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PubMed1999

The influence of mandibular movements on joint sounds in patients with temporomandibular disorders.

STATEMENT OF PROBLEM: There are discrepancies among researchers concerning the reliability and use of temporomandibular joint sounds. PURPOSE: This study examined the reliability of mandibular movements and sounds and determined the correlation between movements and sounds. MATERIAL AND METHODS: The mandibular movements of 35 subjects diagnosed with temporomandibular disorders were recorded with 2 CCD cameras, and sounds were recorded bilaterally with Panasonic electret condenser microphones in the ear canal. Subjects performed 3 movements, each repeated 5 times. RESULTS: Reliability of maximum movements across the 5 trials was good to excellent, with Intraclass Correlation Coefficients (ICC) between 0.76 and 0.91 for all movements except protrusion. Temporomandibular sound event counts were reliable for most movements, including vertical opening, protrusion, and right and left laterotrusion (ICCs between 0.41 and 0.81). Most subjects produced sound events either in 100% or in none of the trials. Reliability for sound events was better during protrusion (ICCs between 0.56 and 0.81) than vertical opening (ICCs 0.41 to 0.64). Subjects with sound events during vertical opening (followed by closing) were significantly more likely to have sound events during protrusion (followed immediately by vertical opening and closing) (P <.01). CONCLUSION: Temporomandibular sound events are generally reliable and warrant study regarding their use in classifying and diagnosing patients with temporomandibular disorders. Condylar translation, which occurs during both vertical opening and protrusion, appears to have a strong influence on the production of temporomandibular sound events.

Acoustics↗
PubMed2006

Sound as an orientation cue for the pelagic larvae of reef fishes and decapod crustaceans.

The pelagic life history phase of reef fishes and decapod crustaceans is complex, and the evolutionary drivers and ecological consequences of this life history strategy remain largely speculative. There is no doubt, however, that this life history phase is very significant in the demographics of reef populations. Here, we initially discuss the ecology and evolution of the pelagic life histories as a context to our review of the role of acoustics in the latter part of the pelagic phase as the larvae transit back onto a reef. Evidence is reviewed showing that larvae are actively involved in this transition. They are capable swimmers and can locate reefs from hundreds of metres if not kilometres away. Evidence also shows that sound is available as an orientation cue, and that fishes and crustaceans hear sound and orient to sound in a manner that is consistent with their use of sound to guide settlement onto reefs. Comparing particle motion sound strengths in the field (8 x 10(-11) m at 5 km from a reef) with the measured behavioural and electrophysiological threshold of fishes of (3 x 10(-11) m and 10 x 10(-11), respectively) provides evidence that sound may be a useful orientation cue at a range of kilometres rather than hundreds of metres. These threshold levels are for adult fishes and we conclude that better data are needed for larval fishes and crustaceans at the time of settlement. Measurements of field strengths in the region of reefs and threshold levels are suitable for showing that sound could be used; however, field experiments are the only effective tool to demonstrate the actual use of underwater sound for orientation purposes. A diverse series of field experiments including light-trap catches enhanced by replayed reef sound, in situ observations of behaviour and sound-enhanced settlement rate on patch reefs collectively provide a compelling case that sound is used as an orientation and settlement cue for these late larval stages.

Animals↗
PubMed1999

The character and consequences of disturbing sound sensations in retraction type middle ear disease.

