Search Results
Results 201 - 250 of 285
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Cozic M - - 1998
The authors describe a cardiac acoustic mapping system designed to acquire, analyse, and display the amplitude distribution of a phonocardiogram (PCG) recorded from 22 sites on the thorax. A new PCG envelope detection approach, implemented by analogue circuits, enables simultaneous sampling of PCG envelopes from the 22 sites at a ...
Voon Wel-Chol - - 1998
Controversies exist about the timing relationship between the fourth heart sound and the ventricular inflow Doppler events. Besides, there has been no data about the timing relationship between the fourth heart sound and the ventricular outflow Doppler events. This study was designed to measure these phono-Doppler timing relationships and to ...
Cichero J A - - 1998
A hypothetical discussion of the cause of swallowing sounds is presented. It is suggested that the pharynx contains a number of valves and pumps that produce reverberations within the pharynx to generate swallowing sounds. As heart sounds are propagated via vibration of muscles and valves, it is further suggested that ...
Marcon Carlo - - 1997
Doppler echocardiographic variables were sought for predicting the third and fourth heart sounds, as documented by phonocardiography. Phonocardiographic recordings of gallop sounds and Doppler echocardiographic investigations of mitral inflow and pulmonary venous flow were evaluated in 85 subjects by discriminant and multiple regression analysis. Of 85 subjects 47% had a ...
Ishikawa M - - 1997
Patients (n = 181) with a myocardial infarction, with (n = 20) or without (n = 161) a clearly audible fourth heart sound detected 1 month after the onset of a myocardial infarction, were followed for 56.2 +/- 21.4 months for cardiac events (death, myocardial infarction, percutaneous transluminal coronary angioplasty, ...
Voon Wen-Chol - - 1997
To investigate the characters of the transmitted transmitral A wave associated with a fourth heart sound, left ventricular inflow, and outflow Doppler echocardiography and phonocardiography were recorded in 13 patients with a fourth heart sound and 9 age-matched control subjects. The Doppler echocardiographic data were compared between both groups and ...
Saijo Y - - 1997
The purpose of this study was to ultrasonically characterize infarcted human myocardial tissue at the microscopic level by scanning acoustic microscopy. Infarcted myocardial specimens from ten cases with acute myocardial infarction were studied. Specimens were formalin fixed, paraffin embedded and sectioned to 10-micron thickness. A specially developed scanning acoustic microscope ...
Ishikawa A A Laboratory of Animal Genetics, School of Agricultural Sciences, Nagoya University, Aichi, - - 1996
Hair growth and skin structure were examined in kinky coat (kc) musk shrews, Suncus murinus. The first hair growth cycle and the development of hair bulbs were normal. Histological characteristics of hair follicles and bulbs were similar in kc/kc and normal +/kc shrews. The mean thickness of epidermis and dermis ...
Thompson P D - - 1996
While the critical task of the preparticipation cardiac examination is identifying life-threatening conditions, care must be taken not to exclude healthy individuals from activity. The vast majority of exams will be negative, but the physician should be alert to such potentially lethal conditions as hypertrophic cardiomyopathy, aortic stenosis, and Marfan ...
Longhini C - - 1996
The third heart sound (S3) is often present in children and adolescents but is not present in most adults. Applying at the left ventricle a mathematical model, the mechanism of the disappearance of S3 was studied employing the frequency analysis of the sound and echocardiographic data. The existence of a ...
Pantalos G M - - 1996
In an attempt to explore methods to reduce total artificial heart (TAH) acceleration and sound production, in vitro measurements of TAH acceleration and sound were made when using a variety of prosthetic valves in a test ventricle. A miniature, uniaxial, high fidelity accelerometer was glued to the housing of a ...
Gonzalez M H - - 1995
Fifty cadaver hands were dissected to better delineate the extensor tendon anatomy to the little finger. The extensor digitorum communis was present in 35. Of 15 hands without an extensor digitorum communis, 12 had a junctura present. Three hands lacked both extensor digitorum communis and juncturae. Transfer of the extensor ...
