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At least 1,045 records · Page 58Linked to original sources
PubMed1997

Aortic valve replacement in patients 80 years of age and older: survival and cause of death based on 1100 cases: collective results from the UK Heart Valve Registry.

BACKGROUND: Aging of the population and advances in preoperative and postoperative care are reflected in an increasing number of patients > or = 80 years of age undergoing aortic valve replacement (AVR) in the United Kingdom. The present study presents data on postoperative 30-day mortality, actuarial survival, and cause of death based on a large collective patient population. METHODS AND RESULTS: Data were extracted from the UK Heart Valve Registry. From January 1986 to December 1995, 1100 patients > or = 80 years of age underwent AVR and were reported to the registry. Six hundred eleven patients (55.5%) were women. The mean follow-up time was 38.9 months. The 30-day mortality was 6.6%. Of the 73 early deaths, 42 were due to cardiac reasons. The actuarial survival was 89%, 79.3%, 68.7%, and 45.8% at 1, 3, 5, and 8 years, respectively. After the first 30 postoperative days, 144 of the 205 deaths were due to noncardiac reasons. Malignancy, stroke, and pneumonia were the most common causes of late death. Bioprosthetic valves were implanted in 969 patients (88%) and mechanical valves in 131 (12%) patients. There was no difference in early mortality and actuarial survival between the two groups (P>.05). CONCLUSIONS: The above results suggest that under the selection criteria for AVR currently applied in the United Kingdom, patients > or = 80 years of age show a satisfactory early postoperative outcome and moderate medium-term survival benefit.

Aged↗
PubMed1985

Huge left atrial thrombus and valve degeneration in a patient with a bioprosthetic, porcine, mitral valve.

A 43 year old man with a Hancock porcine bioprosthetic valve in the mitral position developed a huge thrombus filling the entire left atrium and chronic degeneration of the bioprosthetic mitral valve. The effective valve orifice was less than 2 mm. These severe findings leading to the patient's death remained undetected while he was alive. This case illustrates the great need for a serial phonoechocardiographic studies in all patients with prosthetic valves.

Adult↗
PubMed1993

Ball-valve thrombus obstructing a bioprosthetic mitral valve.

We present a patient with a large, left atrial ball valve thrombus that was intermittently obstructing a bioprosthetic mitral valve. The diagnosis was confirmed by transesophageal two-dimensional echocardiogram. The transthoracic study initially had failed to demonstrate the true ball valve nature of the thrombus and instead, suggested two separate mass lesions, one in the left atrium and one in the bioprosthetic mitral valve.

Aged↗
PubMed1976

Closure of a ventricular septal defect through the aortic valve: a note of caution regarding resultant narrowing of the aortic valve annulus.

Closure of ventricular septal defects through the aortic valve annulus has been described for a variety of cardiac anomalies. This technique is most appropriate when simultaneous aortic valve replacement is anticipated. A continuous suture through the patch material may produce a purse-string effect upon the aortic valve annulus. The appropriate size of the aortic valve prosthesis should be determined after the closure of the ventricular septal defect is completed to avoid selecting one which may be too large.

Adult↗
PubMed2006

Genomic expression patterns of mitral valve tissues from dogs with degenerative mitral valve disease.

OBJECTIVE: To evaluate global genome expression patterns of mitral valve tissues from dogs with degenerative mitral valve disease (DMVD). SAMPLE POPULATION: Anterior mitral valve leaflets of 4 dogs with severe DMVD and 4 healthy control dogs. PROCEDURES: Transcriptional activities of 23,851 canine DNA sequences were determined by use of an oligonucleotide microarray. Genome expression patterns of tissue from dogs with DMVD were evaluated by measuring the relative amount of complementary RNA hybridization to the microarray probes and by comparing it with gene expression from healthy control dogs. RESULTS: 229 transcripts were differentially expressed (>or= 2-fold change). In dogs with DMVD, expression of 159 transcripts was upregulated and expression of 70 transcripts was downregulated. Of the 229 transcripts, 152 genes could be specifically identified. These genes were grouped into 1 of 9 categories on the basis of their primary physiologic function. Grouping revealed that pathways involving cell signaling, inflammation, extracellular matrix, immune function, cell defense, and metabolism were generally upregulated. Inflammatory cytokines and the serotonin-transforming growth factor-beta pathway were identified as contributory to the pathophysiologic aspects of DMVD. CONCLUSIONS AND CLINICAL RELEVANCE: Evaluation of global expression patterns provides a molecular portrait of mitral valve disease, yields insight into the pathophysiologic aspects of DMVD, and identifies intriguing genes and pathways for further study.

