Input Impedance Low power, low cost   -40dB Filter Filtering Cutoff Frequencies at 15Hz

  National Instrument BNC 2090 National Instrument AT MIO-16E-10 A/D

Labview     Testing Signal Acquisition Signal Conditioning Signal Analysis

Labview: Simulating the Heart   Generate small heart signals Generate background noise

Labview: Acquiring Data • Write data to file • Filter acquired data • Show frequency domain

Ischemia  Inverted T-wave

Bundle Branch Block •Wide QRS Complex •Caused by activation of the left ventricle prior to activation of the right ventricle

Atrial Flutter •Wide QRS complex •Inverted T-wave: Ischemia •Short PR-PR intervals •“saw tooth” pattern

Bundle Branch Block •Wide QRS Complex •Caused by activation of the left ventricle prior to activation of the right ventricle

Ventricular Tachycardia •AV dissociation, no relationship between P-wave and QRS complex •Wide QRS

Final Comments  What we learned from this: • Biological Structure of the heart • Biological Signal Processing • Signal Acquisitio • Hardware Filtering • Software Analysis

Signs of Success  We learned a lot about biology,software and hardware.

  We were able to obtain usable small signals that could be analyzed.

Finally • We started with 6 group members and we still have 6 group members. YAY!

Contacts  Company Website: www.sfu.ca/~sluu/avrio  Company Email: • [email protected]

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