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PubMed1983

Cardiac valve replacement in patients with active infective endocarditis.

Since the introduction of effective antimicrobial therapy, the leading cause of death in patients with infective endocarditis is no longer sepsis but, rather, congestive heart failure. The mortality is higher in patients with severe heart failure due to infective endocarditis who are treated with medical therapy only than in those who additionally undergo cardiac valve replacement. The mortality is also higher in patients with severe heart failure due to aortic infective endocarditis (40 to 93%) than in those with heart failure due to mitral infective endocarditis (17 to 66%). In patients with and in those without infective endocarditis, surgical intervention can be carried out with comparable mortality not only for aortic valve replacement (9 vs 8.4%) but also overall for valve replacement (10 vs 12%). In patients with class IV heart failure, overall mortality of valve replacement was higher (17%) than in patients with class II (8%) or class III heart failure (7%) and, similarly, comparable with that of matched groups of patients without infective endocarditis. In patients with class IV disability, the mortality of valve replacement was higher in those with active infective endocarditis (19%) than in those with inactive infective endocarditis, possibly due to a higher incidence of sudden onset of severe aortic regurgitation and myocardial abscess. No patient with valve replacement for inactive infective endocarditis developed prosthetic valve endocarditis; a single case of prosthetic valve endocarditis occurred in a patient with active infective endocarditis. In general, early surgical intervention is preferable to procrastination in the management of patients with progressive or severe heart failure due to infective endocarditis. Although, in at least 70% of patients, blood cultures may be rendered sterile within one week of initiation of appropriate antimicrobial therapy, patients with infective endocarditis due to staphylococci, multiply-resistant gram-negative bacilli, fungi, Q-fever or those with myocardial abscess or multiple relapses may require surgical intervention. While the overall incidence of clinically apparent emboli has been reported to be as high as 30%, in a ten-year observation period at the Mayo Clinic, the rate was 5.6%. Patients with echocardiographic evidence of large or mobile vegetations and those with infective endocarditis cause by microorganisms associated with a high risk of embolization such as slow-growing fastidious gram-negative bacilli, fungi (especially Aspergillus) and nutritionally-variant viridans streptococci should be considered candidates for surgery irrespective of a history of emboli.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1984

Clinical and echocardiographic evaluation of the St. Jude cardiac valve prosthesis: follow-up of 126 patients.

One hundred twenty-six patients with a St. Jude valve prosthesis were followed up clinically and studied by combined M-mode echocardiography and phonocardiography. Fifty patients underwent aortic valve replacement, 58 underwent mitral valve replacement and 18 underwent a combination of the two. The early postoperative mortality rate was 8% for aortic, 6.9% for mitral and 6% for combined valve replacement. Follow-up ranged from 2 to 46 months (mean +/- SD 28 +/- 9). The late postoperative mortality rate was 5%; in patients who survived, improvement in New York Heart Association functional class occurred in 97%. Major thromboembolic events occurred in two patients and anticoagulation-related complications occurred in three patients. Valve-related complications occurred in 14 patients and included bacterial endocarditis (6 patients), paravalvular leak (5 patients), severe hemolysis (1 patient), thrombosis of valve (1 patient) and possible mechanical valve failure (1 patient). In 7 of these 14 patients, repeat surgery was required and 5 patients survived. Abnormal echocardiographic findings in these seven patients included a shortened aortic closure (A2) to mitral valve opening interval, increased left atrial and left ventricular size and initial diastolic rounding of the St. Jude valve motion in the patient with the thrombosed valve. It is concluded that the St. Jude valve prosthesis is associated with favorable functional results and a low complication rate for a mean follow-up period of 28 months. Combined M-mode echocardiography and phonocardiography may be useful in assessing patients with suspected complications related to the St. Jude cardiac valve.

Adult↗
PubMed1984

Toxic reactions evoked by glutaraldehyde-fixed pericardium and cardiac valve tissue bioprosthesis.

Bovine pericardial tissue and tissue-derived bioprosthesis fixed in glutaraldehyde and stored in either glutaraldehyde or formaldehyde can induce cytotoxic reactions even after prolonged washing due to the slow leaching of the chemicals used for crosslinking and sterilizing. Sequential rinsing for up to 60 min was still not sufficient to eliminate cytotoxic effects. On the other hand, satisfactory results were obtained when cardiac valves made from glutaraldehyde fixed pericardium were stored in a solution containing 0.02% of propyl-hydroxy-benzoate and 0.18% methyl-hydroxy-benzoate. The valves stored in this solution and rinsed three times for 1 min in normal saline showed few signs of residual cytotoxicity. Rinsing in a solution containing glycine was partially effective in neutralizing the cytotoxic effect, and this or similar approaches offer good possibilities. The use of Chang cells grown in culture provides an excellent quantitative assay for the assessment of residual cytotoxicity and for evaluating the host response to different methods of fixation, storage, and rinsing of tissue derived bioprosthesis.