Animals↗
PubMed1977

Clinical and haemodynamic results following mitral valve replacement with the new Lillehei-Kaster pivoting disc valve prosthesis.

Thirty-four patients were re-examined 12-24 months after mitral valve replacement with the Lillehei-Kaster pivoting disc valve prosthesis. There was an improvement of the kinetics with a significant decrease in arteriovenous oxygen difference compared with oxygen consumption. Cardiac output and stroke volume remained abnormally low, not differing significantly from pre-operative values. Resting pulmonary wedge pressure, pulmonary arterial pressure and pulmonary vascular resistance decreased significantly after operation. Mean values for these parameters remained slightly above normal. Exercise produced a rise in pulmonary wedge pressure, which could be explained partly by a simultaneous deterioration of the left ventricular function, as indicated by high end-diastolic pressures, and partly by a degree of obstruction to the foreward flow at the mitral valve itself. The rise in pulmonary wedge pressures led in turn to increased pulmonary arterial pressure, the latter being aggravated in some patients by a rise in pulmonary vascular resistance. Cardiac output increased during exercise, but usually to a lesser extent than was anticipated from the increase in oxygen consumption. The changes in cardiac output during exercise were due to an increase in heart rate, while stroke volume remained unchanged. The mean diastolic pressure difference across the prosthesis was 8.6 mmHg at rest and 12.7 mmHg during exercise. Subjective improvement and reduction in heart volume, as noted in the present series, corroborated the benificial effect of the operative procedure. The valve were all competent, as judged by cinéangiography, except in a few patients, in whom a small valvular or paravalvular leakage was seen. No thrombo-embolic episodes were recorded during the follow-up period.

Adult↗
PubMed2006

Tearing of the mitral valve during vent removal after a successful mitral valve repair: a beneficial role of transesophageal echocardiography.

In this case, a successful mitral valve repair was confirmed by transesophageal echocardiography (TEE) at the end of a cardiopulmonary bypass. The left ventricular vent was placed through the mitral valve to remove the air after the TEE examination, and on its way out, the left ventricular vent damaged the anterior mitral leaflet (AML). Re-examination of the valve with TEE detected the new mitral valve insufficiency. The CPB was reinstituted, and tearing of the lateral third part of the anterior mitral leaflet was found. This case emphasizes the importance of TEE in the operating room as a continuous monitor, not only to evaluate the result of the cardiac surgery, but also to detect any unpredictable events during the surgery.

Cardiopulmonary Bypass↗
PubMed1999

[Ventricular fibrillation as a symptom of prosthetic valve dysfunction that was caused by thrombosis on mitral valve. Surgery or thrombolytic treatment?].

We discuss the case of 49 years old woman with recurrent thrombosis of prosthetic mitral valve with ventricular fibrillation as the complication. For the first time thrombotic prosthetic valve Carbo Medics 33 had been removed and the new valve--Medtronic Hall 31 mm was implanted in the mitral position. After diagnosis of the repeated thrombosis on the replaced prosthetic valve, the patient refused the subsequent operation. The fully effective thrombolytic therapy was then performed. The patient was discharged from the Department and was asymptomatic 4 month follow-up.

Coronary Thrombosis↗
PubMed1992

[Reconstruction of the subvalvular mitral valve tissue in mechanical mitral valve replacement].

Since it was demonstrated in experimental studies that preservation of the subvalvular mitral apparatus is of significance for left ventricular function, it was concluded that in mitral valve replacement complete excision of the mitral valve is disadvantageous for the patient. Clinical experience showed that in patients with mitral regurgitation and large mitral annulus, most of the valvular apparatus can be preserved. In stenotic mitral valve disease, it may be possible to decalcify and mobilize the mitral apparatus and to preserve it. If it is necessary to excise the mitral valve completely, one should think of replacing the chordae tendineae and thus improving postoperative left ventricular function.

Adult↗
PubMed2005

Progression of aortic valve sclerosis and aortic valve stenosis: what is the role of statin treatment?

