Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “CARDIAC VALVES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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

At least 289 records · Page 16Linked to original sources

[Clinical evaluation of cardiac valve surgery combined with coronary artery bypass grafting].

Between 1991 and 1999, 23 cases underwent cardiac valve surgery concomitant with myocardial revascularization at our institution. Twelve cases (group I) had a primary valvular disease combined with coronary atherosclerosis, and other 11 cases (group II) were due to ischemic mitral insufficiency. There were 2 hospital deaths in group I (17%) and 4 in group II (36%). Three deaths in group II underwent left ventricular volume reduction surgery. On the basis of this observation, we concluded severe mitral regurgitation with ischemic cardiomyopathy was a particularly difficult management problem with disappointing clinical results. On the other hands, we considered concomitant revascularization should be done in the case of primary valvular disease when angiographically significant coronary artery stenosis was present.

Aged↗

Design studies of cardiac valve prostheses.

This paper indicates the vital importance of considering prosthesis articulation in the design of cardiac valves. The prosthesis articulation interrelates with the fixed and the movable prosthetic components. Two basic physiological hemodynamic principles are reviewed: [List: see text] A bileaflet, free-tilting, swivelling prosthesis with a central articular mechanism is undergoing investigation. The four articulations have their own perennial preserving mechanisms to prevent potential failure mode by collecting blood elements in the valve tilting design.

Journal Article↗

[Changes in plasma endothelin in patients undergoing cardiac valve replacement under high dose fentanyl anesthesia].

We measured plasma endothelin (ET) in 11 patients undergoing cardiac valve replacement under high dose fentanyl (116.6 +/- 15.4 micrograms.kg-1, mean +/- SD) anesthesia. Arterial blood samples were obtained: 1) before induction of anesthesia (control), 2) just before the start of cardiopulmonary bypass (CPB), and 3) just before the end of CPB. Endothelin levels were analyzed by radioimmunoassay based on double antibody method using Silica ODS suspension. ET concentrations in period 1, 2, and 3 were 3.0 +/- 1.1, 4.2 +/- 1.7 and 4.5 +/- 1.8 pg.ml-1 (mean +/- SD), respectively. There were no significant differences among these three values (P less than 0.05). The results suggest that under high dose fentanyl anesthesia, surgical stress including that of CPB might not affect ET concentration in plasma.

Aged↗

Endothelialization of cardiac valve bioprostheses.

The main disadvantage of implanted xenograft valves used in cardiac surgery is their poor clinical long-term result, due to early tissue degeneration. In order to improve the performance of such glutaraldehyde fixed bioprostheses, a biological coating with viable endothelial cells was suggested. Therefore, glutaraldehyde preserved bovine pericard patches, as well as commercially available xenograft valves, were lined using human venous endothelial cells or microvascular cells from the subcutaneous fat tissue. Before cells were transplanted into their new environment, grafts were treated with an amino acid solution in order to neutralize the cytotoxic effect of free aldehydes, and precoated with fibronectin-heparin and basic fibroblast growth factor (bFGF) or endothelial cell growth supplement (ECGS) in order to enhance cell proliferation. Coated specimens were kept in culture conditions for a further seven days. Proliferation of transplanted cells was verified by an increase of activation following 3H-thymidine incorporation, while the maintained metabolic cell activity was demonstrated via Prostacycline (PGI2) measurement. Morphology was evaluated by means of scanning electron microscopy (SEM). As evaluated by the beta-Counter, 7 ng/ml bFGF (288,727 +/- 39,668 counts on day 4) substantially enhanced cell proliferation after seeding, opposed to the stimulation with 30,000 ng/ml ECGS (91,924 +/- 1129 counts on day 4), (p < 0.001). The PGI2 release of transplanted cells was stimulated with 25 microM Na arachidonic acid by the factor 2.6 +/- 0.3 and inhibited with 5 mM acetylsalicylic acid by the factor 0.7 +/- 0.2 on day 4 when compared with the basic level.(ABSTRACT TRUNCATED AT 250 WORDS)

6-Ketoprostaglandin F1 alpha↗

Association of cardiac valve calcification and inflammation in patients on hemodialysis.