Candy J V - - 1995
People with serious heart conditions have had their expected life span extended considerably with the development of the prosthetic heart valve especially with the great strides made in valve design. Even though the designs are extremely reliable, the valves are mechanical and operating continuously over a long period; therefore structural ...
Häggström J - - 1995
Auscultatory, phonocardiographic (PCG), radiographic, and echocardiographic evidence of chronic valvular disease (CVD) were studied in 79 Cavalier King Charles Spaniels with a mean age of 7.6 years (SD 2.6). Cardiac murmurs were present in 59 of the dogs and the intensity of the systolic cardiac murmur, assessed by auscultation (grade ...
Baracca E - - 1995
Hypertrophic cardiomyopathy (HCM) is a typical primary cardiac disease characterized by diastolic abnormal function due to both prolonged relaxation and decreased compliance (Sanderson et al., 1977; Spirito & Maron, 1990). Since the contribution of the atrial systole to ventricular filling is usually increased, the appearance of a fourth heart sound ...
Jeffrey W D - - 1995
H.D., the noted writer Hilda Doolittle, wrote three differing accounts of her first analytic session with Freud, held on March 1, 1933. The first account was written on the same day as her session in a letter to her friend Bryher; it indicates that Freud did not meet H. D.'s ...
Kim S H - - 1994
A comparative study was made of the sounds produced by normal prosthetic valves (St. Jude Medical, Bjork-Shiley, polymer) with those produced by the same valves but having simulated thrombosis at the stent, hinge, or strut. Comparisons of the closing sound were made for the power frequency spectra associated with individual ...
Harvey W P - - 1994
Most diagnoses of cardiovascular disease are made in the office or at the bedside. For example, in pulsus alternans of the radial pulse, observed when first greeting a patient, alteration of intensity of the second sound and systolic murmur and a ventricular (S3) gallop are clinical pearls--often subtle--that diagnose cardiac ...
Wood J C - - 1994
To determine whether focal changes in myocardial material properties are important in determining the response of first heart sound acceleration amplitude and frequency to myocardial ischemia, cardiac vibrations were simultaneously recorded from ischemic and nonischemic regions of canine epicardium by use of ultralight acceleration transducers. Cardiac acceleration and hemodynamics were ...
Takeda Y - - 1993
The existence and distribution of melanocytes in the periodontal ligament of the mongrel dog were investigated. Melanocytes were found in the periodontal ligament of the maxillary incisor and premolar segments. Melanocytes in the periodontal ligament varied in number, and generally appeared as dendritic or elongated cells with several, long cytoplasmic ...
Ivanova M - - 1993
We investigated the capacity of porcine sperm-zona binding and penetration by using bioassay to differentiate between spermatozoa from fertile and subfertile boars. Semen was collected from Large White boars grouped into categories of fertile and subfertile (n=5 per each group) according to the results of artificial insemination. Boars in both ...
Akay M - - 1993
In this article, a new approach has been proposed to investigate the extraction of useful information from diastolic heart sounds caused by partially occluded coronary arteries. This method, which estimates and tracks the zeros (poles) of the diastolic heart sounds directly, takes advantage of the FTF/FAEST (Fast Transversal Filters/Fast a ...
Kono T - - 1993
OBJECTIVES: The purpose of this study was to examine the temporal relation between the development of a third heart sound during the course of evolving heart failure and associated hemodynamic abnormalities. BACKGROUND: Although various theories have been proposed to explain the origin of the third heart sound, the exact origin ...
Bulgrin J R - - 1993
Heart sounds provide clinicians with valuable diagnostic and prognostic information. They are repetitive in nature, but reflect complex mechano-acoustical events which have been inadequately described by traditional digital signal processing methods. In this study, left ventricular and aortic intravascular phonocardiograms were obtained from six patients by catheter-mounted piezoelectric transducers. Phonocardiograms ...
