PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “HEART VALVE DISEASES”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources

An intelligent system for diagnosis of the heart valve diseases with wavelet packet neural networks.

In this paper, an intelligent system is presented for interpretation of the Doppler signals of the heart valve diseases based on the pattern recognition. This paper especially deals with combination of the feature extraction and classification from measured Doppler signal waveforms at the heart valve using the Doppler Ultrasound. Because of this, a wavelet packet neural network model developed by us is used. The model consists of two layers: wavelet and multi-layer perceptron. The wavelet layer is used for adaptive feature extraction in the time-frequency domain and is composed of wavelet packet decomposition and wavelet packet entropy. The multi-layer perceptron used for classification is a feed-forward neural network. The performance of the developed system has been evaluated in 215 samples. The test results showed that this system was effective in detecting Doppler heart sounds. The correct classification rate was about 94% for abnormal and normal subjects.

Artificial Intelligence↗

Candida immunity in patients undergoing surgical treatment for heart valve disease.

The appearance of Candida antigen (Latex agglutination method), Candida antibodies (indirect immunofluorescence) and positive fungal cultures as well as the lymphocyte transformation response to Candida antigen "in vitro" was studied in a series of 37 successive patients before and after heart valve replacement. The Candida antigen test was positive preoperatively in 11/36 (31%) and postoperatively in 14/36 (39%) of the patients and in 2/200 (1%) of the controls (blood donors). The differences in the frequencies of positive tests between the patient group and the control group are significant (p less than 0.001). The lymphocyte response to Oidiomycin (Candida albicans) preoperatively was greater than the mean control value in 6/11 (54.5%) of the patients showing a positive Candida antigen test, but only in 4/25 (16.0%) of the patients who were Candida antigen negative. The total number of lymphocytes and the number of ANAE positive (T) cells as well as the lymphocyte response to Oidiomycin (OID), tuberculoprotein (PPD) and phytohaemagglutinin (PHA) decreased markedly postoperatively. Candida antibody titres were positive (greater than or equal to 1:128) in 3/37 (8%) of the postoperative patients and in 2/84 (2.4%) of the controls. This difference is not significant. Positive Candida antibody titres were found postoperatively in 15/37 (41%) of the patients, which is a significantly higher frequency than that seen preoperatively (p less than 0.005). More positive fungal cultures from throat specimens (p less than 0.005) were found in the patient group before surgery than in the control group (hospital personnel). After surgery the number of positive fungal cultures in these cases decreased (p less than 0.001) due to the use of oral antifungal prophylaxis with nystatin tablets.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Kineto- and displacement cardiography in heart valve diseases and possible diagnostic values].

With the help of the method of the kinetocardiography (KKG) inaugurated by Eddleman and the displacement cardiography (DKG) using a high fidelity changer, apart from a control group of 12 test persons with healthy heart 8 different groups of cardiac abnormalities consisting of altogether 88 patients were examined. Displacement cardiography and kinetocardiography did not significantly differ in the course of the curves. The courses of the curves for the cardiac abnormalities proved reproducible. There were significant differences in at least 6 parameters of the curves (p less than 0.05 to p less than 0.001) between the control group and each group with cardiac abnormalities. Linear correlations between the parameters of the curves and invasively gained cardial parameters confirm relations relevant to cardiac abnormalities. In future in possible computer assisted analyses of curves a better rational evaluation in controls of the curves will be the result. The value of this methodology lies in the character of the parameters confirming the cardiac abnormalities. The disadvantage consists in the absent exact quantification of the degree of severity.

Adult↗

[Preoperative coronarography in heart valve disease patients. A probability analysis of coronary lesion].

INTRODUCTION AND OBJECTIVES: The indication of preoperative coronary angiography is routinely performed for patients who are going to valve replacement surgery. The need of coronary angiography is based on age, gender and previous angina, but it is not usually based on risk factors. The purpose of this study has been to find markers to predict the probability of coronary lesion in this group of patients. PATIENTS AND METHODS: We studied retrospectively a population of 541 patients with valvular heart disease who underwent preoperative coronary angiography from 1989 to 1994. Mean age was 61.8 (range 34-82). There were 301 men and 240 women. We analyzed in each patient different variables such as age, gender, previous angina, hypertension, diabetes mellitus, tobacco and familial predisposition. We correlated these variables with the presence of coronary lesion by multivariate analysis. RESULTS: There were 73 patients with coronary lesion greater than 50%. The prevalence of significant coronary artery disease was 13.4%. Angina was present in 34.6%. The risk of coronary lesion was defined as odds ratio: previous angina 3.3; tobacco 2.6; diabetes 2.2; hypertension 1.8 and age 1.4. The others variables were not predictor of coronary lesion. The probability of coronary lesion in patients without those variables (angina, tobacco, diabetes, hypertension) was 4%. If we analyzed age, the probability of coronary lesion was 3% in patients under 65 years and 6% above 65 years. CONCLUSIONS: The lack of previous angina and at least the three risk factors described as predictors of coronary lesion (hypertension, tobacco and diabetes) can define a group of patients with a very low prevalence of coronary lesion, especially if they are under 65 years. It can allow us to avoid preoperatory coronary angiography in patients who undergo valve replacement.

Adult↗

Development of an instrument to measure beliefs and attitudes from heart valve disease patients.

