EE497A Biomedical Signal Analysis

Jonathan Georgino

October 16th, 2009

What is Aortic Insufficiency? Also called Aortic Regurgitation

heart condition in which the valve between the left ventricle and the aorta malfunctions. This valve defect allows the pumped out blood to leak back into the heart. As a result, the left ventricle must work harder to pump more blood than normal. This increased work gradually causes the left ventricle to enlarge.

Acute aortic regurgitation —symptoms develop rapidly, and in severe cases, prompt surgery may be lifesaving

Chronic aortic regurgitation —symptoms develop over the course of many months or years

What Can Causes A.I.? Aortic valve is deformed (Birth Defect)

Disturbance near the valve affects valve’s functioning (Injury)

Risk Factors of Aortic Insufficiency Male

Age 50 or older

Congenital Heart Diseases

Infections of the Heart

High blood pressure

Symptoms of Aortic Insufficiency Shortness of breath

Fatigue

Fluid retention in certain body parts such as ankles

Heart arrhythmias

Angina (chest pains)

Hypotension (low blood pressure)

Diagnosing Aortic Insufficiency Aortic insufficiency commonly shows no symptoms for

many years. Symptoms may then occur gradually or suddenly.

Typically diagnosed at routine check-ups when doctor hears heart murmur (auscultation) and calls for additional testing.

Phonocardiogram Electrocardiogram (ECG) Echocardiogram

Treatment of Aortic Insufficiency Acute Aortic Insufficiency: requires immediate valve

replacement surgery.

Chronic Aortic Insufficiency: Doctor must monitor condition to determine ideal time for valve replacement surgery.

Decision based on

Severity of symptoms

Age

Degree of heart damage

Monitoring Aortic Insufficiency Monitoring Aortic Insufficiency is done entirely by

means of biomedical signal analysis.

Phonocardiogram ComparisonNOTE: My collected data from Denio and Harrington match the Phonocardiogram signals as demonstrated here, however my data of the Frequency Spectrum does not match, as the signals I collected contain no data in frequencies above 100Hz… also the frequencies for Aortic Insufficiency in my data are 0-20 HZ while data from Harrington are 20-40Hz – I haven’t been able to find out why my data is so different

Case Study: John XXXX Chronic Aortic

Insufficiency Diagnosed @ 14 years old

Yearly check-ups including echocardiogram & ECG

Prescribed medication (Enalapril – ACE inhibitor)

Will be receiving his data from Dubois Regional Medical Center soon

(Patient’s name has been removed. At time of study he was a 22 year old healthy male.)

Quantifying Aortic Regurgitation Aortic RegV = Aortic Regurgitation Volume

LVOT = Left Ventricle Outflow Tract

MV = Mitral Valve

Equations:Aortic RegV = LVOT flow – MV Flow

Regurgitation Fraction = Aortic RegV / LVOT Stroke Volume

Evaluating The NumbersSevere Mild

Dense continuous wave doppler signal

regurgitant volume >= 60mL

regurgitant fraction>= 55%

Faint continuous wave doppler signal

Regurgitation fraction < 30%

BIG PROBLEM! Doppler signals are difficult (and expensive) to

acquire

Even more difficult to interpret data

Only non-invasive method of determining numbers to be used in calculations

Pulsed-Wave Doppler

2-D Doppler and Color Flow Imaging

A Bump In The Road… Analysis of signals acquired contradicts my research of

what expected results should be (see slide 10 )

Phonocardiogram Signals

0 1 2 3 4 5 6-20

-10

0

10

20PCG Aortic Insufficiency

time (s)

am

plit

ude

0 1 2 3 4 5 6-20

-10

0

10

20PCG Normal

time (s)

am

plit

ude

0 10 20 30 40 50 600

2

4

6

8

10x 10

6 PSD Aortic Insufficiency

Frequency (Hz)

am

plit

ude

0 10 20 30 40 50 600

1

2

3x 10

6 PSD Normal

Frequency (Hz)

am

plit

ude

Electrocardiogram Signals

0 2 4

0

0.5

1

time (s)

am

plit

ude

ECG Aortic Insufficiency

0 2 4-1

-0.5

0

0.5

time (s)

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plit

ude

ECG Normal

0 50 100 150 2000

0.5

1

1.5

2x 10

4

Frequency (Hz)

am

plit

ude

PSD Aortic Insufficiency

0 50 100 150 2000

0.5

1

1.5

2x 10

4

Frequency (Hz)

am

plit

ude

PSD Normal

Pulse Signals

0 2 4

-20

0

20

40

60

time (s)

am

plit

ude

Pulse Aortic Insufficiency

0 2 4

0

20

40

time (s)

am

plit

ude

Pulse Normal

Goal: Understand why my acquired data is different from

research, compare to other ‘normal’ pcg and ecgsignals…

Write program in Matlab that when given an ecgsignal, it can determine if signal is of aortic insufficiency or of normal heart function. (update and say how this could be put into chip and implemented as per the abstract you wrote)