BACKGROUND/AIMS: This study investigates the possible relationship between inflammation and cardiac valve calcification (VC) in patients on hemodialysis (HD), and identifies risk factors for VC in this patient group. METHODS: Seventy-nine patients on HD (mean age, 52.2 +/- 13.6 years; mean HD duration, 46.8 +/- 34.3 months) were assessed echocardiographically for the presence of VC. Systolic and diastolic blood pressure (BP) values were determined. The blood parameters studied in each case were hemoglobin, blood urea nitrogen, creatinine, calcium, phosphate, calcium-phosphorous (Ca x P) product, albumin, alkaline phosphatase, intact parathyroid hormone, total cholesterol, high-density lipoprotein, low-density lipoprotein, triglyceride, lipoprotein(a), fibrinogen, and C-reactive protein (CRP). The number of patients receiving vitamin D and calcium-containing phosphate binder was determined from records, and presence of diabetes mellitus was noted. RESULTS: Cardiac VC was detected in 36 patients (46%). Five of these patients (6%) had mitral VC, 11 (14%) had aortic VC, and 20 (25%) had calcification of both valves. The patients with VC were significantly older than those without VC (60 +/- 11 vs. 43 +/- 15 years, respectively; P=.001). Compared with the group without VC, the group with calcification had significantly higher systolic (145.1 +/- 14.7 vs. 124.3 +/- 20.7 mmHg, P=.001) and diastolic BP (91.3 +/- 10.3 vs. 75.09 +/- 14.9 mmHg, P=.001); significantly higher phosphate (5.1 +/- 1.4 vs. 4.5 +/- 1.4 mg/dL, P=0.04), CaxP product (48.6 +/- 16.2 vs. 39.8 +/- 11.8, P=.01), lipoprotein(a) [28 (15, 45) vs. 16 (5,42) mg/dL, P=.04], fibrinogen (4.2 +/- 1.2 vs. 3.5-0.9, P=.005), and CRP levels [9 (4, 19) vs. 5 (3, 11) mg/L, P=.05]; and significantly longer HD duration [49 (27, 99) vs. 26 (17, 52) month, P=.01). Apart from age, duration of HD, systolic and diastolic BP, and Ca x P product, VC was associated with CRP (odds ratio, 1.151; P=.007) and fibrinogen (odds ratio, 1.119; P=.005). CONCLUSIONS: The results confirm well-known risk factors for cardiac VC in HD patients, such as older age, longer HD duration, elevated BP, and high Ca x P product. In addition, they suggest that elevated levels of CRP and fibrinogen were associated with VC in the HD population.

Age Factors↗

The haemodynamic effects of dopamine and prenalterol in patients after cardiac valve surgery.

The haemodynamic effects of prenalterol and dopamine were compared in 10 patients about 4 h after cardiac valve replacement during a phase of temporarily depressed myocardial function. The rate of infusion was adjusted to give similar increases in stroke volume with the two drugs (dopamine + 17% and prenalterol + 18%). Both drugs produced marked inotropic and chronotropic effects with significant increases in heart rate, cardiac output, arterial blood pressure, and left and right ventricular stroke work. The arterial blood pressure and the left ventricular stroke work increased significantly more with dopamine than with prenalterol, however. The systemic vascular resistance decreased significantly with prenalterol, whereas it was unchanged with dopamine. The effects of prenalterol could be traced after 90 min, whereas the effects of dopamine vanished within 15 min.

Adrenergic beta-Agonists↗

Cardiac valve replacement in children: a twenty-year series.

Ninety-four children ranging from 3 months to 19 years of age underwent cardiac valve replacement at Columbia Presbyterian Medical Center from 1965 to 1985. The overall operative mortality was 12%, but mortality was higher among patients less than 2 years of age, patients who had had previous cardiac operations, and patients requiring double-valve replacement. Seven of 11 patients who received mechanical valves and no anticoagulation experienced major thromboembolic events. An episode of gastrointestinal hemorrhage that was easily controlled represents the only bleeding complication in the entire series. Valve replacement in children continues to be a high-risk procedure, and efforts to preserve native valve function should be attempted when technically feasible. Our data also suggest that anticoagulation can be safely accomplished in the pediatric age group and should be employed in patients requiring placement of a mechanical prosthesis, especially in the mitral position.

Adolescent↗

Dipyridamole combined with anticoagulant in prevention of early postoperative thromboembolism after cardiac valve replacement.

The preventive effect of 300 mg/day dipyridamole, plus warfarin, on the development of thromboembolism after cardiac valve replacement was evaluated. Study 1 involved 71 patients receiving dipyridamole, 100 mg t.i.d., plus warfarin and resulted in a 2.8% incidence of thromboembolism. Study 2 involved 179 patients and compared the effectiveness of slow release capsules with tablet form dipyridamole at the same dosage, both plus warfarin. No thromboembolic episodes occurred in either group. No serious side-effects of dipyridamole were seen in either study. The results suggest that both slow release and tablet form dipyridamole in combination with warfarin are useful in the postoperative management of heart valve replacement.

Adolescent↗

Echocardiography of cardiac valves in pericardial effusion.