Aldehydes↗
PubMed2004

Evidence of nanobacterial-like structures in calcified human arteries and cardiac valves.

Mechanisms mediating vascular calcification remain incompletely understood. Nanometer scale objects hypothesized to be a type of bacteria (nanobacteria) are associated with calcified geological specimens, human kidney stones, and psammona bodies in ovarian cancer. Experiments were designed to evaluate human vascular tissue for the presence of similar nanometer-scale objects. Calcified human aneurysms (n = 8), carotid plaques (n = 2), femoral arterial plaques (n = 2), and cardiac valves (n = 2) and noncalcified aneurysms from patients with bicuspid aortic valve disease (n = 2) were collected as surgical waste from the Heart Hospital of Austin, Austin, Texas, and Mayo Clinic, Rochester, Minnesota. Whole mounts or adjacent sections from each specimen were examined by electron microscopy, stained for calcium phosphate, or stained with a commercially available antibody (8D10). Filtered (0.2 microm) homogenates of aneurysms were cultured and costained with 8D10 antibody followed by PicoGreen to detect DNA or incubated with [3H]uridine. Staining for calcium phosphate was heterogeneously distributed within all calcified tissues. Immunological staining with 8D10 was also heterogeneously distributed in areas with and without calcium phosphate. Analysis of areas with positive immunostaining identified spheres ranging in size from 30 to 100 nm with a spectral pattern of calcium and phosphorus (high-energy dispersive spectroscopy). Nanosized particles cultured from calcified but not from noncalcified aneurysms were recognized by a DNA-specific dye and incorporated radiolabeled uridine, and, after decalcification, they appeared via electron microscopy to contain cell walls. Therefore, nanometer-scale particles similar to those described as nanobacteria isolated from geological specimens and human kidney stones can be visualized in and cultured from calcified human cardiovascular tissue.

Aged↗
PubMed2006

A case of Staphylococcus aureus endocarditis after ear piercing in a patient with normal cardiac valve and a questionnaire survey on adverse events of body piercing in college students of Korea.

Body piercing in young adults is on the rise in western countries and also in Korea. It is usually practised by non-medical persons, and therefore frequently entails local adverse events. Serious complications, such as septic arthritis or infective endocarditis, are occasionally reported, but infective endocarditis in patients with normal cardiac valve is rare. We experienced a case of acute S. aureus endocarditis after ear piercing. Thereafter we studied the status and complications of body piercing in college students of Korea based on a questionnaire survey, and revealed that the rate of ear piercing is high (96.5%) and 61.3% of the pierced persons experience local complications.

Adolescent↗
PubMed2001

Detection of fastidious bacteria in cardiac valves in cases of blood culture negative endocarditis.

The diagnosis of blood culture negative endocarditis is still a problem. Fastidious bacteria such as bartonella and coxiella are responsible for cases of blood culture negative endocarditis, the identification of which is mainly based on serological and DNA studies only available in specialised centres. Therefore, a routine technique is needed in surgical pathology laboratories to detect these bacteria in cardiac valve tissue sections. This report describes a staining technique, the Gimenez stain, feasible and sensitive in detecting bartonella and coxiella in two cases of blood culture negative endocarditis.

Adult↗
PubMed1999

Incorporation of liposome-encapsulated amphotericin in artificial/prosthetic cardiac valves for therapy and prevention of fungal endocarditis.

Fungal endocarditis is a highly fatal condition. Fungal prosthetic valve endocarditis is an uncommon but serious infection. Patients require surgery and long-term antifungal therapy. However, recurrence is quite common and eradication of infection is difficult. Liposomal amphotericin is considered to be better than the conventional preparation. It is hypothesized that incorporation of liposome-encapsulated amphotericin inside artificial/prosthetic cardiac valves would result in better tissue concentration of the drug at site of infection and probable prevention of recurrence. The cost of making the same might be considerable but would likely be cost-effective in the long run due to lowered mortality and prevention of recurrence.

Amphotericin B↗
PubMed1995

Cost of diseases in Brazil: breast cancer, enteritis, cardiac valve disease and bronchopneumonia.

