Lub plawv zoo ECG: 7 Kauj Ruam

2024 Tus sau: John Day | [email protected]. Kawg hloov kho: 2024-01-30 09:24

Abstract

ECG, lossis electrocardiogram, yog cov cuab yeej siv kho mob feem ntau siv los sau cov cim hluav taws xob ntawm lub plawv. Lawv yooj yim los ua hauv daim ntawv yooj yim tshaj plaws, tab sis muaj ntau chav rau kev loj hlob. Txog qhov haujlwm no, ECG tau tsim thiab simulated ntawm LTSpice. ECG muaj peb ntu: ntsuas qhov ntsuas qhov ntsuas, lim qis dhau, thiab thaum kawg, lub suab tsis hloov pauv. Qhov no yog txhawm rau kom ntseeg tau tias muaj txiaj ntsig txaus los los ntawm qhov tsis muaj zog ntawm biosignal, nrog rau lub tshuab lim kom tshem suab nrov hauv Circuit Court. Cov kev sim qhia pom tias txhua feem ntawm kev ua haujlwm tau ua tiav, zoo li tau ua tag nrho cov kev sib txuas ua ke nrog tag nrho peb yam. Qhov no qhia tau tias qhov no yog txoj hauv kev tsim tau ib qho ECG Circuit. Tom qab ntawd peb tau tshawb fawb txog qhov muaj peev xwm loj rau kev txhim kho rau ECG.

Kauj ruam 1: Taw qhia/Tom qab

Ib qho ECG lossis electrocardiogram tau siv los sau cov hluav taws xob qhia ntawm lub plawv. Nws yog qhov tshwm sim ntau heev thiab tsis muaj kev sim siv los tshuaj xyuas teeb meem plawv thiab saib xyuas kev mob plawv. Lawv tau ua tiav hauv kws kho mob lub chaw haujlwm - ob lub tsev kho mob lossis chav tsev kho mob thiab yog cov tshuab zoo hauv chav ua haujlwm thiab tsheb thauj neeg mob [1]. Lawv tuaj yeem qhia pom lub plawv dhia nrawm npaum li cas, yog tias lub suab sib dhos tsis tu ncua lossis tsis, nrog rau lub zog thiab sijhawm ntawm cov hluav taws xob cuam tshuam mus los ntawm ntau qhov chaw ntawm lub plawv. Kwv yees li 12 lub tshuab hluav taws xob (lossis tsawg dua) tau txuas rau ntawm daim tawv nqaij ntawm lub hauv siab, caj npab, thiab ob txhais ceg thiab txuas nrog lub tshuab uas nyeem qhov kev xav thiab teeb tsa lawv [2]. Kaum ob-tus thawj coj ECG muaj 10 lub tshuab hluav taws xob (muab tag nrho ntawm 12 qhov kev pom ntawm lub plawv). 4-txhuas mus rau ntawm cov ceg. Ob leeg ntawm lub dab teg, thiab ob leeg ntawm pob taws. 6 qhov kawg coj mus rau ntawm lub cev. V1 mus rau ntawm qhov chaw thib plaub intercostal rau sab xis ntawm lub sternum, thaum V2 nyob ntawm tib txoj kab, tab sis sab laug ntawm lub sternum. V3 tau muab tso rau nruab nrab ntawm V2 thiab V4, V5 mus rau ntawm cov kab hauv ntej ntawm tib theem li V4 thiab V6 mus rau kab midaxillary ntawm tib qib [3].