The objective of this study was to verify content validity and reliability of "CAV-Instrument" -- an instrument to measure beliefs and attitudes of heart valve disease patients concerning their illness and treatment. The instrument was analyzed by three judges (using predetermined criteria) and submitted to the pretest (n = 17 subjects). The majority of the items were evaluated as adequate regarding their pertinence, clearness and significance regarding the analyzed questions. The pretest showed the necessity for small changes in some statements, which optimized instrument comprehension by the patients. The restructured instrument was applied to 46 patients to verify internal consistency. The whole instrument and most of its scales presented satisfactory internal consistency. It is concluded that the instrument has content validity and is internally consistent, ratifying the adequacy of its application to measure the strength of association among the researched variables.

Attitude↗

[Are invasive studies advisable in evaluating heart valve diseases?].

The scope of acquired valvular heart diseases has evolved in France during the past 15 years towards a regression of the rheumatoid etiology with emphasis on degenerative and dystrophic diseases. At the same time, the evaluation of valvular diseases has benefited from the considerable advances in isotopic and mostly ultrasonic non-invasive techniques, not to mention more sophisticated techniques such as nuclear magnetic resonance imaging still infrequently used. The different technical variation of sonocardiography, from the TM and bidimensional sonography to transesophageal sonography and continuous and color coded pulsed echo-Doppler, provide reliable answers to the various questions raised before considering a surgical procedure. The remaining role of invasive techniques, such as cardiac catheterization and angiocardiography, considered as the "gold standard" until recently, and reviewed for each valvular disease whether isolated or combined, is becoming more and more restricted. Only coronary angiography remaining the undisputed and absolutely necessary test in case of angina, complications of myocardial infarction, risk or age factors.

Angiocardiography↗

Platelet dysfunction detected at high shear in patients with heart valve disease.

Whether patients with valvular heart disease have a defect of platelet function has been unclear. Despite evidence that these individuals have an abnormality detectable only under conditions of high shear stress, no methods have been widely available to adequately assess platelet function under such conditions. The Platelet Function Analyzer (PFA)-100 measures platelet function in a high shear environment and is well suited to the detection of platelet dysfunction in the clinical laboratory. The instrument records the time for platelets to occlude a membrane coated with collagen and either epinephrine (CEPI) or ADP (CADP). We studied the PFA-100 in 398 patients before open heart surgery; 308 for coronary artery bypass grafting (CABG) and 90 for aortic or mitral valve replacement (VR). Patients were classified as normal (CEPI < or = 153 s); 'aspirin effect' (CEPI > 153 s but CADP < or = 109 s) or abnormal (CEPI > 153 s and CADP > 109 s). In the CABG group, 41.2% were classified as normal, 43.2% as 'aspirin effect' and 15.6% as abnormal. In contrast, in patients undergoing VR, these values were 6.7, 11.1 and 82.4%, respectively. Patients with valvular disease had significantly longer closure times for both CEPI and CADP tests (P < 0.001). In addition, the valvular disease group had a significantly higher proportion of patients with markedly prolonged (> 150 s) closure times in the CADP cartridge (43.3 vs. 3.6%, respectively). Only one (0.3%) patient in the CABG group had non-closure (> 300 s) in the CADP test compared to seven (7.8%) in the valvular disease group. Three of six patients in the latter group bled excessively during surgery. We conclude that abnormal CADP closure is much more frequent among patients with aortic or mitral valve disease compared to those with coronary artery disease. This may reflect pre-existing high-shear damage to platelets that renders them refractory to subsequent shear activation and aggregation in the PFA-100 system. Further studies are needed to more precisely define the platelet defect in these patients. Markedly prolonged CADP closure in patients with valvular disease may indicate an increased likelihood of intra-operative bleeding, although an appropriately designed prospective study is needed to adequately address this hypothesis.

Adenosine Diphosphate↗

[Clinico-diagnostic criteria for the evaluation of social aspects in acquired heart valve diseases].

In spite of the retrogression of the acute rheumatic fever the acquired valvular defects still play an essential role for the morbidity and mortality above all for the younger and middle decenniums of life. In the preliminary diagnostics it is the task of the family doctor to diagnose the valvular defect, to differentiate it from non-organic findings and to estimate its degree of severity. The diagnosis of a carditis renders special difficulties, particularly in its chronic recurrent form. Certain situations of life do not demand only an actual analysis of the findings, but also an individual prognostic estimation. For the choice of profession, the ability for military service and driving a car general references and regularities must be taken into consideration. The indication to operation of the valvular defect is generally given in degree of severity and with restriction also in stage IV. A mitral stenosis is operated already in stage II, when stronger complaints and haemodynamic changes are present. Patients with degree of severity III and IV should avoid a pregnancy, in stage I and II under common control by the internist and obstetrician the pregnant patient may not have any scruples to carry to full term.

Abortion, Therapeutic↗

Association of antibodies against phospholipids with heart valve disease in systemic lupus erythematosus.

A prospective echocardiographic study was carried out on 132 consecutive patients with systemic lupus erythematosus (SLE) derived from three European university medical centres. The prevalence of valvular lesions in patients with SLE was 22.7% compared with 2.9% in a control group of 68 healthy volunteers. 50 SLE patients had antibodies against phospholipids. The prevalence of valve vegetations (8/50 [16%]) and of mitral regurgitation (19/50 [38%]) was significantly higher among the SLE patients with antiphospholipids than among those without (1 and 10/82 [1.2% and 12%], respectively). During follow-up of the patients with valvular lesions, haemodynamically significant clinical valve disease developed in 6 but surgery was required in only 1; 9 had cerebrovascular occlusions; and 7 died, although no death was due directly to the cardiac involvement. Thus, valvular heart disease, particularly affecting the mitral valve, is common in patients with SLE, and the presence of antibodies against phospholipids is associated with a higher prevalence of valvular abnormalities in these patients.

Adolescent↗