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At least 1,747 records · Page 97Linked to original sources
PubMed2005

Redo mitral valve replacement in children.

BACKGROUND: Despite excellent results with current techniques of mitral valve repair, some children still require mitral valve replacement (MVR). Of necessity, a certain percentage of these children need valve rereplacement (redo MVR). METHODS: Of 82 MVRs at our institution since 1988, 22 were redo MVRs in 21 children aged 1.4-21 years (mean 9.8 +/- 5.6 years). Interval from initial MVR was 1 month to 18 years (mean 5.8 +/- 4.9 years). Reoperation indication was primarily stenosis in 13 (usually pannus formation), regurgitation in 4, valve thrombosis or embolism in 4, and endocarditis in 1. The initial valve was mechanical in 18 and xenograft in 4. RESULTS: During redo MVR, 8 of 22 (36%) patients had additional procedures including left ventricular outflow tract obstruction relief or aortic valve replacement in 4 and tricuspid valve repair in 2. The new mitral valve was mechanical in 20 and xenograft in 2. Median valve size increased from 21 mm to 25 mm although 7 valves were not upsized on rereplacement (average valve size increase was 3.3 +/- 1 mm). Only 2 patients (9%) needed a new pacemaker. There were no hospital deaths. Six children developed end-stage heart failure and underwent successful cardiac transplantation 3 to 32 (mean 12.1 +/- 10.0) months, postoperatively. On follow-up of 1 month to 7.7 years (mean 2.5 +/- 2.3 years) there has been only one late death of an unrecognized coronary artery anomaly. CONCLUSIONS: Redo MVR in children can be performed safely with low morbidity and mortality. A larger prosthesis can often be placed in these children. A surprisingly high percentage of patients eventually require transplantation, perhaps reflecting unnecessary delay in referral for redo MVR.

Adolescent↗
PubMed1986

[Syndrome of mitral valve prolapse: past, present and prospects].

A short history of mitral valve prolapse was reviewed to learn what was the knowledge we have and to recognize what should be resolved at the present time and in the near future. Particular emphasis was placed on the detailed studies performed in Japan as compared to those of occidental countries. Prevalence of mitral valve prolapse largely depends on the methods of investigation and is definitely related to the diagnostic criteria. Among those, the echocardiographic criteria are particularly important, but there are pitfalls which cause over- or underdiagnosis. Auscultatory criteria, which should be confirmed by phonocardiography, are not sensitive enough because of the presence of "silent" prolapse, though the auscultatory acumen of the averaged doctors is quite often unexpected. DaCosta syndrome and the related conditions have some connections with mitral valve prolapse syndrome. The relation should extensively be studied, because somatic and mental signs are not conclusively related to the anatomical abnormalities and the cases with borderline prolapse tend to have definite signs and symptoms. Natural course of mitral valve prolapse based on the long follow-up study is far from the conclusion. So far, no comprehensive cases with well-known natural history of this entity. Prognosis should be carefully evaluated, because most of the patients are doing well and several ominous prognostic signs, such as sudden deaths, are thought to be overemphasized.

Echocardiography↗
PubMed2003

Prevalence of mitral valve prolapse in Stickler syndrome.

The prevalence of mitral valve prolapse in Stickler syndrome has been reported to be much higher than in the general population. As a result, it has been recommended that all patients with Stickler syndrome undergo routine echocardiography and have antibiotic prophylaxis prior to surgery. The purpose of this study was to evaluate the prevalence of mitral valve prolapse in a large cohort of UK patients with Stickler syndrome in whom the clinical diagnosis has been confirmed by molecular genetic analysis. Probands and pedigrees were identified from the Vitreoretinal Service database according to previously published criteria. Ophthalmic, skeletal, audiometric, and orofacial features were assessed. Affected individuals underwent a full cardiological examination including auscultation and two-dimensional echocardiography. Mutation analysis of the COL2A1 and COL11A1 genes was carried out. Seventy-eight patients from 25 pedigrees were studied. Mutation analysis confirmed the clinical diagnosis in every pedigree. No patient was found to have clinical evidence of cardiovascular disease and no patient had significant mitral or other valvular prolapse on echocardiography. These data from a large cohort of UK patients with proven Stickler syndrome do not suggest an increased incidence of mitral valve prolapse over and above that found in the general population. Routine echocardiography screening and use of preoperative antibiotics are unnecessary and should be reserved for those individual cases where there is clear clinical indication.

Cohort Studies↗
PubMed1991

Optimal exposure of the mitral valve through an extended vertical transeptal approach.