Nine adult patients with large pericardial effusions (PE) demonstrated echocardiographic motion abnormalites of cardiac valves in systole. In four cases (Group 1), the abnormal findings consisted of prominent systolic anterior movements of the mitral valve resembling those seen in idiopathic hypertrophic subaortic stenosis. In Group 2(five cases), typical mitral valve prolapse patterns with large posterior midsystolic displacements well below the C point were observed. Additional abnormalities in Group 2 included tricuspid valve prolapse patterns (four cases), early systolic movement of the aortic valve toward closure (three cases), midsystolic notching of the pulmonary valve (two cases) and abnormal or attenuated motion of the aortic root in all patients. Marked decrease or resolution of PE resulted in complete disappearance of all the observed abnormalities. These findings appeared to be related to large fluid collections behind the left atrium and abnormal movement of the heart in the pericardial space. In the presence of PE, therefore, the echocardiographic observation of abnormal valve motion may not be clinically significant.

Adult↗

[Effects of the magnetic field in magnetic resonance imaging on 15 tested cardiac valve prostheses].

The effects of static magnetic fields used in MR imaging at 0.5 Tesla have been studied on 15 different types of cardiac valves. The displacement of the valves was insignificant at 0.5 Tesla. No significant heating effects was observed with the standard sequences used in cardiac imaging. The image artefacts remain confined to the area immediately surrounding these different valves. It seems possible to perform MRI examinations on patient with the prosthetic heart valves without any risk.

Electromagnetic Fields↗

Pergolide use in Parkinson disease is associated with cardiac valve regurgitation.

OBJECTIVE: To determine if pergolide injures heart valves, by comparing echocardiographic findings in pergolide-treated patients with those of a historical control group. METHODS: Letters were sent to all patients in the authors' practice believed to be taking pergolide, and those responders who wished to continue it were urged to undergo echocardiography. Echocardiograms were obtained on 46 patients, and scores for valvular regurgitation were compared with those from an age-matched control group derived from the Framingham Study. The composite valve regurgitation score was modeled as a linear function of total milligrams lifetime use of pergolide, controlling for age. RESULTS: Eighty-nine percent of pergolide-treated patients had some degree of valvular insufficiency. For each of the three valves for which there are control data, we found an approximately 2- to 3-fold increased risk of abnormal valves in the pergolide patients (odds ratio [OR] approximately 3) and an estimated 14-fold increased risk of concerning tricuspid regurgitation (OR = 18.4). The composite valve score (the sum of valve scores for each of the four valves) was a function of lifetime pergolide use. CONCLUSION: Pergolide may injure cardiac valves, resulting most commonly in tricuspid regurgitation.

Aged↗

Entrapment of leaflet of St. Jude medical cardiac valve prosthesis by miniscule thrombus: report of two cases.

Two patients with dysfunction of the St. Jude Medical cardiac valve prosthesis, one in the aortic and one in the mitral position, are presented. In both, one of the valve leaflets was jammed by a very small thrombus that fixed the leaflet in a semiclosed position. Neither patient received anticoagulation postoperatively. Because of the pathological findings in these 2 patients, anticoagulation for patients with a St. Jude Medical valve prosthesis is recommended for life.

Adult↗

Six years clinical experience with dura mater cardiac valves.

Homologous dura mater bioprostheses have been used for over 6 years in 217 patients who hae undergone cardiac valve replacement at Chulalongkorn Hospital and Medical School, Bangkok. The mitral valves were replaced in 151 patients (69.6%), aortic valve replacements were performed in 29 patients (13.7%), and multiple valve replacement were performed in 37 patients (16.7%). This study will be confined mainly to the isolated mitral and aortic valve replacements. The early deaths in the mitral replacement series was 10.5%, and 13.8% in the aortic valve replacement. Myocardial (pump) failure was the cause of early death in the majority of cases. The late mortality was 7.3% in the mitral position and 12.0% in the aortic position. The mean improvement of NYHA class was from 3.76 to 1.13 in the mitral series, and from 3.64 to 1.32 in the aortic group. The actuarial survival rates at 6 years after operation were 87% and 84% respectively and compare favorably with several prostheses currently in use. There was no case of thromboembolism even though no anticoagulants were used.

Actuarial Analysis↗

Views of cardiac-valve prosthesis patients and their dentists on anticoagulation therapy.

By administering a questionnaire to 253 patients with cardiac-valve prostheses (89.3% responding), and another to 136 of their attending dentists (79% responding), the level of knowledge among both groups of anticoagulant therapy in connection with dental treatment was investigated. The cardiothoracic department monitored all anticoagulation therapies. Of the anticoagulated patients, 96.6% were able to state their medication (94.1% received phenprocoumon); and of 86 dentists with patients on anticoagulation treatment, 94% were aware of their patients' medication. All 20 dentists stating that their patients did not receive anticoagulants were correct. The great majority (98%) of the dentists employed a special measure to reduce the risk of bleeding associated with invasive dental procedures, most commonly (86%) referring patients to their general practitioner or hospital department for adjustment of the anticoagulant therapy. Around 60% of the dentists considered extractions and operations to require measures to reduce the risk of bleeding complications. We recommend referral of patients to the attending physician for adjustment of anticoagulation to a target International Normalized Ratio (INR) of 4.0 or possibly 3.0 before undergoing dental procedures involving the risk of bleeding. Additional reduction of the bleeding risk can be obtained by local application of an inhibitor of fibrinolysis (tranexamic acid).