OBJECTIVE: Transient sound disturbances are common but neglected symptoms in retraction type middle ear disease (R-MED). The aim of this study was to explore and describe their character, their individual consequences, and their role in the development of tympanic membrane retractions. METHODS: Fifty-three subjects with manifest retractions and experiences of disturbing sound and ear sensations were interviewed. A qualitative method was used for analysis of the transcribed interviews. RESULTS: Two different patterns emerged from the interviews. 1. Too weak sound was the least common and most tolerable disturbance. It occurred in 45% and was eliminated by Valsalva's inflation. 2. Sudden and transient sensations of too loud and piercing sound, and intermittent autophony frequently caused intense and intolerable discomfort, which might in turn cause loss of control of speech and conversation. These types occurred in 74% and 60%, respectively, and were eliminated by evacuating the middle ear, for example by sniffing. Subjects who described too loud sound or intermittent autophony commonly preferred a retracted tympanic membrane position. This may explain why pressure equalization by swallowing, and inflation by Valsalva's manoeuvre often elicited discomfort. CONCLUSIONS: Transient experiences of too loud sound or intermittent autophony may indicate a shift of sound preference towards the sound experienced at negative middle ear pressure, and an unreliable tubal function in the sense that it fails to stay closed to protect the ear from sounds and pressure variations in the nasopharynx. Such experiences of altered sound may trigger evacuation of the middle ear, which eliminates the sound disturbance. It is crucial to identify, interpret, and explain the disturbances correctly in the therapy and prevention of retractions, since habitual evacuation exposes the tympanic membrane to strong negative pressure loads and a subsequent risk of developing retraction.

Adult↗
PubMed1998

Correlation of the characteristics of temporomandibular joint and tooth contact sounds.

In this study tooth contact sounds have been compared with temporomandibular joint (TMJ) sounds elicited during opening and closing movements. One hundred and eight subjects were instructed to open as far as possible and then close with sufficient force to produce a tooth contact sound. At least four cycles from each subject were recorded on tape, The first and last sounds in the recording were the tooth contact sounds, these were identified automatically. The mean duration and rise time of each tooth contact sound was calculated and their standard deviations for each subject were calculated to give a measure of the reproducibility. The number and mean amplitude of TMJ sounds occurring during tooth separation were also calculated for each cycle. Highly significant correlations were found between the number and amplitude of the TMJ sounds within a cycle and the duration and rise time, and particularly their standard deviations. Acoustic quiescence during the open-close cycle was associated with short, reproducible tooth contact sounds characterized by a short rise time. The longest and most variable tooth contact sounds were associated with TMJ sounds in all three phases of the open-close cycle. This supports previous clinical findings associating occlusal interferences with TMJ dysfunction.

Acoustics↗
PubMed1999

Hypersensitivity to sound--questionnaire data, audiometry and classification.

This study included consecutive case histories and audiometry of 100 patients with hypersensitivity to sounds. There are several different conditions with the symptom of hypersensitivity to sounds. Hyperacusis is one of those and is seldom described in the literature. The term hyperacusis is often used synonymously with hypersensitivity to sound. We propose that there is a specific condition that could be termed hyperacusis. Hyperacusis is often elicited by loud sounds or by a number of other traumata or diseases. It is not typical of occupational noise exposure (with the exception of exposure to music). The typical patient is relatively young, the mean age being approximately 10 years less than for a population of patients with tinnitus or noise-induced hearing loss. In addition to hypersensitivity to sound, the patients often suffer from tinnitus (86%). Sounds are frequently painful and exposure to loud sounds worsens the condition for some time. The patients often have headaches. Pure tone audiograms show normal hearing or a slight high tone loss. The uncomfortable loudness level is markedly decreased, mostly less than 90 dB HL. Patients with hyperacusis may also be divided into those hypersensitive to the loudness of sounds with a decreased pure tone uncomfortable loudness level and those hypersensitive to certain specific sounds irrespective of loudness showing relatively high pure tone uncomfortable loudness levels and decreased uncomfortable loudness levels to specific sounds. With a careful history other conditions with the symptom of hypersensitivity to sound can be excluded.

Adolescent↗
PubMed2003

Task-dependent visual coding of sound position in visuospatial neglect patients.

