Acoustic coupler for acquisition of coronary artery murmurs

Niels Henrik Zimmermann, Samuel Schmidt, John Hansen, Dorte Hammershøi, Henrik Møller

Research output: Contribution to journalConference article in JournalResearchpeer-review

7 Citations (Scopus)

Abstract

The aim of the study was to design and evaluate a coupler/ microphone system for recording weak murmurs from stenoses in the coronar artery. The suggested design is based on the use of a high quality microphone, coupled to the chest through a small air cavity. Since the determination of the exact frequency range of interest related to murmurs is part of the purpose of the study, one of the goals of the design was to achieve a high signal to noise ratio in a broad frequency range. The high cut off frequency of the coupler is determined by the acoustic impedance of the chest and the design of the coupler, while the low frequency behavior was determined by the properties of the microphone, electronic circuits and inadvertent leakages in the acoustical coupling. The requirement for the microphone and pr-amplifier was a low inherent noise level. The setup was used for collection of heart sounds in a clinical trial including 463 patients referred for elective coronary angiography. The preliminary results show, that it was possible to record heart sound in the diastolic period with a sound pressure level approximately 30 dB above the noise floor
of the microphone and recording system in the frequency range from 200-700 Hz. The capability of the sensor to record diastolic heart sound in the relevant frequency range indicates that the sensor is suitable for recording of coronary murmurs.
Original languageEnglish
JournalComputing in Cardiology
Volume38
Pages (from-to)209-212
ISSN0276-6574
Publication statusPublished - 2011
EventComputing in Cardiology, CinC - Hangzhou, China
Duration: 18 Sep 201121 Sep 2011

Conference

ConferenceComputing in Cardiology, CinC
CountryChina
CityHangzhou
Period18/09/201121/09/2011

Fingerprint

Heart Sounds
Microphones
Acoustics
Coronary Vessels
Noise
Acoustic waves
Thorax
Signal-To-Noise Ratio
Coronary Angiography
Electric Impedance
Pathologic Constriction
Arteries
Air
Clinical Trials
Acoustic impedance
Angiography
Sensors
Cutoff frequency
Pressure
Acoustic noise

Cite this

@inproceedings{4e8634d9be004910a24a624fcfd3be04,
title = "Acoustic coupler for acquisition of coronary artery murmurs",
abstract = "The aim of the study was to design and evaluate a coupler/ microphone system for recording weak murmurs from stenoses in the coronar artery. The suggested design is based on the use of a high quality microphone, coupled to the chest through a small air cavity. Since the determination of the exact frequency range of interest related to murmurs is part of the purpose of the study, one of the goals of the design was to achieve a high signal to noise ratio in a broad frequency range. The high cut off frequency of the coupler is determined by the acoustic impedance of the chest and the design of the coupler, while the low frequency behavior was determined by the properties of the microphone, electronic circuits and inadvertent leakages in the acoustical coupling. The requirement for the microphone and pr-amplifier was a low inherent noise level. The setup was used for collection of heart sounds in a clinical trial including 463 patients referred for elective coronary angiography. The preliminary results show, that it was possible to record heart sound in the diastolic period with a sound pressure level approximately 30 dB above the noise floor of the microphone and recording system in the frequency range from 200-700 Hz. The capability of the sensor to record diastolic heart sound in the relevant frequency range indicates that the sensor is suitable for recording of coronary murmurs.",
author = "Zimmermann, {Niels Henrik} and Samuel Schmidt and John Hansen and Dorte Hammersh{\o}i and Henrik M{\o}ller",
year = "2011",
language = "English",
volume = "38",
pages = "209--212",
journal = "Computing in Cardiology",
issn = "0276-6574",
publisher = "I E E E Computer Society",

}

Acoustic coupler for acquisition of coronary artery murmurs. / Zimmermann, Niels Henrik; Schmidt, Samuel; Hansen, John; Hammershøi, Dorte; Møller, Henrik.

In: Computing in Cardiology, Vol. 38, 2011, p. 209-212.

Research output: Contribution to journalConference article in JournalResearchpeer-review

TY - GEN

T1 - Acoustic coupler for acquisition of coronary artery murmurs

AU - Zimmermann, Niels Henrik

AU - Schmidt, Samuel

AU - Hansen, John

AU - Hammershøi, Dorte

AU - Møller, Henrik

PY - 2011

Y1 - 2011

N2 - The aim of the study was to design and evaluate a coupler/ microphone system for recording weak murmurs from stenoses in the coronar artery. The suggested design is based on the use of a high quality microphone, coupled to the chest through a small air cavity. Since the determination of the exact frequency range of interest related to murmurs is part of the purpose of the study, one of the goals of the design was to achieve a high signal to noise ratio in a broad frequency range. The high cut off frequency of the coupler is determined by the acoustic impedance of the chest and the design of the coupler, while the low frequency behavior was determined by the properties of the microphone, electronic circuits and inadvertent leakages in the acoustical coupling. The requirement for the microphone and pr-amplifier was a low inherent noise level. The setup was used for collection of heart sounds in a clinical trial including 463 patients referred for elective coronary angiography. The preliminary results show, that it was possible to record heart sound in the diastolic period with a sound pressure level approximately 30 dB above the noise floor of the microphone and recording system in the frequency range from 200-700 Hz. The capability of the sensor to record diastolic heart sound in the relevant frequency range indicates that the sensor is suitable for recording of coronary murmurs.

AB - The aim of the study was to design and evaluate a coupler/ microphone system for recording weak murmurs from stenoses in the coronar artery. The suggested design is based on the use of a high quality microphone, coupled to the chest through a small air cavity. Since the determination of the exact frequency range of interest related to murmurs is part of the purpose of the study, one of the goals of the design was to achieve a high signal to noise ratio in a broad frequency range. The high cut off frequency of the coupler is determined by the acoustic impedance of the chest and the design of the coupler, while the low frequency behavior was determined by the properties of the microphone, electronic circuits and inadvertent leakages in the acoustical coupling. The requirement for the microphone and pr-amplifier was a low inherent noise level. The setup was used for collection of heart sounds in a clinical trial including 463 patients referred for elective coronary angiography. The preliminary results show, that it was possible to record heart sound in the diastolic period with a sound pressure level approximately 30 dB above the noise floor of the microphone and recording system in the frequency range from 200-700 Hz. The capability of the sensor to record diastolic heart sound in the relevant frequency range indicates that the sensor is suitable for recording of coronary murmurs.

M3 - Conference article in Journal

VL - 38

SP - 209

EP - 212

JO - Computing in Cardiology

JF - Computing in Cardiology

SN - 0276-6574

ER -