Lub hom phiaj ntawm txoj haujlwm no yog tsim, sim, thiab txheeb xyuas qhov sib piv cov teeb liab tau txais lub cuab yeej - hauv qhov no, electrocardiogram. Txij li qhov nruab nrab lub plawv nyob ntawm 72, tab sis thaum so nws tuaj yeem mus qis li 90, qhov nruab nrab tuaj yeem txiav txim siab txog li 60 bpm, muab qhov tseem ceeb ntawm 1Hz rau lub plawv dhia. Lub plawv dhia tuaj yeem kwv yees li ntawm 0.67 txog 5 Hz (40 txog 300 bpm). Txhua lub teeb liab suav nrog nthwv dej uas tuaj yeem sau npe ua P, QRS nyuaj, thiab T feem rau nthwv dej. P nthwv dej khiav ntawm kwv yees li 0.67 - 5 Hz, QRS txoj haujlwm yog kwv yees li 10-50 Hz, thiab T nthwv dej yog li ntawm 1 - 7 Hz [4]. Lub xeev tam sim no ntawm kev kos duab ECGs muaj tshuab kev kawm [5], qhov twg arrhythmias thiab zoo li tuaj yeem cais los ntawm lub tshuab nws tus kheej. Txhawm rau kom yooj yim dua, ECG no yuav tsuas muaj ob qhov hluav taws xob - qhov zoo thiab qhov tsis zoo.

Kauj Ruam 2: Cov Txheej Txheem thiab Cov Khoom

Txhawm rau pib tsim, lub khoos phis tawj tau siv rau ob qho kev tshawb fawb thiab ua qauv. Lub software siv yog LTSpice. Ua ntej, los tsim cov phiaj xwm rau analog ECG, kev tshawb fawb tau ua tiav los saib seb cov qauv tsim tam sim no yog dab tsi thiab yuav ua li cas thiaj ua tau zoo tshaj plaws rau hauv kev tsim qauv tshiab. Zoo nkauj npaum li txhua lub hauv paus tau pib nrog lub ntsuas qhov ntsuas kom pib. Nws siv ob qhov kev nkag mus - los ntawm txhua qhov hluav taws xob. Tom qab ntawd, qhov ntsuas qis dhau tau xaiv kom tshem tawm cov cim tshaj 50 Hz, txij li lub zog hluav taws xob suab nrov tuaj txog ntawm 50-60 Hz [6]. Tom qab ntawd, yog lub suab tsis hloov pauv kom nthuav dav lub teeb liab, vim biosignals me me heev.

Thawj qhov kev tivthaiv yog qhov ntsuas qhov ntsuas. Nws muaj ob lub tswv yim, ib qho rau qhov zoo thiab ib qho rau qhov tsis zoo electrode. Cov cuab yeej siv suab nrov tau siv tshwj xeeb los tiv thaiv lub Circuit Court los ntawm cov teeb liab tuaj. Muaj peb qho thoob ntiaj teb op-amps thiab 7 tus tiv thaiv. Txhua tus tiv thaiv tab sis R4 (Rgain) yog tib qhov kev tawm tsam. Qhov nce ntawm qhov ntsuas qhov ntsuas tuaj yeem siv nrog cov kab zauv hauv qab no: A = 1 + (2RRgain) [7] Qhov nce tau raug xaiv los ua 50 vim tias biosignals me me heev. Cov resistors tau xaiv los ua kom loj dua rau kev yooj yim siv. Kev suav tom qab ua raws cov txheej txheem no muab R = 5000Ω thiab Rgain = 200Ω. 50 = 1 + (2RRgain) 50 2 * 5000200

Cov khoom siv tom ntej siv yog lim qis, tshem tawm cov zaus ntau dua 50 Hz, uas yuav ua rau PQRST nthwv dej hauv qhov ntau zaus no thiab txo qis suab nrov. Qhov sib npaug rau qhov lim qis dhau los tau qhia hauv qab no: fc = 12RC [8] Txij li qhov xaiv zaus rau kev txiav tawm yog 50 Hz, thiab tus tiv thaiv raug xaiv los ua 1kΩ, cov lus teb tau muab tus nqi hluav taws xob ntawm 0.00000318 F. 50 = 12 * 1000 * C ib