Recent neurophysiological evidence has shown that sound position can be coded in multiple frames of reference in the animal brain (i.e. head-centred, eye-centred, or intermediate head/eye centred). Here, we provide evidence for multiple coding of sound positions in humans, by studying pointing to sounds in 14 right brain-damaged (RBD) patients with or without visual neglect (a visuospatial neurological disturbance typically affecting contralesional space). Patients were asked to indicate the position of free-field sounds, either with a hand-pointing or with a head-turning response. Pointing movements were performed either blindfolded or with eyes open, but no visual feedback was available about sound position or the motor response. All RBD patients showed some impairment in sound localisation, particularly for sounds towards the contralesional side. In addition, task-irrelevant vision was more detrimental for hand-pointing than head-turning responses, only for neglect patients. We propose that this finding reflects visual coding of sound position when the eyes are open, which extends the pathological visuospatial bias of neglect patients to sound localisation. Moreover, the absence of any modulatory effects of ambient vision when head-turning responses were adopted suggests task-dependent visual coding of sound position, in agreement with multiple frames of reference for sound localisation.

Aged↗
PubMed2002

An effective quiescent medium for sound propagating through an inhomogeneous, moving fluid.

The idea of similarity between acoustic fields in a moving fluid and in a certain "effective" quiescent medium, first put forward by Lord Rayleigh, proved very helpful in understanding and modeling sound propagation in an atmosphere with winds and in an ocean with currents, as well as in other applications involving flows with small velocity compared to sound speed. Known as effective sound speed approximation, the idea is routinely utilized in the contexts of the ray theory, normal mode representation of the sound field, and the parabolic approximation. Despite the wide use of the concept of effective sound speed in acoustics of moving media, no theoretical justification of Rayleigh's idea was published that would be independent of the chosen representation of the sound field and uniformly apply to distinct propagation regimes. In this paper, we present such a justification by reducing boundary conditions and a wave equation governing sound fields in the inhomogeneous moving fluid with a slow flow to boundary conditions and a wave equation in a quiescent fluid with effective sound speed and density. The derivation provides insight into validity conditions of the concept of effective quiescent fluid. Introduction of effective density in conjunction with effective sound speed is essential to ensure accurate reproduction of acoustic pressure amplitude in the effective medium. Effective parameters depend on sound speed, flow velocity, and density of the moving fluid as well as on sound propagation direction. Conditions are discussed under which the dependence on the propagation direction can be avoided or relaxed.

Acoustics↗
PubMed1992

Parametric representation of normal breath sounds.

The spectral content of normal tracheal and chest wall breath sounds has been calculated using the fast Fourier transform (FFT) (J. Appl. Physiol. 50: 307-314, 1981). Parameter estimation methods, in particular autoregressive (AR) modeling, are alternative techniques for measuring lung sounds. The outcome of AR modeling of 38 complete breaths picked up simultaneously over the chest walls and tracheae of five normal males was evaluated. The sounds were treated as noise, bounded by a quasi-periodic envelope generated by the cyclic action of breathing, thus causing the sounds to become inherently nonstationary. Normalization of the sounds to their corresponding variance envelopes eliminated the nonstationarity, an important requirement for most signal-processing methods. Subsequently, the AR model order was sought using formal criteria. Orders 6-8 were found to be suitable for normal chest wall sounds, whereas tracheal sounds required at least orders 12-16. Using orders 6 and 12, we compared the prominent spectral features of chest wall and tracheal sounds calculated by AR with those found in the spectra calculated by FFT. The polar representation of the AR roots, calculated from the AR coefficients, showed that normal lung sounds from a group of individuals are characterized by a low variability, suggesting that this method may provide an alternative representation of the sounds. The data presented here show that normal lung sounds, when measured in the frequency domain by either FFT or AR modeling, have a characteristic pattern that is independent of the analysis method.

Adult↗
PubMed2006

Sound localization during homotopic and heterotopic bilateral cooling deactivation of primary and nonprimary auditory cortical areas in the cat.