BACKGROUND: It has recently been suggested that statins could slow the progression of aortic stenosis, but this hypothesis has not been validated in large series. Moreover, there is little information about the role of statin treatment in patients with aortic valve sclerosis. METHODS: From our database 1988--2002, we retrospectively identified 1136 consecutive patients with aortic valve sclerosis (peak aortic velocity [Vmax] > 1.5 and < 2 m/s), or mild to moderate aortic stenosis (Vmax 2.0-3.9 m/s) and with > or = 2 echocardiographic studies > or = 6 months apart; 121 (11 %) were treated with statins. As a control group we randomly selected 121 age-gender-matched patients not treated with statins, with similar initial Vmax. RESULTS: The mean follow-up duration was 54+/-34 months in the statin group, and 50+/-33 months in controls (p = 0.35). There were no differences between statin-treated patients and controls with respect to age, gender, and prevalence of hypertension. More patients in the statin group had documented hypercholesterolemia, diabetes, or had proven coronary artery disease. Overall, the rate of change of Vmax was not different between statin-treated patients and controls (0.13+/-0.24 vs 0.14+/-0.19 m/s/year, p = 0.72). However, in the subgroup of patients with aortic valve sclerosis (n = 52, 26 statin-treated, 26 controls), the rate of change of Vmax was significantly lower in statin-treated patients (0.04+/-0.04 vs 0.08+/-0.06 m/s/year, p = 0.007). CONCLUSIONS: The results of our retrospective study show that statins could be beneficial in retarding the progression of valvular aortic sclerosis to aortic stenosis. This suggests that statins retard the progression of aortic valve lesion in its early stage, a finding that may have important implications in the management of this very common disease.

Aged↗
PubMed2006

[Hemiarch replacement and concomitant valve repair for proximal aortic aneurysm accompanying bicuspid aortic valve with mild regurgitation].

A 64-year-old man who had proximal aortic aneurysm and bicuspid aortic valve with mild regurgitation underwent hemiarch replacement and concomitant valve repair under selective cerebral perfusion and deep hypothermic circulatory arrest. Valve repair technique consisted of leaflet plication according to Schaefers and subcommissural annular plication. No homologous transfusion was required, and the patient was extubated 5.5 hours after surgery. The repaired valve showed trivial regurgitation and no stenosis, and remained stable 22 months after surgery. Schaefers' technique of aortic leaflet plication is simple and reproducible, and is therefore recommendable for such cases.

Aortic Aneurysm, Thoracic↗
PubMed1991

Static and dynamic stresses during valve closure of a bileaflet mechanical heart valve prosthesis.

The effect of contact geometry and component compliance on the magnitude, distribution, and state of various types of stresses on a bileaflet mechanical heart valve prosthesis during valve closure was analyzed using an Edwards-Duromedics mitral valve as example. Static and dynamic stresses developing on both the leaflet and pivot ball during valve closure were modeled using finite element analysis (FEA). Uniform contact between the leaflet and housing as well as between the pivot ball and pivot slot can significantly reduce both static and dynamic stresses around the contact area. The level of the dynamic flexural stresses can be an order of magnitude higher than that of the static stresses. When both the radial and axial compliance of the housing are taken into consideration, peak dynamic stress was more than 40% less than that generated through the impact between a moving leaflet and a non-compliant rigid housing.

Compliance↗
PubMed1991

[Replacement of the ascending aorta and aortic valve with a composite graft using a reversed St. Jude medical mitral valve prosthesis].

Between 1981 and 1989, ten patients underwent replacement of the ascending aorta and aortic valve by a composite graft for an aneurysm of the ascending aorta with aortic regurgitation. The first two cases using an SJM aortic valve prosthesis and Teflon felt-pledgeted mattress sutures for the proximal anastomoses required a coronary bypass graft from the tube graft to the anterior descending coronary artery because of difficulty in completing the graft-left coronary ostial anastomoses. In the subsequent seven cases, an SJM mitral valve prosthesis with a large, soft cuff for a valved conduit was sewn in reverse and a thin wall Teflon roll was used for the Teflon felt of the pledgeted mattress suture in the proximal anastomoses. As a result, anastomoses between the tube graft and coronary ostia were performed easily and successfully in eight patients. One case with Marfan syndrome required reoperation nine years after the first operation for recurrence of the aneurysm of the aortic arch. Thus, the need for careful and continued follow-up is important in the Marfan syndrome.

Aortic Aneurysm↗
PubMed1991

[Thrombosis of mechanical heart valve prosthesis. Value of transesophageal echocardiography in the study of mitral valve prosthesis].