The mitral valve was approached through a vertical transeptal incision extended into the roof of the left atrium in 111 patients. Good exposure was invariably provided even in unfavorable situations such as a small left atrium combined with right ventricular hypertrophy or a previously implanted aortic prosthesis. The only hospital death in the entire series was not related to this approach to the mitral valve. Due to breakage of the suture in the roof of the left atrium and to incomplete reconstruction of the atrial septum resulting in a large left-to-right shunt, 2 patients required reinstitution of cardiopulmonary bypass. Both had a smooth postoperative course. Other intra- or postoperative complications related to the incision did not occur. Duration of cardiopulmonary bypass and aortic occlusion was not significantly different from that of patients operated upon through the conventional left atrial approach in the year preceding the experience embraced by this study. Only 3 of 52 patients who were preoperatively in sinus rhythm were discharged in atrial fibrillation. Enhanced atrial vulnerability was demonstrated preoperatively in all 3. These data support a wide application of the extended vertical transeptal approach in mitral valve surgery.

Adult↗
PubMed1992

Long-term follow-up results after reconstruction of the mitral valve by leaflet advancement.

In this study, we discuss the clinical results of mitral leaflet advancement performed on 29 patients over the past 10 years and attempt to determine the indication. Preoperative diagnosis of mitral valve lesion consisted of mitral regurgitation in 21 patients and mitral stenosis in 8 patients. Mitral valve repair was applied to the anterior mitral leaflet in 2, the posterior mitral leaflet in 25, and bilateral leaflets in 2 patients. Reoperation was performed on 13 patients, and 1 patient died of renal failure immediately after reoperation. No reoperation was needed for 96.6% of the patients at 1 year, 89.5% at 5 years, 75.0% at 8 years, 63.8% at 10 years, and 52.6% at 15 years postoperatively. At reoperation, the repaired mitral leaflet was found to be calcified in 3 patients more than 9 years after the initial operation. Of the 12 survivors without reoperation, mitral stenosis associated with regurgitation was obvious in 6 patients. Of the 21 patients with preoperative mitral regurgitation, 90.0% showed no deterioration at 5 years, 79.7% at 8 years, and 69.1% at 10 years. On the other hand, for the 8 patients with mitral stenosis, the rates were 87.5% at 1 year, 62.5% at 5 years, 50.0% at 8 years, and 25% at 10 years. Our results suggest that mitral leaflet advancement shows satisfactory results in patients with mitral regurgitation but is not successful for patients with mitral stenosis in the long term because the repaired valve tends to be stenotic in the late postoperative period.

Adolescent↗
PubMed1999

Mitral valve replacement with preservation of the subvalvular apparatus.

The introduction of the Starr-Edwards valve allowed complete replacement of diseased left-sided heart valves. With improved cardiopulmonary bypass, myocardial protection, and surgical techniques the mortality rate from aortic valve replacement decreased substantially, whereas the mortality rate from mitral valve replacement remained high, largely because of low cardiac output syndrome. Increasing use of mitral valve repair techniques resulted in a marked decrease in short-term and long-term morbidity and mortality when treating patients with mitral regurgitation. Some believed that this resulted from maintenance of the mitral annular papillary muscle continuity during mitral valve repair. Subsequent experimental and clinical studies have validated the positive short-term and long-term effects of maintaining the integrity of the mitral valve subvalvular apparatus. This article considers the history of the clinical use of preservation of the subvalvular apparatus, the physiologic studies examining this concept, and the clinical data available on its use. It also examines the following: 1) mitral stenosis versus mitral regurgitation and the preservation of the subvalvular apparatus; 2) whether the anterior, posterior, or both areas of the subvalvular apparatus should be preserved; and 3) the surgical techniques for the preservation of the subvalvular apparatus and valve implantation.

Animals↗
PubMed1981

Mitral-valve prolapse: prevalence in an Australian population.

The prevalence of mitral-valve prolapse in 200 volunteers (100 men and 100 women) was investigated by means of a combination of clinical, phonocardiographic, and echocardiographic findings. Mitral valve prolapse was documented on M-mode echocardiography in four men and four women, giving an over-all prevalence of 4%. In addition, symptoms and electrocardiographic abnormalities, which are reported to occur more commonly in patients with mitral valve prolapse, occurred with equal frequency in the subjects with mitral valve prolapse and in those without prolapse.

Adolescent↗
PubMed2005

Non-linear fluid-coupled computational model of the mitral valve.