Although the contributions of primary auditory cortex (AI) to sound localization have been extensively studied in a large number of mammals, little is known of the contributions of nonprimary auditory cortex to sound localization. Therefore the purpose of this study was to examine the contributions of both primary and all the recognized regions of acoustically responsive nonprimary auditory cortex to sound localization during both bilateral and unilateral reversible deactivation. The cats learned to make an orienting response (head movement and approach) to a 100-ms broad-band noise stimulus emitted from a central speaker or one of 12 peripheral sites (located in front of the animal, from left 90 degrees to right 90 degrees , at 15 degrees intervals) along the horizontal plane after attending to a central visual stimulus. Twenty-one cats had one or two bilateral pairs of cryoloops chronically implanted over one of ten regions of auditory cortex. We examined AI [which included the dorsal zone (DZ)], the three other tonotopic fields [anterior auditory field (AAF), posterior auditory field (PAF), ventral posterior auditory field (VPAF)], as well as six nontonotopic regions that included second auditory cortex (AII), the anterior ectosylvian sulcus (AES), the insular (IN) region, the temporal (T) region [which included the ventral auditory field (VAF)], the dorsal posterior ectosylvian (dPE) gyrus [which included the intermediate posterior ectosylvian (iPE) gyrus], and the ventral posterior ectosylvian (vPE) gyrus. In accord with earlier studies, unilateral deactivation of AI/DZ caused sound localization deficits in the contralateral field. Bilateral deactivation of AI/DZ resulted in bilateral sound localization deficits throughout the 180 degrees field examined. Of the three other tonotopically organized fields, only deactivation of PAF resulted in sound localization deficits. These deficits were virtually identical to the unilateral and bilateral deactivation results obtained during AI/DZ deactivation. Of the six nontonotopic regions examined, only deactivation of AES resulted in sound localization deficits in the contralateral hemifield during unilateral deactivation. Although bilateral deactivation of AI/DZ, PAF, or AES resulted in profound sound localization deficits throughout the entire field, the cats were generally able to orient toward the hemifield that contained the acoustic stimulus, but not accurately identify the location of the stimulus. Neither unilateral nor bilateral deactivation of areas AAF, VPAF, AII, IN, T, dPE, nor vPE had any effect on the sound localization task. Finally, bilateral heterotopic deactivations of AI/DZ, PAF, or AES yielded deficits that were as profound as bilateral homotopic cooling of any of these sites. The fact that deactivation of any one region (AI/DZ, PAF, or AES) was sufficient to produce a deficit indicated that normal function of all three regions was necessary for normal sound localization. Neither unilateral nor bilateral deactivation of AI/DZ, PAF, or AES affected the accurate localization of a visual target. The results suggest that hemispheric deactivations contribute independently to sound localization deficits.

Acoustic Stimulation↗
PubMed1990

Effect of bilateral auditory cortex lesions on sound localization in Japanese macaques.

1. The ability of four Japanese macaques (Macaca fuscata) to localize sound was determined after bilateral ablation of auditory cortex. The animals were given two tests: a "midline" test in which they had to discriminate noise bursts presented from a loudspeaker located to the left from identical noise bursts presented from a loudspeaker located to the right of midline, and a "hemifield" test in which both loudspeakers were located in their right hemifield. 2. Both of the tests were administered by the use of two different behavioral tasks: a conditioned-avoidance task in which the animals were trained to make or break contact with a water spout to indicate the location of a sound source, and a two-choice task that required the animals to walk to the source of the sound. 3. The results of both the conditioned-avoidance and the two-choice tasks demonstrated that the animals were able to perform the midline discrimination although their localization acuity was reduced. However, the animals had great difficulty in learning to walk to the source of a sound in spite of the fact that they had received previous sound-localization training in the conditioned-avoidance task. This difficulty suggested that the monkeys no longer associated the sound with a location in space. 4. The results of both the conditioned-avoidance and the two-choice tasks demonstrated that the animals were unable to discriminate the locus of a sound source when both loudspeakers were located in the same hemifield. 5. Bilateral ablation of auditory cortex results in both sensory and perceptual deficits. The presence of sensory deficits is indicated by the decreased acuity in the left-right discrimination and the inability to discriminate between two loudspeakers located in the same hemifield. The deficit in the perception of the locus of sound is indicated by the difficulty in learning to approach the source of a sound, an ability which normal monkeys exhibit without training. 6. There appear to be species' differences in the effect of auditory cortex lesions on sound localization. Although cortical lesions result in a sound-localization deficit in several species of primates and carnivores, they have little or no effect on rats.