Qhov tivthaiv thib peb hauv ECG yog lub suab tsis hloov pauv. Qhov no yog kom ntseeg tau tias lub teeb liab loj txaus ua ntej (muaj peev xwm) raug xa mus rau qhov sib piv rau digital hloov pauv. Qhov tau txais ntawm lub suab tsis hloov pauv tau qhia hauv qab no: A = 1 + R2R1 [9] Zoo li ua ntej qhov nce tau xaiv los ua 50, txhawm rau nce qhov dav ntawm qhov teeb meem zaum kawg. Cov lus teb rau tus tiv thaiv yog raws li hauv qab no, nrog rau ib tus resistor xaiv ua 10000Ω, muab tus nqi tiv thaiv thib ob ntawm 200Ω. 50 = 1 + 10000R1 50 10000200

Txhawm rau sim cov phiaj xwm, kev tshuaj xyuas tau ua haujlwm ntawm txhua qhov kev sib txuas thiab tom qab ntawd qhov kawg ntawm cov txheej txheem tag nrho. Qhov kev sim thib ob yog kev tshuaj xyuas AC, kev cheb octave, nrog 100 cov ntsiab lus ntawm ib lub octave, thiab khiav hla zaus 1 txog 1000 Hz.

Kauj Ruam 3: Cov txiaj ntsig

Txhawm rau sim lub Circuit Court, kev ua haujlwm octave tau ua tiav, nrog 100 cov ntsiab lus ntawm ib lub octave, pib nrog zaus ntawm 1 Hz, thiab mus txog rau zaus ntawm 1000 Hz. Cov tswv yim yog qhov nkhaus sinusoidal, los ua tus sawv cev ntawm qhov xwm txheej ntawm ECG yoj. Nws muaj DC offset ntawm 0, amplitude ntawm 1, zaus ntawm 1 Hz, T ncua ntawm 0, theta (1/s) ntawm 0, thiab phi (deg) ntawm 90. Qhov zaus tau teeb tsa ua 1, txij li qhov nruab nrab lub plawv tuaj yeem teev txog 60 bpm, uas yog 1 Hz.

Raws li pom hauv daim duab 5, xiav yog lub tswv yim thiab liab yog qhov tso tawm. Muaj kom meej meej nce loj heev, raws li pom saum toj no.

Lub lim qis dhau tau teeb tsa rau 50 Hz, txhawm rau tshem tawm cov kab hluav taws xob nrov hauv qhov muaj peev xwm thov ECG. Txij li qhov ntawd tsis siv ntawm no qhov chaw teeb liab tas li ntawm 1 Hz, cov zis yog tib yam li cov tswv yim (Daim duab 6).

Cov zis - pom hauv xiav - tau hais meej meej meej hauv kev sib piv rau cov tswv yim, pom hauv ntsuab. Ib qho ntxiv, txij li qhov siab thiab hav ntawm txoj kab nkhaus sine sib phim, qhov no qhia tau hais tias lub suab nrov nrov tsis yog hloov pauv (Daim duab 7).

Daim duab 8 qhia tag nrho cov nkhaus ua ke. Nws qhia meej qhia txog kev tswj hwm lub teeb liab, mus los ntawm lub teeb liab me me, ua kom nrov dua ob zaug, thiab lim (txawm hais tias pom tsis muaj kev cuam tshuam rau lub teeb liab tshwj xeeb no).

Siv qhov sib npaug kom tau txais thiab txiav tawm zaus [10, 11], cov txiaj ntsig sim tau txiav txim siab los ntawm cov phiaj. Cov lim qis dhau muaj qhov yuam kev tsawg tshaj plaws, thaum ob lub tshuab ua suab nrov nrog qhov ua yuam kev kwv yees li 10% (Table 1).

Kauj ruam 4: Sib tham

Nws zoo nkaus li cov txheej txheem ua dab tsi nws yuav tsum ua. Nws tau txais lub teeb liab muab, ua kom nrov nrov, tom qab ntawd lim nws, thiab tom qab ntawd ua kom nrov dua. Qhov ntawd tau hais, nws yog qhov tsim 'me me', tsuas yog siv lub tshuab ntsuas qhov ntsuas, lim qis dhau, thiab lim uas tsis hloov pauv. Tsis muaj lub tswv yim meej ntawm ECG qhov chaw, txawm hais tias suav tsis txheeb cov sij hawm caij nthwv lub vev xaib rau qhov chaw tsim nyog. Hmoov tsis zoo, thaum qhov ntawd tsis ua haujlwm, kev ua txhaum nthwv dej yog qhov tsim nyog hloov pauv rau qhov xwm txheej sib txawv ntawm lub teeb liab.