BACKGROUND AND AIM OF THE STUDY: The dynamics of the mitral valve result from the synergy of left heart geometry, local blood flow and tissue integrity. Herein is presented the first coupled fluid-structure computational model of the mitral valve in which valvular kinematics result from the interaction of local blood flow and a continuum representation of valvular microstructure. METHODS: The diastolic geometry of the mitral valve was assembled from previously published experimental data. Anterior and posterior leaflets were modeled as networks of entangled collagen fibers, embedded in an isotropic matrix. The resulting non-linear continuum description of mitral tissue was implemented in a three-dimensional membrane formulation. Chordal tension-only behavior was defined from experimental tensile tests. The computational model considered the valve immersed in a domain of Newtonian blood, with an experimentally determined viscosity corresponding to a shear rate of 180 s(-1) at 37 degrees C. Ventricular and atrial pressure curves were applied to ventricular and atrial surfaces of the blood domain. RESULTS: Peak closing flow and volume were 51 ml/s and 1.17 ml, respectively. Papillary muscle force ranged dynamically between 0.0 and 2.6 N. Acoustic pressure (RMS) was found to be 3.3 Pa, with a peak frequency of 72 Hz at 0.064 s from the onset of systole. Model predictions showed excellent agreement with available transmitral flow, papillary force and first heart sound (S1) acoustic data. CONCLUSION: The addition of blood flow and an experimentally driven microstructural description of mitral tissue represent a significant advance in computational studies of the mitral valve. This model will be the foundation for future computational studies on the effect of pathophysiological tissue alterations on mitral valve competence.

Algorithms↗
PubMed1992

Use of transoesophageal echocardiography to detect left atrial thrombi before percutaneous balloon dilatation of the mitral valve: a prospective study.

OBJECTIVE: Systemic emboli related to atrial thrombi are a well known complication of percutaneous balloon dilatation of the mitral valve. The presence of left atrial thrombi therefore, is believed to be a contraindication to balloon dilatation. The purpose of this study was to determine the frequency of left atrial thrombi in patients referred for balloon dilatation of the mitral valve, the added benefit of pre-procedural transoesophageal echocardiography, and to identify factors that predicted left atrial thrombi. DESIGN: Prospective study over a 14 month period of 20 consecutive patients by cross sectional transthoracic echocardiography 24-48 hours before balloon dilatation of the mitral valve and by transoesophageal echocardiography immediately before the procedure. RESULTS: One patient had a left atrial thrombus detected by transthoracic study. Two patients (10%) had left atrial thrombi identified by transoesophageal echocardiography. In both valve dilatation was not attempted and the thrombi were confirmed at surgery. The remaining 18 patients all underwent successful balloon dilatation of the mitral valve without clinical evidence of an embolic event. No association was found between patient age, mitral valve area, transmitral gradient, left atrial size, presence of atrial fibrillation, severity of mitral regurgitation, cardiac output, or the presence of left atrial swirling and an increased prevalence of atrial thrombi. CONCLUSION: Left atrial thrombi are often seen despite long term systemic anticoagulation in patients referred for balloon dilatation of the mitral valve. The frequency of unsuspected left atrial thrombi detected by transoesophageal echocardiography was similar to the reported frequency of embolic events after balloon dilatation of the mitral valve. Transoesophageal echocardiography for the identification of left atrial thrombi is strongly recommended in all patients before balloon dilatation of the mitral valve including those treated with systemic anticoagulation and those who have had a normal transthoracic echocardiographic study.

Adult↗
PubMed1984

[Diagnostic value of echocardiographic examinations in the evaluation of patients with infectious endocarditis of aortic and/or mitral valve localization].

We estimated sensitivity, specificity, predictive value and efficiency of echocardiography in detecting vegetations and ruptured valves in patients with aortic and/or mitral valves infective endocarditis. We studied two groups of patients, in whom both high quality echocardiography examination and surgical inspection of heart valves were available. Group I: 16 patients (32 valves) with aortic and/or mitral valves endocarditis and surgical demonstration of vegetations and/or ruptured valves. In this group the prevalence of vegetations was 65.6%, the prevalence of ruptured valves was 43.7%. Group II was composed of the 16 patients of group I with endocarditis and of 93 other patients without endocarditis. In this group (139 valves) the prevalence of vegetations was 15%, the prevalence of ruptured valves was 13.6%. Echocardiographic detection of valve vegetations. Sensitivity (71.4%) was the same in group I and II. Specificity was 91% in group I and 91.5% in group II. The positive predictive value was 93.7% in group I and 60% in group II. The negative predictive value was 62.5% and 94.7% respectively. Echocardiographic detection of ruptured valves: sensitivity was 50% in I and 42% in group II. Specificity was 94.4% in group I and 99% in group II. The positive predictive value was 87.5% in group I and 89% in group II. The negative predictive value was 70.8% in group I and 91.5% in group II. The echocardiographic efficiency was higher in group II: 88.4% for vegetations and 91.3% for ruptured valves. This reflects the high specificity and the high definition of normal valves in this unselected low-risk group. The efficiency was lower in group I: 78% for vegetations and 75% for ruptured valves. This reflects the poor sensitivity and the failure of the test to identify all the vegetations or the ruptured valves in this selected high-risk group.