Folland E D - - 1992
BACKGROUND: The presence of third heart sounds in patients with valvular heart disease is often regarded as a sign of heart failure, but it may also depend on the type of valvular disease. METHODS: We assessed the prevalence of third heart sounds and the relation between third heart sounds and ...
Akay M - - 1992
Previous studies have indicated that heart sounds may contain information which is useful in the detection of occluded coronary arteries. Specifically, previous work based on analysing heart sounds recorded during the diastolic portion of the cardiac cycle, when blood flow through the coronary arteries is maximum, has shown that additional ...
Akay M - - 1992
This study examines the utility of neural networks for detecting coronary artery disease noninvasively by using the clinical examination variables and extracting useful information from the diastolic heart sounds associated with coronary occlusions. It has been widely reported that coronary stenoses produce sounds due to the turbulent blood flow in ...
McGuirk S M - - 1991
Cardiac diseases of cattle may involve valvular structures, myocardium, pericardium, or blood vessels and are manifested by the clinical signs of cardiac dysrhythmias, cardiac murmurs, generalized edema, muffled heart sounds, jugular venous distention, jugular venous pulsations, pulmonary edema, pleural effusion, or ascites. Digoxin, quinidine, and furosemide can be used effectively ...
Groch M W - - 1991
A method to trigger multigated blood-pool (MGBP) acquisition using both the first and second heart sound has been developed. The heart sound gating (HSG) circuitry identifies, individually, both the first (S1) and second (S2) heart sounds from their timing relationship alone, and provides two trigger points during the cardiac cycle. ...
Lee C H - - 1991
An early diastolic sound in a patient with apical left ventricular disease is reported. Pulsed Doppler echocardiography showed blood flow within the left ventricular cavity during the isovolumic relaxation period whose peak flow velocity was synchronous with the onset of this diastolic sound. Because it occurred before filling started it ...
Akay M - - 1990
Previous studies done by our group suggest that partially occluded coronary arteries may generate sounds due to turbulent blood flow. To support these previous findings the frequency spectra of diastolic heart sounds are compared before and after angioplastic surgery. Since the low-level sounds associated with partially occluded coronary arteries are ...
Ishizuka T - - 1990
According to Adolph et al., valuable information on the nature of myocardium can be obtained through frequency analysis of first heart sounds (S1) during the isometric contraction phase (ICP). We compared dominant frequencies (DF), which were defined as the frequency of maximum sound voltage, of S1 among 37 outpatients undergoing ...
Durand L G - - 1990
A surgical protocol was designed to implant, in seven dogs, a programmable sequential atrioventricular pacemaker after destruction of the bundle of His to produce a chronic heart block. The heart rate and P-R interval were then varied independently and their influence on the spectra and acoustic transmission of the mitral ...
Durand L G - - 1990
The paper describes the effects of neuromuscular blockade, sternotomy and atrio-ventricular pacing, and a two-week recovery period on the spectra and acoustic transmission of mitral M1 and aortic A2 sound components in dogs. Results indicate that neuromuscular blockade does not affect the attenuation properties of the heart/thorax acoustic system even ...
Akay M - - 1990
Previous studies have indicated that diastolic heart sounds may contain information useful in the detection of occluded coronary arteries. In this study, recordings of diastolic heart sound segments were modeled by autoregressive (AR) methods including the adaptive recursive least-square lattice (RLSL) and the gradient lattice predictor (GAL). Application of the ...
Mizutani A R - - 1990
We constructed and tested an inexpensive (less than $50) FM wireless, acoustically shielded, precordial radiostethoscope that enables the anesthetist to follow the heart tones and breath sounds of the patient regardless of the anesthetist's location in the operating room. We compared our acoustically shielded device with a similar, but acoustically ...
de Loos F - - 1989
Bovine cumulus oocyte complexes (COCs) as used for in vitro maturation and fertilization can be classified into different categories by light microscopical inspection. We have distinguished four categories based on compactness and transparency of the cumulus investment and homogeneity and transparency of the ooplasm. The four categories were studied for ...