Lub hauv paus ntawm qhov ua yuam kev thaum nws los txog rau theoretical thiab tus nqi tiag ntawm qhov nce thiab qis lim lim tuaj yeem yog cov khoom xaiv. Txij li cov kev sib npaug siv tau muaj qhov sib piv ntawm qhov kev tawm tsam ntxiv rau 1, thaum ua cov lej, qhov no tau raug tsis quav ntsej. Qhov no tuaj yeem ua tiav yog tias cov resistors siv loj txaus. Thaum cov resistors xaiv tau loj, qhov tseeb tias ib tus tsis raug coj mus rau hauv kev suav yuav tsim qhov me me ntawm qhov ua yuam kev. Cov kws tshawb fawb ntawm San Jose State University hauv San Jose CA tsim ECG tshwj xeeb rau kev kuaj mob kab mob plawv. Lawv tau siv lub tshuab ntsuas qhov ntsuas, 1st xaj kom muaj lub siab lim siab tshaj plaws, qhov kev txiav txim zaum thib 5 ua haujlwm Bessel qis dhau tus muab tub lim, thiab tus ntxaib-t nquag thais lim [6]. Lawv xaus lus tias kev siv tag nrho cov khoom siv no ua rau muaj kev ua tiav ntawm ECG nyoos yoj los ntawm tib neeg kev kawm. Lwm tus qauv ntawm qhov yooj yim ECG Circuit ua los ntawm Orlando Hoilett ntawm Purdue University tsuas yog siv cov cuab yeej siv suab nrov. Cov zis tau pom meej thiab siv tau, tab sis nws tau pom zoo tias rau cov ntawv thov tshwj xeeb, kev hloov pauv yuav zoo dua - piv txwv li lub tshuab ua kom nrov nrov, cov lim bandpass, thiab 60 Hz thais lim kom tshem tawm cov kab hluav taws xob suab nrov. Qhov no qhia tau hais tias qhov kev tsim qauv ntawm ECG, thaum tsis yog txhua qhov, tsis yog txoj hauv kev yooj yim tshaj plaws ntawm kev ua hauv ECG teeb liab.

Kauj Ruam 5: Ua Haujlwm Yav Tom Ntej

Qhov kev tsim ntawm ECG yuav xav tau ob peb yam ntxiv ua ntej yuav muab tso rau hauv cov cuab yeej siv tau. Rau ib qho, 60 Hz thais lim tau pom zoo los ntawm ntau qhov chaw, thiab txij li thaum tsis muaj kab hluav taws xob suab nrov los cuam tshuam nrog ntawm no, nws tsis tau siv rau hauv kev sim. Uas tau hais tias, thaum qhov no tau txhais rau lub cuab yeej siv lub cev, nws yuav muaj txiaj ntsig zoo ntxiv rau lub ntsej muag lim. Ib qho ntxiv, tsis txhob siv lub lim qis dhau, nws yuav ua haujlwm zoo dua kom muaj lub lim bandpass, kom muaj kev tswj hwm ntau zaus uas tab tom raug lim tawm. Ib zaug ntxiv, hauv kev sim, qhov teeb meem no tsis tshwm sim, tab sis nws yuav tshwm sim hauv lub cev. Tom qab qhov no, ECG yuav xav tau qhov sib piv rau hloov pauv digital, thiab yuav zoo li lub cuab yeej zoo ib yam li raspberry pi txhawm rau khaws cov ntaub ntawv thiab tso nws mus rau lub khoos phis tawj saib thiab siv. Kev txhim kho ntxiv yuav yog qhov ntxiv ntawm kev coj ua ntau dua, tej zaum pib nrog 4 txoj kev coj mus thiab kawm tiav rau tag nrho 10 txoj hauv kev rau 12 daim duab qhia lub plawv. Kev siv tus neeg siv zoo dua kuj tseem yuav muaj txiaj ntsig - tej zaum nrog lub vijtsam kov rau cov kws kho mob kom tuaj yeem nkag tau yooj yim thiab tsom mus rau qee qhov ntawm ECG cov zis.