Adolescent↗
PubMed2002

Cleft of the mitral valve in patients with Down's syndrome.

Differentiation between a cleft of the mitral valve and the cleft of the left side of an atrioventricular septal defect--a lesion commonly found in patients with Down's syndrome--is surgically important since the distribution of the conduction tissue varies between the 2 lesions. We sought to determine if cleft of the mitral valve occurs also in patients with Down's syndrome. We studied 5 patients with Down's syndrome and cleft of the mitral valve followed in our institution. Echocardiography showed in all 5 patients a cleft dividing the anterior (aortic) leaflet of mitral valve with normal papillary muscle position, mural leaflet size, and ratio of the inlet/outlet dimension of the left ventricle. Associated cardiac lesions were present in all 5 patients: perimembranous ventricular septal defect in 3, ostium secundum atrial septal defect in 2 and patent ductus arteriosus in 2 patients. During the 5.6 years (0.2-11) of the follow-up period, surgical repair of the cleft was never indicated since the mitral regurgitation through the cleft remained mild or absent in all the patients. Two patients underwent closure of a ventricular septal defect, with atrial septal defect closure in one and ductal ligation in 2. One patient died suddenly at home, without evidence of a cardiac cause. In conclusion, a cleft of the mitral valve has important developmental and morphologic differences with atrioventricular septal defect and may occur in patients with Down's syndrome. If surgical repair of the cleft or of associated cardiac lesion is indicated, it is necessary to distinguish it from atrioventricular septal defect where the conduction axis is displaced posteriorly and may be exposed during surgery.

Diagnosis, Differential↗
PubMed1982

Mitral valve prolapse in a runner.

In the past decade mitral valve prolapse has become a popular diagnosis. This may be related to the increased utilisation of cardiac ultrasound diagnostic techniques. Although many initial medical articles highlighted patients with complications of mitral valve prolapse, the natural history of isolated mitral systolic click is benign. Complications are sudden cardiac death, symptomatic cardiac arrhythmias, endocarditis, ruptured chordea tendinae, progressive mitral regurgitation, and cerebral ischemic events. However, these occur more likely in patients with MVP and associated mitral regurgitation and/or ECG repolarization abnormalities. The subject in this case example had nonanginal chest pain possibly related to silent mitral valve prolapse, documented on echocardiography. There is a coincidental finding of "athletic heart" on electrocardiogram. Stress ECG and thallium scintography showed excellent cardiorespiratory fitness and normal myocardial perfusion. He was given reassurance that there was no significant cardiac problem, and subsequently completed a marathon run without consequence.

Adult↗
PubMed1989

Colour Doppler echocardiographic assessment of regurgitant flow in mitral valve prolapse.

Colour flow mapping was used to examine the pattern of regurgitant flow in 46 patients with mitral regurgitation due to mitral valve prolapse. Valve morphology was assessed from the real-time two-dimensional image and the presence of mitral regurgitation was determined from real time Doppler. On morphological criteria 11 (24%) patients had isolated or predominant anterior leaflet prolapse, 22 (48%) patients posterior and 13 (28%) patients bi-leaflet prolapse. A single regurgitant jet was detected in 43 patients (93%) and multiple jets in three (7%). The direction of the regurgitant jet was assessed in multiple views in two orthogonal planes (antero-posterior and medial-lateral) defined in relation to the mitral valve leaflets. The regurgitant jet was eccentric in the antero-posterior plane of the mitral leaflets in 40 of 45 (89%) cases and in the medial-lateral plane in 36 of 40 (90%) cases. Posterior leaflet prolapse was usually associated with antero-medially directed jets, anterior leaflet prolapse with postero-central or postero-lateral jets and bi-leaflet prolapse with predominantly postero-medial jets. In a subgroup of patients with significant mitral regurgitation and an eccentric regurgitant jet, a 'swirling' effect was produced with late systolic flow in the body of the left atrium toward the mitral valve. Colour flow mapping in patients with mitral regurgitation due to mitral valve prolapse demonstrated eccentric jets in most patients. The direction of regurgitant flow appeared to depend greatly on the dynamic anatomy of the mitral valve leaflets during systole. Although a single jet was detected in most patients, multiple jets did occur in a minority.