The results from the need to develop methodologies for performing cost analysis in developing countries, principally in the region of Latin America, were studied. It, furthermore, serves to generate knowledge from an economic evaluation in order to support decision-making related to the organization of health systems, particularly in the efficient use of resources which are allocated for the provision of medical services. Two chronic diseases (breast cancer and cardiac valve disease) and two infections (enteritis and bronchopneumonia) were selected for the study. The results recommend the use of a valid methodology for economic cost analysis of any disease to be studied and the use of this information in the decision-making process.

Brazil↗
PubMed1992

A physiologic regurgitant cardiac valve phantom for magnetic resonance imaging or color Doppler ultrasound study.

Noninvasive imaging has proven successful in the evaluation of valvular heart disease; primarily with magnetic resonance imaging (MRI) and color Doppler ultrasound (CFM). However, the relationship between the morphology of regurgitant flow in MRI and CFM, as a function of hemodynamic parameters (chamber pressure difference, lesion size, compliance, etc.) is not understood. The goals for this work were: 1) to develop a computer-controlled regurgitant cardiac valve phantom, compatible with artifact-free CFM and MR imaging, 2) to create regurgitant lesions in the phantom which appear similar to those detected clinically, 3) to produce and measure physiologic pressure differences between chambers, compliances, and regurgitant fractions as seen in mild, moderate, and severe regurgitation. Mean chamber pressure differences ranged from 43-142 mmHg over the range of diseases simulated. Similarly, regurgitant flow rates ranged from approximately 0.54-18.6 L/min. Compliance values ranged from 0.83 to 21.95 cc/mmHg. No coherent or incoherent artifacts were observed in MRI or CFM images. Images show a high degree of similarity to regurgitant lesions detected with each modality, confirming that all design goals were met. The system should allow extensive comparative analysis of Doppler ultrasound and MRI flow jets under a wide range of controllable hemodynamic conditions in future experiments.

Aortic Valve Insufficiency↗
PubMed2002

Fibrinogen: intra-individual variability in patients with arterial disease and in patients with cardiac valve replacements.

BACKGROUND: Elevated fibrinogen, considered an independent risk factor for coronary disease, stratifies an individual as high risk for coronary disease. A risk marker requires little intra-individual variability during a long period. OBJECTIVES: To establish intra-individual variability of fibrinogen levels in patients with coronary disease. METHODS: We investigated fibrinogen levels prospectively in four blood samples drawn from 267 patients with a history of arterial disease (arterial group) and from 264 patients with cardiac valve replacements (valvular group). The samples were taken during the course of 78.7 and 78.8 days from the arterial and valvular groups respectively. RESULTS: Marked intra-individual dispersion with a reliability coefficient of 0.541 was found in the arterial group and 0.547 in the valvular group. The Bland-Altman test showed low probability to obtain similar results in different samples from the same individual. These results show large intra-individual variability, with similarities in the arterial as well as in the valvular group. CONCLUSIONS: It is not possible to stratify a patient by a specific fibrinogen dosage.

Analysis of Variance↗
PubMed2001

Fenfluramines, idiopathic pulmonary primary hypertension and cardiac valve disorders: facts and artifacts.

The fenfluramines saga began in 1963 and ended in 1997. Fenfluramines are anorexigenic agents recommended, in April 1996, for the long-term treatment of obesity in USA, before being suddenly withdrawn from the market in September 1997. Over 34 years, about 60 million people were exposed to these drugs worldwide, mainly in Europe. The aim of this critical review is not to attempt to rehabilitate these appetite suppressants but to launch a plea for a more rational and rigorous approach to what might be called objective medical knowledge. Idiopathic primary pulmonary hypertension and cardiac valve disorders which have been both associated with fenfluramines have in common many puzzling features. The metamorphosis of facts into artifacts is only a hypothesis, but seems conceivable from a scientific point of view. Medicine is not only an art, it is also a science, which, like the others, implies adhesion to certain fundamental rules, such as refutation or verification of all experimental results by rigorous and standardized methods, before considering them as established facts. Firstly, a single study, moreover a case-control study like the International Primary Pulmonary Hypertension Study, is not sufficient to establish a causal relationship between exposure to appetite-suppressants and idiopathic pulmonary hypertension, because of the numerous biases which characterize even the best analytical research. Secondly, Doppler-echocardiography cannot be considered as a laboratory test, because of the poor interoperator reproducibility observed in obese patients. The use of this technique in pharmaco-epidemiology implies standardized procedures concerning not only reading data, but also their acquisition, because of possible uncontrolled interactions between sonographers, patients and sophisticated machines. In the case of the fenfluramines saga, numerous methodological artifacts concerning acquisition, processing and interpretation of epidemiologic and echocardiographic data might have contributed to distortion of reality. Let us recall how Webster's dictionary defines artifact: "a spurious observation or result arising from preparatory or investigative procedures or any feature that is not naturally present but is a product of an extrinsic agent, method, or the like".