Adult↗

Cardiac valve replacement and coronary bypass grafts.

A retrospective, six-year survey of 72 patients who underwent combined cardiac valve replacement and coronary artery bypass grafting is presented. The average age was 58 years with a male to female ratio of 3.5:1. Eighteen patients were angina-free, their coronary disease being found by routine coronary arteriography. Fifty-eight patients (81%) had aortic valve replacements, 13 patients (18%) had mitral valve replacements, and one patient had a double valve replacement. Forty-one patients (58%) had a single coronary bypass graft. Total cardiopulmonary bypass times averaged two hours, and the average cold myocardial ischaemic time was 60 minutes. The operative mortality in the group was 8%, which did not differ significantly (chi 2 = 0.25; P greater than 0.6) from the operative mortality of 6% in 1400 operations either for single valve replacement or for isolated coronary grafts which were performed in the same six-year period.

Adult↗

Neonatal Marfan syndrome with congenital arachnodactyly, flexion contractures, and severe cardiac valve insufficiency.

We describe a male neonate with severe arachnodactyly, hypermobility of the fingers, flexion contractures of elbows, wrists, hips, and knees, micrognathia, crumpled ears, rockerbottom feet, loose redundant skin, and ocular abnormalities. Severe cardiac valve insufficiency and aortic dilatation resulted in cardiac failure and death 20 hours after birth. This case represents the severe end of the clinical spectrum of Marfan syndrome. As similar patients have been reported, they may represent a separate mutation.

Contracture↗

Inbred or outbred? An evaluation of the functional allogenicity of farm sheep used in cardiac valve studies.

OBJECTIVE: Cryopreserved allograft cardiovascular tissue elicits a strong cellular and humoral response in recipients; this may accelerate the deterioration of the allograft and complicate future heart transplantation. Juvenile sheep are the standard model for in vivo valve research and have been used to investigate the allogeneic immune response to cardiac valve and vascular tissue transplantation. Studies to date have not considered the extent of allogenicity of sheep used in transplantation studies. METHODS: Functional allogenicity was assessed by standard one-way mixed lymphocyte reaction assay using peripheral blood mononuclear cells. Responder cells were stimulated with irradiated stimulator cells and cultured at 37 degrees C in 95% air and 5% carbon dioxide for 3, 4, 5, and 6 days. Cultures were pulsed with tritiated thymidine for 24 hours and harvested onto filtermats. RESULTS: The allogeneic response, measured as counts per minute, demonstrated a bimodal distribution. Fifty-nine (36.9%) of 160 pairs fell within the first peak (counts per minute < 10,000) and were defined as weak responders. The remaining 101 (63.1%) of 160 pairs of animals demonstrated a strong allogeneic response (counts per minute > or = 10,000) that followed a normal distribution. CONCLUSIONS: More than 1 in 3 pairs of sheep is too closely related to elicit an immune response when cross-reacted. This finding may alter the interpretation of studies that base their findings on allogeneic transplantations in sheep without ascertaining the genetic similarities of the animals. Valve transplantation studies in a sheep model should assess the extent of allogenicity of donor and recipient sheep.

Animals↗

Pregnancy following cardiac valve replacement surgery.

OBJECTIVES: To study the outcome of pregnancy in women with artificial heart valves and to compare the maternal and perinatal outcome in mechanical and bioprosthetic valves. METHOD: Retrospective analysis of 34 pregnancies in 29 women who conceived after cardiac valve replacement was carried out. RESULTS: The majority of women (76.4%) delivered within 5 years of valve replacement. Anticoagulants were administered in 79.4% of pregnancies. Maternal mortality was 2.9% and maternal morbidity in the form of heart failure, atrial fibrillation, valve thrombosis, thromboembolism, bleeding complications and non-functioning prostheses were 2.9%, 5.8%, 2.9%, 2.9%, 11.7% and 2.9%, respectively. The incidence of prematurity was 5.8% and small for gestational age babies was 11.7%. There was no case of abortion. Two babies (5.8%) were still born, one of which had malformations. Maternal complications were significantly higher in women with bioprostheses, though the complications were more grave in the mechanical prostheses group. The perinatal outcome was almost similar in both the groups. CONCLUSION: The perinatal outcome was not different in women with bioprosthetic valves from the ones with mechanical prostheses, but the maternal morbidity was more in women with bioprosthetic valves. Coumarin derivatives were safe and effective and did not lead to embryopathy.

Adult↗