Establishment of an Auscultation System for Arteriovenous Fistula Stenosis動靜脈瘻管聽診系統之建立

Presenter: Wei-Liang HongAdvisor: Dr. Chun-Ju Hou

OutlineProblems and RationalePurpose and Specific AimsBackground and Literatures Review Materials and MethodsPreliminary Results and DiscussionFuture worksReferences

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Problems and Rationale Incidence of renal failure and dialysis

num

ber o

f peo

ple

(mill

ions

)

Source: USRDS

2005 2006 2007 2008 2009 20100

50100150200250300350400450500

TaiwanJapanUnited StatesJalisco

Problems and Rationale Treatments for renal failure

Kidney transplantationDialysis

Peritoneal dialysis: 9.17%Hemodialysis: 90.83%

Native arteriovenous (AV) fistulaSynthetic AV shunt (Graft)

U-type transplanted fistulaLinear transplanted fistula

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Problems and Rationale

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Native AV fistula AV graft

Problems and Rationale Complications of arteriovenous fistula (AVF)

InfectionBleedingVascular access dysfunctionStenosisEmbolismSteal syndromeVenous hypertension…..

Problems and Rationale Assessments for AVF function

Palpated with the fingersStrength of pulse, thrill

AuscultationAppear high-pitched bruit or sea-gull murmur (200 ~ 800

Hz) when stenosis occursAngiographyUltrasoundCT

Problems and Rationale Problems in AVF care

Insufficient auscultation skillSubjectiveDepend on individual experience

Insufficient manpowerLack of objectively computerized sound analysis

Problems and Rationale Littmann 3200 Bluetooth Stethoscope

Frequency of 4K HzAnti-noise highTransmission for Bluetooth USD-$372.99

Purpose and Specific AimsEstablishment of an auscultation system for

the evaluation of arteriovenous fistula stenosisHardware and software designExperimental testing

Analog circuitsWavelet transform STFTFFTHilbert transform

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Yen-Nien Wang, Chih-Yang Chan, & Shi-Jun Chou, “The Detection of Arteriovenous Fistula Stenosis for Hemodialysis Based on Wavelet Transform”, International Journal of Advanced Computer Science, Vol. 1, Pp. 16-22, Jul. 2011. (Impact Factor 0.740)

Background & Literatures Review

(a) Stenosis-free representation; (b) Stenosis representation.12

Background & Literatures Review

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Stenosis-freeStenosis

Background & Literatures Review

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Stenosis-freeStenosis

Background & Literatures Review

Equipment (BIOPAC, Inc.)0.05~5k(Hz)Matlab

Analysis methodEmpirical Mode Decomposition (EMD)

Pablo V´asquez, Marco Mungu´ıa M., Members IEEE,lisabeth Mattsson, and Bengt Mandersson, “Application of the Empirical Mode Decomposition in the study ofmurmurs from Arteriovenous Fistula Stenosis”, 32nd Annual International Conference of the IEEE EMBSBuenos Aires, Argentina, August 31 - September 4, 2010

Background & Literatures Review

Equipment (BIOPAC, Inc.)MP-150 systemMatlab

Analysis methodWindkessel ModelAR modelingSTFT

Pablo V´asquez, Marco Mungu´ıa M., Members “Frequency tracking of resonant-like sounds from audio recordings of Arterio-Venous Fistula Stenosis”, 2012 IEEE International Conference on Bioinformatics and Biomedicine Workshops (BIBMW)

Background & Literatures Review

Background & Literatures ReviewCHIRPS ENCOUNTERED IN RECORDINGS.

Subject Type Signal Duration Fund. frequency [Hz]

A Fist.A1 60 225.3 ± 44.4A2 60 335.8 ± 63.7A3 60 187.6 ± 46.4

B GraftB1 60 440.9 ± 28.6B2 60 459.5 ± 44.1B3 60 485.8 ± 44.4

C Fist.C1 60 252.6 ± 66.3C2 60 265.9 ± 52.7

D Fist.

D1 60 507.6 ± 66.3D2 60 565.1 ± 111.7D3 60 493.7 ± 69.7D4 60 615.9 ± 78.4D5 60 549.9 ± 85.4

E fistulaE1 10 457.6 ± 41.9E2 10 537.3 ± 90.4