Appetite Depressants↗
PubMed2003

Upregulation of SR-PSOX/CXCL16 and recruitment of CD8+ T cells in cardiac valves during inflammatory valvular heart disease.

OBJECTIVE: SR-PSOX/CXCL16 is a transmembrane chemokine and is implicated in activated CD8+ T cell trafficking. In the present study, we examined the expression pattern of SR-PSOX/CXCL16 in the heart and investigated a potential role of SR-PSOX/CXCL16 in inflammatory valvular heart disease. METHODS AND RESULTS: Initial expression of SR-PSOX/CXCL16 in murine embryos was detected in endothelial cells lining endocardial cushions in the forming heart at E11.5. From mid-gestation to adult, expression of this gene in the heart was exclusively observed in valvular endothelial cells. Examination of SR-PSOX/CXCL16 expression in human cardiac valves demonstrated that SR-PSOX/CXCL16 was strongly expressed in valvular and neocapillary endothelial cells in patients with infective endocarditis. SR-PSOX/CXCL16 expression in neocapillary endothelial cells was also observed in patients with rheumatic and atherosclerotic valvular disease. Moreover, CD8+ T cells were distributed closely to endothelial cells expressing SR-PSOX/CXCL16. In vitro adhesion assays showed that SR-PSOX/CXCL16 induced adhesion of activated CD8+ T cells to vascular cell adhesion molecule-1 (VCAM-1) through very late antigen-4 (VLA-4) activation. Furthermore, SR-PSOX/CXCL16 stimulated interferon-gamma (IFN-gamma) production by CD8+ T cells. CONCLUSIONS: SR-PSOX/CXCL16 may be involved in CD8+ T cell recruitment through VLA-4 activation and stimulation of IFN-gamma production by CD8+ T cells during inflammatory valvular heart disease.

Animals↗
PubMed2001

[Determination of warfarin in plasma by HPLC and an investigation of monitoring patients after cardiac valve replacement].

OBJECTIVE: A simple HPLC method was established for the determination of warfarin in plasma to investigate the relationship between warfarin concentration and anticoagulant effect. METHODS: The mixture of dichloromethane and hexane (1:9) was used as extracting solvent for the plasma samples. The chromatographic separation was on C18 column with a mobile phase consisting of methanol and 50 mmol/L ammonium acetate buffer (pH2.5, 70:30). RESULTS: The calibration curve was linear within 50-2000 ng/ml. The extraction recoveries of warfarin were 78.0%-81.6%. The recoveries of methodology were 103.1%-106.5%. Inter-day and intra-day RSD were 2.33%-5.46% and 5.29%-7.73%, respectively. This method was used for determining warfarin in 70 patients after cardiac valve replacement. The results showed that 44 cases had their INR within the safety range (1.31-2.35) recommended to Chinese, and of them 37(84.1%) cases had a warfarin level at 616.2 +/- 154.8 ng/ml. CONCLUSION: This method is useful in monitoring warfarin concentration during anticoagulant therapy.

Anticoagulants↗
PubMed1993

In vitro cultivation and immunogenicity of human cardiac valve endothelium.

Endothelial cells were derived from aortic and mitral valves (n = 17) by collagenase digestion and subsequently cultivated in RPMI medium supplemented with 20% fetal calf serum. The cells were stained in an alkaline phosphatase-anti-alkaline phosphatase stain for the expression of MHC Class I and Class II antigens, ICAM-1, ELAM-1, F VIII, and H/Y. The endothelium showed a strong expression of Class I, H/Y, and ICAM-1 molecules, and weak expression of MHC Class II molecules. In contrast to vascular endothelium that is known to express F VIII constitutively, cardiac valve endothelium was found to be negative. F VIII and ELAM-1 were only expressed after stimulation with recombinant interferon-gamma. To analyze the immunogenicity of valve endothelium, cells were used as stimulator cells in a mixed cell culture reaction using lymphocytes as responder cells. Endothelial cells had a 2 to 3 times higher stimulatory effect than peripheral blood lymphocytes. These data allow speculation on whether the observed degeneration of homografts can be reduced if HLA matching is performed prior to valve implantation.

Cell Adhesion Molecules↗