Animals↗
PubMed2004

Contribution of head shadow and pinna cues to chronic monaural sound localization.

Monaurally deaf people lack the binaural acoustic difference cues in sound level and timing that are needed to encode sound location in the horizontal plane (azimuth). It has been proposed that these people therefore rely on spectral pinna cues of their normal ear to localize sounds. However, the acoustic head-shadow effect (HSE) might also serve as an azimuth cue, despite its ambiguity when absolute sound levels are unknown. Here, we assess the contribution of either cue in the monaural deaf to two-dimensional (2D) sound localization. In a localization test with randomly interleaved sound levels, we show that all monaurally deaf listeners relied heavily on the HSE, whereas binaural control listeners ignore this cue. However, some monaural listeners responded partly to actual sound-source azimuth, regardless of sound level. We show that these listeners extracted azimuth information from their pinna cues. The better monaural listeners were able to localize azimuth on the basis of spectral cues, the better their ability to also localize sound-source elevation. In a subsequent localization experiment with one fixed sound level, monaural listeners rapidly adopted a strategy on the basis of the HSE. We conclude that monaural spectral cues are not sufficient for adequate 2D sound localization under unfamiliar acoustic conditions. Thus, monaural listeners strongly rely on the ambiguous HSE, which may help them to cope with familiar acoustic environments.

Acoustic Stimulation↗
PubMed2005

Distinct cortical pathways for processing tool versus animal sounds.

Human listeners can effortlessly categorize a wide range of environmental sounds. Whereas categorizing visual object classes (e.g., faces, tools, houses, etc.) preferentially activates different regions of visually sensitive cortex, it is not known whether the auditory system exhibits a similar organization for different types or categories of complex sounds outside of human speech. Using functional magnetic resonance imaging, we show that hearing and correctly or incorrectly categorizing animal vocalizations (as opposed to hand-manipulated tool sounds) preferentially activated middle portions of the left and right superior temporal gyri (mSTG). On average, the vocalization sounds had much greater harmonic and phase-coupling content (acoustically similar to human speech sounds), which may represent some of the signal attributes that preferentially activate the mSTG regions. In contrast, correctly categorized tool sounds (and even animal sounds that were miscategorized as being tool-related sounds) preferentially activated a widespread, predominantly left hemisphere cortical "mirror network." This network directly overlapped substantial portions of motor-related cortices that were independently activated when participants pantomimed tool manipulations with their right (dominant) hand. These data suggest that the recognition processing for some sounds involves a causal reasoning mechanism (a high-level auditory "how" pathway), automatically evoked when attending to hand-manipulated tool sounds, that effectively associates the dynamic motor actions likely to have produced the sound(s).

Acoustic Stimulation↗
PubMed1987

The first heart sound in normal and pathological conditions.

Considerations of the physical basis of cardiac contraction and sound generation explain the mechanism of the first sound. Older theories examining this sound as the result of valve closure or stiffening are refuted. It has been demonstrated that the normal first sound originates in the left ventricle alone and that accelerations and decelerations, "timed" by mitral and aortic valves events, are its cause. Three components have been recognized in the first sound: a occurs when the left ventricular wall and septum have reached a certain tension; b when the aortic valve opens; c when the peak of the aortic pulse has been reached. The ventricular septum is an integral and essential part of the left ventricle. In left bundle branch block, abnormal activation of the septum transforms this into a passive structure resulting in a slower rise of left ventricular pressure and a longer isovolumic period. This causes a small and delayed first sound, whose components, however, are still separated by normal intervals. In right bundle branch block, the first sound has a normal amplitude and its components are separated by normal intervals. If there is a larger late component, it is a c component, similar to that of normal elderly subjects. A larger c component may also be found in atrial septal defect. The cannon sound of AV block is caused by more rapid deceleration due to higher atrial pressure at the onset of ventricular contraction resulting in intense vibrations. The first sound of arrhythmias varies in the different conditions and even in different subjects, due to the effect of several variable factors. Elevated left atrial pressure, stiffening of the mitral valve in mitral stenosis, causes a slow onset and a more rapid rise of LV pressure. This results in a delayed, but larger, first sound. The action of catecholamines on the myocardium dramatically increases the first sound. The latter can be considered as an index of contractility and may be of great interest during stress tests.