Cov kauj ruam txuas ntxiv yuav cuam tshuam nrog kev kawm tshuab thiab siv AI. Lub khoos phis tawj yuav tsum muaj peev xwm ceeb toom cov neeg ua haujlwm kho mob - thiab tej zaum cov neeg nyob ib puag ncig - tias lub plawv dhia tsis zoo lossis zoo li tau tshwm sim. Txog tam sim no, tus kws kho mob yuav tsum tshuaj xyuas ECG cov txiaj ntsig los ua qhov kuaj mob - thaum cov kws tshaj lij tau kawm los nyeem lawv, lawv tsis tuaj yeem ua qhov kev kuaj mob tawm hauv lub tshav pob. Yog tias ECGs uas tau siv los ntawm cov neeg teb thawj zaug muaj kev kuaj mob raug, nws tuaj yeem tso cai kho sai dua. Qhov no yog qhov tseem ceeb tshwj xeeb hauv cov neeg nyob deb nroog, qhov uas nws tuaj yeem siv sijhawm ntau dua ib teev kom tau txais tus neeg mob uas tsis tuaj yeem them lub dav hlau caij tsheb mus rau tom tsev kho mob. Cov theem tom ntej yuav ntxiv cov defibrillator rau lub tshuab ECG nws tus kheej. Tom qab ntawd, thaum nws kuaj pom qhov txawv txav, nws tuaj yeem txiav txim siab qhov tsim nyog rau qhov poob siab thiab - muab tias cov ntaub qhwv poob siab tau muab tso rau - tuaj yeem sim ua kom tus neeg mob rov qab los rau hauv qhov ntswg. Qhov no yuav muaj txiaj ntsig hauv tsev kho mob, uas cov neeg mob twb tau txuas rau ntau lub tshuab thiab yog tias tsis muaj cov kws kho mob txaus los kho tam sim, tag nrho hauv ib lub tshuab lub plawv tuaj yeem saib xyuas nws, txuag lub sijhawm muaj txiaj ntsig xav tau los cawm txoj sia.

Kauj Ruam 6: Xaus

Hauv txoj haujlwm no, ib qho kev ntsuas ECG tau ua tiav thiab tom qab ntawd simulate siv LTSpice. Nws suav nrog cov cuab yeej ntsuas suab nrov, lub lim qis dhau, thiab lub suab tsis hloov pauv kom pom lub teeb liab. Qhov kev sim qhia pom tias tag nrho peb lub Cheebtsam ua haujlwm ib tus zuj zus thiab ua ke thaum ua ke rau tag nrho cov kev sib txuas ua ke. Cov amplifiers txhua tus tau nce ntawm 50, qhov tseeb tau lees paub los ntawm kev sim sim khiav ntawm LTSpice. Cov lim qis dhau tau txiav tawm zaus ntawm 50 Hz, txhawm rau txo suab nrov los ntawm cov kab hluav taws xob thiab cov khoom cuav los ntawm daim tawv nqaij thiab txav mus los. Thaum qhov no yog qhov me me ECG Circuit, muaj ntau qhov kev txhim kho uas tuaj yeem ua tau, mus txhua txoj hauv kev los ntawm kev ntxiv lub lim lossis ob, mus txog txhua qhov hauv ib lub tshuab lub plawv uas tuaj yeem siv ECG, nyeem nws, thiab muab kev kho mob tam sim ntawd.

Kauj Ruam 7: Cov neeg ua tim khawv

Cov neeg ua tim khawv

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