Mukerji B - - 1989
Athletic training commonly increases left ventricular and diastolic volume and left ventricular wall thickness within weeks to months of the beginning of vigorous conditioning. Bradycardia is usual and a third heart sound is frequently audible. A systolic heart murmur is present in 30 to 50 percent of athletes. An increased ...
Vancheri F - - 1989
To investigate the relation between changes in left ventricular inflow velocity and the timing of third and fourth heart sounds, simultaneous phonocardiograms and continuous wave Doppler traces were recorded in 48 patients (aged 17-78) with heart disease and in 21 normal children. The onset of the first vibration of the ...
Thulin L I - - 1989
Most currently used mechanical heart valve prostheses generate a distinct sound when they close. This sound is sometimes disturbing to the patient, and may impair quality of life. In a study of 285 patients followed up for a mean of 2.5 years after mechanical heart valve replacement, one-third were sometimes ...
Koiwa Y - - 1988
Several investigators have aimed to clarify the patient's left ventricular (LV) physical properties by free vibration analysis of heart sound. Recently we have developed a transfer function (TF) method to calculate the LV viscoelasticity. To clarify whether this TF method and a clinical first heart sound (1 HS) analysis are ...
Jordan M D - - 1987
To determine the meaning of an audible fourth heart sound (S4), 51 subjects (21 normal and 30 abnormal persons), aged between 38 and 74 years (mean, 55.4 years), were examined by nine "blinded" physicians (four cardiologists, five house staff officers). Audibility scores were compared with phonocardiographic, echocardiographic, and hemodynamic measurements. ...
Shaver J A - - 1986
The salient phonoechocardiographic features of patients having hypertrophic cardiomyopathy (HCM) with or without left ventricular outflow tract (LVOT) gradients are reviewed. Intracardiac sound and pressure recordings from high fidelity catheter-tipped micromanometers have documented that the precordial murmur is the summation of both the systolic ejection murmur (SEM) arising from the ...
Ionescu V - - 1986
The morphologic analysis of the second heart sound may provide some useful informations, not enough debated in the literature, concerning the functional status of cardiac patients. We noticed significant temporal discrepancies on the phonocardiographic tracings between the onset of the second heart sound in the lowest and in the highest ...
Blatchford J W JW - - 1985
The first successful suture of a wound of the heart was performed by Ludwig Rehn in 1896. This landmark operation--set against a background of widespread doubt with regard to its possibility and censure of its very contemplation--reversed the prevailing belief in the inviolability of the heart. It marks the beginning ...
Greenwood R D - - 1985
The physical examination requires careful palpation of pulses and measurement of blood pressure, evaluation of heart sounds (including detection of the third heart sound) and appreciation of clicks and murmurs. Combined with the chest x-ray and electrocardiographic findings, these steps usually lead to the most common diagnoses: innocent murmur; left-to-right ...
Farrar M W - - 1985
A 72 year old woman was thought to have a paradoxically split second heart sound. Echocardiography with simultaneous phonocardiography revealed a late systolic click resulting from isolated tricuspid valve prolapse. Respiratory variation of the click in relation to the second heart sound resulted in an auscultatory phenomenon simulating paradoxical splitting ...
Smith D - - 1985
Maximal negative left ventricular dP/dt is widely used as a measure of isovolumic muscular relaxation of the left ventricle. In the course of canine experiments designed to elucidate the hemodynamic events responsible for the aortic component of the second heart sound, high-fidelity left ventricular pressure and dP/dt signals were recorded ...
Gershlick A H - - 1984
The interrelation between the loudness of the first heart sound, the time interval from the Q wave to the onset of the first heart sound (QM1), and the mitral valve closure rate was studied in nine patients presenting with left atrial myxomata. In seven patients the first heart sound was ...
Humen D P - - 1984
The findings in four patients with marked paradoxical septal motion and an unusual early diastolic sound are presented. Each patient had markedly abnormal right ventricular function. Phonocardiograms, apexcardiograms, and echocardiograms showed the sound to precede the expected timing of a third heart sound and to coincide with the peak leftward ...
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