Heart↗
PubMed1990

[Masticatory area in the persons who become conscious of temporomandibular joint sound].

Using subjects conscious of temporomandibular joint sound and normal subjects, the ratio of the masticatory area to the mandibular border movement area was measured. Also, splints were fitted to subjects conscious of TMJ sound and changes of sound and masticatory areas were measured. 1. In normal subjects, the ratio tended to vary little with any of the test foods. 2. In subjects conscious of the TMJ sound, the ratio decreased in the case of all test foods when compared with the normal subjects. 3. In subjects conscious of TMJ sound, it was observed that the TMJ sound occurred in some subjects but not in others during mastication. 4. The decrease in the ratio of the subjects with no TMJ sound during mastication was more outstanding than that of subjects in which TMJ sound occurred during mastication. 5. After fitting splints, the change in the TMJ sound was accompanied by a change in the masticatory area. 6. These findings suggest that the decrease in the mastication area experienced by subjects conscious of TMJ sound, when compared with normal subjects, may be caused by the TMJ sound.

Humans↗
PubMed2002

[A new medical education using a lung sound auscultation simulator called "Mr. Lung"].

We developed a lung sound auscultation simulator "Mr. Lung" in 2001. To improve the auscultation skills of lung sounds, we utilized this new device in our educational training facility. From June 2001 to March 2002, we used "Mr. Lung" for our small group training in which one hundred of the fifth year medical students were divided into small groups from which one group was taught every other week. The class consisted of ninety-minute training periods for auscultation of lung sounds. At first, we explained the classification of lung sounds, and then auscultation tests were performed. Namely, students listened to three cases of abnormal or adventitious lung sounds on "Mr. Lung" through their stethoscopes. Next they answered questions corresponding to the portion and quality of the sounds. Then, we explained the correct answers and how to differentiate lung sounds on "Mr. Lung". Additionally, at the beginning and the end of the lecture, five degrees of self-assessment for the auscultation of the lung sounds were performed. The ratio of correct answers for lung sounds were 36.9% for differences between bilateral lung sounds, 52.5% for coarse crackles, 34.1% for fine crackles, 69.2% for wheezes, 62.1% for rhonchi and 22.2% for stridor. Self-assessment scores were significantly higher after the class than before. The ratio of correct lung sound answers was surprisingly low among medical students. We believe repetitive auscultation of the simulator to be extremely helpful for medical education.

Auscultation↗
PubMedDate not supplied

A soundscape study: What kinds of sounds can elderly people affected by dementia recollect?

In this study, the kinds of sounds recollected by elderly people with dementia were investigated as a first step towards improving their sound environment. Onomatopoeias were presented to elderly people as keys to recollecting sounds, and they told what they imagined from each onomatopoeia. The results are summarized as follows. (1) Generally speaking, sounds from nature, such as the songs of birds and the sound of rain were recollected easily from onomatopoeias, regardless of gender. (2) Sounds of kitchen work were recollected by women only. (3) Sounds from old routines were recollected clearly. (4) Sounds that elicited feelings of nostalgia were also recollected intensely from onomatopoeias. These results show that elderly people suffering from dementia are able to recollect the sounds that had once occupied very important parts of their lives. However, these sounds in themselves are not unusual sounds in their daily lives. This suggests the importance of soundscape design in daily life.

Aged↗
PubMedDate not supplied

Third heart sound revisited: a correlation with N-terminal pro brain natriuretic peptide and echocardiography to detect left ventricular dysfunction.