Forty-three consecutive patients with mechanical valve prostheses underwent transthoracic and transoesophageal echocardiography for suspected thrombolic prosthetic valve dysfunction. The results of these investigations were compared with those of cineradiography and the clinical outcome. The diagnosis of thrombosis was retained in 11 of the 43 patients (10 mitral and 1 aortic valve prostheses). The transthoracic Doppler echo was clearly abnormal in 6 of the 11 cases. Transoesophageal echo was of essential value in all cases but one, showing abnormal movement of the mobile element and/or a paraprosthetic thrombus. The cineradiography gave false negative results in 6 cases. In conclusion, these cases underline the undeniable value of transoesophageal echocardiography in occlusive or non-occlusive thrombosis of a mitral valve prosthesis. This investigation should be undertaken whenever there is the least suspicion of thrombosis of the prosthesis.

Adult↗
PubMed1988

In vitro comparison of aortic heart valve prostheses. Part 1: Mechanical valves.

The hydrodynamic performance of a series of mechanical heart valve prostheses is measured in the aortic position. All experiments are performed in an electrohydraulic, computer-controlled pulse duplicator simulating the left side of the human circulatory system. Testing conditions are set according to a Food and Drug Administration interlaboratory comparison protocol with cardiac outputs of 3.0, 4.5, 6.5, and 8.0 L/min at a constant heart rate of 70 beats/min. Mean systolic pressure differences, volume losses, and energy losses, as well as dimensionless pressure losses and energy loss coefficients, are calculated from the recorded pressure, volume, and flow tracings. The results of 10 mechanical heart valve prostheses (eight tilting disc valves and two bileaflet valves) are presented and their clinical relevance is discussed.

Aortic Valve↗
PubMed1986

[Doppler echocardiography determination of the pressure gradient and valve orifice area in mitral valve stenosis].

Pressure gradient and orifice area of stenosed mitral valves can be determined with Doppler echocardiography using the modified Bernoulli equation and the pressure half-time method, respectively (Figures 1 and 2). There was a close linear correlation between Doppler-echocardiographically determined pressure gradients and valve orifice areas with those obtained by invasive methods. In this study, in 85 patients with mitral stenosis of various severity, the valve orifice areas, as derived by the two methods respectively, correlated well (y = 0.89x + 0.15) with a correlation coefficient r = 0.96 and standard error of the estimate SEE = 0.12 cm2 (Figure 3). The correlation was not influenced by the prevailing cardiac rhythm, ventricular function, left ventricular mass or coexistent mitral or aortic regurgitation (Table 1). Accordingly, the Doppler echocardiographic method also appears applicable in the presence of concomitant mitral and aortic regurgitation which precludes an exact determination of valve orifice area with invasive methods. The Doppler echocardiographic method is currently so well validated that it can be regarded as a reliable noninvasive procedure for determination of the severity of mitral stenosis.

Blood Flow Velocity↗
PubMed1995

[The effect of mitral valve repair and postoperative mitral valve function].

Thirty-six patients who underwent mitral valve repair were analyzed to evaluate the effect of mitral valve reconstructive technique. The final aim of this technique is to true up the coaptation line of both leaflets. Resection and reconstruction of the leaflet was performed on anterior leaflet in 11, on posterior leaflet in 12, and on both leaflets in 5. The newly contrived wrapping and shortening chordoplasty was performed on anterior leaflet in 6, on posterior leaflet in 3, and on both leaflets in 2. Two patients had replacement of artificial chordae tendinae with EPTFE suture. Commissuroplasty was performed at anterolateral commissure in 5, at posteromedian commissure in 15, and at both commissures in 5. Thirty patients with dilated annulus underwent ring annuloplasty with Carpentier ring. LVEDVI and LVESVI significantly decreased after mitral valve repair, and left ventricular volume overload was markedly reduced. Mitral valve orifice area was 3.23 +/- 1.14 cm2 and did not show the sign of mitral stenosis after repair. Left ventricular pressure volume area, which reflects the oxygen consumption of the myocardium, was markedly reduced after successful mitral repair.

Adolescent↗
PubMed1994

Results of mitral valve reconstruction in mitral valve insufficiency.

In the last three years forty mitral valve reconstruction (MR) procedures were performed in case of mitral insufficiency (MI). In three cases, anatomical changes made reconstruction impossible for us. One patient had to be re-operated because of unsatisfactory valve function. There was no operative mortality. In twelve of the patients, mitral insufficiency was the only problem, while in twenty eight others additional cardiac procedures (CABG, AVR) were performed. The patients' age ranged from 17 to 77 years. The aortic cross-clamping time for mitral reconstruction without additional cardiac procedures ranged from 35 to 134 minutes. With one exception, the post-operative TEE indicated no, or very little, insufficiency. We concluded that the mitral valve insufficiency can be corrected with very good results and with a very low rate of complications. Such corrections ought therefore be taken into consideration before valve replacement.

Adolescent↗