Echocardiography, Doppler↗
PubMed2003

[Possibilities of stress-echocardiography in diagnostics of pathology of mitral valve. Part II].

The paper deals with different aspects of application of stress-echocardiography for assessment of mitral valve disease (acquired stenosis or insufficiency, mitral regurgitation due to ischemic heart disease and mitral valve prolapse). Continuity equation is preferable to pressure half-time and resistance for estimation of hemodynamic significance of mitral stenosis. In some patients studies at rest reveal only slight mitral regurgitation while during stress it becomes hemodynamically significant and associated with pronounced elevation of pulmonary artery pressure. Deterioration of left ventricular function in this pathology often occurs before appearance of symptoms and even before increase of left ventricular dimensions and lowering of ejection fraction can be registered by echocardiography at rest. In patients with mitral valve prolapse stress induced mitral regurgitation has high predictive power for unfavorable clinical course. It is necessary to remember that in this group of patients abnormalities of left ventricular function during stress can be found in the absence of ischemic heart disease or pronounced regurgitation.

Echocardiography, Stress↗
PubMedDate not supplied

[Hemolysis after bioprosthesis implantation in the mitral valve].

Rare case of hemolysis following an implantation of the biological mitral valve is presented. In 1985, biological mitral valve of Ionescu-Shiley type was implanted to a 45-year female patient for post-rheumatic mitral defect. Patient was in the III NYHA class before surgery. Her health status improved after operation. Several echocardiographic examinations have shown normal functioning of the implanted valve (normal gradient across the valve, no retrograde wave). Upper respiratory infection with subsequent progressive weakness, anemia, yellow skin, and heart failure occurred in 1991. Echocardiography has shown significant increase (twice) in the gradient across the valve (max 26, mean--14 mm Hg) and retrograde wave of the II degree as well as mitral insufficiency of the II degree. Laboratory tests have shown marked anemia with reticulosis, increase in blood bilirubin, increase in LDH activity (by about ten times), and a decrease in haptoglobins. Mitral valve dysfunction with hemolysis has been diagnosed. Patient was reoperated. Intraoperatively, incompletely healed valvular ring, and lesions to the leaves such as: fibrosis, thickening and partial deficits. Biological mitral valve was replaced with Corin-Carbotest artificial valve. Postoperative course was uncomplicated.

Anemia, Hemolytic↗
PubMed1996

[Contribution of multiplane transesophageal echocardiography in the study of mitral valve prostheses].

Many reports have confirmed the value of transoesophageal echocardiography in the diagnosis of mechanical mitral valve prosthesis dysfunction: new biplane and multiplane probes seem to provide additional information in the assessment of cardiac disease. The aim of this study was to quantify the additional value of these new probes in the assessment of mitral valve prostheses. Seventy-five mitral valve prostheses were assessed with the multiplane probe, 45 normal bileaflet prostheses, 17 with regurgitant dysfunction and 12 with non obstructive thrombi and/or strands, and one with a blocked leaflet. In order to compare the respective values of monoplane, biplane and multiplane probes, the recordings were performed at 0 degrees, 90 degrees and from 0 degrees to 180 degrees in continuous sweep mode through the scanning plane. Globally, with the monoplane assessment, it was only possible to visualise both leaflets simultaneously in 13% of cases. The majority of prostheses was correctly analysed between 60 and 100 degrees. This was of paramount importance for the diagnosis of blockage of one leaflet. With respect to para-prosthetic valve regurgitation, the transverse view allowed visualisation of the lateral and paraseptal annular regions. The addition of a longitudinal view allowed visualisation of anterior and posterior regurgitant jets: the supplementary views provided by the multiplane probe allowed detection of small regurgitant jets in the diagonal planes between the longitudinal and transverse views. The multiplane probe offers the possibility of identifying the precise origin of the jet and helps quantification and peroperative localisation of its position. Small, non-obstructive thrombi and strands are better seen using a multiplane probe, especially when of small size. Therefore, multiplane transoesophageal echocardiography improves the assessment of mitral valve prostheses, the majority of diagnoses being, however, accessible with biplane probes.

Echocardiography, Transesophageal↗
PubMed1980

Echocardiographic source of early anterior systolic motion in late systolic mitral valve prolapse.

The echocardiographic features of patients with parachute mitral valve have revealed the combination of an early systolic movement of the mitral valve and late systolic prolapse. Cross-sectional echocardiographic and angiographic studies showed that the early systolic anterior motion was produced by the presence of a flail scallop of the anterior mitral leaflet in the left ventricular outflow tract.

Echocardiography↗