BACKGROUND: Auscultation of the third heart sound is an age-old sign for predicting ventricular dysfunction. New technology and biomarkers like two-dimensional echocardiography and N-terminal pro brain natriuretic peptide, respectively, have sidelined the utility of this sign, which does not involve any cost and is readily accessible. We sought to find the predictive accuracy of third heart sound and its correlation with N-terminal pro brain natriuretic peptide and ejection fraction using two-dimensional echocardiography to detect left ventricular dysfunction in patients of acute coronary syndrome. METHODS AND RESULTS: One hundred and ten patients presenting with acute coronary syndrome [acute ST elevation myocardial infarction (n=74) and non-ST elevation myocardial infarction (n=36)] were prospectively studied. A senior cardiologist, blinded to N-terminal pro brain natriuretic peptide and ejection fraction results auscultated for a left ventricular third heart sound in each patient. Ejection fraction was measured using modified Simpson's technique on two-dimensional echocardiography and N-terminal pro brain natriuretic peptide was measured using electrochemiluminiscence assay. Median levels of N-terminal pro brain natriuretic peptide were used to provide a dichotomous approach for analysis of the data. Third heart sound was present in 40 patients (acute ST elevation myocardial infarction: n=27, non-ST elevation myocardial infarction: n=13) and absent in 70 patients (acute ST elevation myocardial infarction: n=47, non-ST elevation myocardial infarction: n=23). The sensitivity and specificity of third heart sound for predicting N-terminal pro brain natriuretic peptide above median was 65.5% and 92.7%, respectively. The positive and negative predictive value was 90% and 73%, respectively. The N-terminal pro brain natriuretic peptide of those having third heart sound was 4081 +/- 2705 pg/ml compared to 1239.3 +/- 1169 pg/ml in those without third heart sound (p < 0.001). The sensitivity of third heart sound to detect ejection fraction <45% was 67.9% while the specificity was 74.4%. The positive and the negative predictive values were 47.5% and 87.1%, respectively. The ejection fraction of patients having third heart sound was 47.5 +/- 11.3% compared to 56 +/- 10.4% without third heart sound (p < 0.001). CONCLUSIONS: Auscultation of third heart sound has a good specificity and predictive value for predicting elevated N-terminal pro brain natriuretic peptide and left ventricular dysfunction. Thus age-old clinical cardiology still holds its forte in this new era of technology-driven cardiology.

Heart Sounds↗
PubMed1988

[Genesis and clinical significance of the "low-pitched" aortic ejection sound].

The genesis and clinical significance of the aortic ejection sound with a low-frequency predominance and delayed appearance were studied. This is recorded on the phonocardiogram in some patients with left ventricular dysfunction. Subjects studied consisted of 10 patients with a low-pitched ejection sound and seven patients with an ordinary high-pitched aortic ejection sound. No patients had echocardiographic findings suggestive of organic lesions of the aortic valve. Time relationships among the ejection sounds, aortic valve echograms and carotid artery pulses, and then movements of the aortic valve cusps and non-invasively estimated left ventricular systolic function were compared between the two groups. Results were as follows: 1. The low-pitched ejection sound: 1) The beginning of the sound was nearly coincident with the onset of the upstroke of the carotid artery pulse and the initial full opening of the aortic valve cusps. 2) The beginning of the ejection systolic murmur followed immediately after the ejection sound. 3) The amplitude of the sound was closely related to the height of the carotid artery pulse in a case of atrial fibrillation. 2. The low-pitched ejection sound vs the high-pitched ejection sound: 1) The onset of the low-pitched ejection sound was significantly delayed. 2) The amplitude and the velocity of the initial opening of the aortic valve cusps were significantly decreased. 3) The preejection period (PEP) was significantly prolonged; the ejection time (ET) was significantly shortened; and the PEP/ET ratio was significantly increased.(ABSTRACT TRUNCATED AT 250 WORDS)

Aorta↗