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At least 721 records · Page 40Linked to original sources
PubMed1982

Mid-diastolic aortic valve opening in bacterial endocarditis of aortic valve.

Echocardiographic features of acute aortic regurgitation resulting from bacterial endocarditis have been well documented (Nathan et al., 1980; Weaver et al., 1977; Wray, 1975a), and include thick shaggy echoes from aortic valve in diastole, fine diastolic flutter of aortic valves suggestive of rupture of cusps, and premature closure of mitral valves. Echocardiography being a sensitive noninvasive technique for detecting aortic valve vegetations is heavily relied on for earlier diagnosis and prompt therapy of these patients. Prognosis of echocardiographically positive endocarditis is known to be worse than for echo-negative patients. The following case is being presented because of an unusual echocardiographic manifestation with mid-diastolic aortic valve opening secondary to flail aortic valve from staphylococcal endocarditis of the aortic valve.

Adult↗
PubMed1989

Doppler echocardiographic assessment of transmitral gradients and mitral valve area before and after mitral valve balloon dilatation.

This is a comparative study of 60 sets of observations of mitral valve end-diastolic gradient, mean diastolic gradient, and mitral valve area obtained by Doppler echocardiography and cardiac catheterization. The studies were performed in 28 patients, 16 of whom underwent mitral valve balloon valvuloplasty. These 16 patients had studies performed before, immediately after valvuloplasty, and one week later. Thus 28 studies were performed before or without valvuloplasty (Group I) and 32 after valvuloplasty (Group II). The time interval between Doppler echocardiography and cardiac catheterization was less than 24 hours in 44 studies and 24 to 72 hours in 16 studies. In Doppler echocardiography the gradients were obtained by simplified Bernoulli's equation and the mitral valve area by pressure half-time method. There was excellent correlation between end-diastolic gradients (r = 0.96, p less than 0.001) and mean diastolic gradients (r = 0.92, p less than 0.001) measured by the two techniques. A statistically significant correlation also existed in the mitral valve area values (r = 0.53, p less than 0.005). On separate analysis Group I showed excellent correlation for all three variables (r values of 0.90, 0.87, and 0.82 for end-diastolic gradients, mean-diastolic gradients, and mitral valve area, respectively). Group II also showed excellent correlation of end-diastolic gradients (r = 0.80) and mean diastolic gradients (r = 0.87), but poor correlation of the mitral valve areas (r = 0.17; p = NS) by the two techniques. Doppler echocardiography can accurately measure transmitral gradients both before and after valvuloplasty.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

The relationship between new cardiac conduction defects and extension of valve infection in native valve endocarditis.

New conduction defects in the setting of native valve infective endocarditis (IE) are commonly believed to be associated with direct extension beyond the free valve area. At University Hospital in Newark, among 100 cases of IE, in none of five instances of associated conduction defects (excluding first-degree heart block) was this the case. In neither of two instances of direct extension of valve infection was this accompanied by a new conduction defect. To explore this relationship, autopsy, surgical, and echocardiographic findings from other institutions were combined with these data. Among 47 instances of new conduction defects in IE, only 60% could be related to direct extension of valve infection. The cause was coronary embolization in 4% and unknown in 36%. Among 119 cases of complicated valve lesions, significant conduction defects were documented by ECG in only 15%. In IE the appearance of new conduction abnormalities may often result from causes other than extension of valve infection. Furthermore, complicated valve lesions may often be present without electrocardiographic evidence, indicating interruption of normal conduction pathways.

Abscess↗
PubMed2005

Papillary fibroelastoma of the mitral valve associated with rheumatic mitral valve stenosis.

With the advent of echocardiography, diagnosis of papillary fibroelastoma in living patients has been made possible, yet papillary fibroelastoma found in the living remains a very rare cardiac tumor. We report a case of papillary fibroelastoma of the mitral valve with rheumatic mitral valve stenosis. A 68-year-old woman was referred to our hospital with a mitral valve tumor and rheumatic mitral valve stenosis. She underwent anticoagulation therapy with Warfarin for 8 years since having a cerebral embolization. Echocardiography revealed a mass attached to the mitral valve, with severe mitral valve stenosis. Electrocardiography demonstrated a chronic atrial fibrillation. Tumor excision with mitral valve replacement and maze procedure were performed. Both the surgical and histological findings depicted papillary fibroelastoma. The postoperative course was uneventful and the patient has remained symptom-free one year after surgery.

Aged↗
PubMed2005

Staged initial percutaneous coronary intervention followed by valve surgery ("hybrid approach") for patients with complex coronary and valve disease.

OBJECTIVES: The goal of this study was to determine if a "hybrid" approach to the treatment of complex combined coronary and valve disease is superior to the results predicted by a Society of Thoracic Surgeons' (STS) algorithm with conventional coronary artery bypass graft (CABG)/valve surgery in high-risk patients. BACKGROUND: With advancements in percutaneous coronary interventions (PCIs), some patients requiring coronary revascularization and valve surgery may benefit from a hybrid approach involving initial planned PCI followed by valve surgery, rather than conventional CABG/valve surgery. METHODS: We retrospectively analyzed 26 consecutive patients with coronary artery and valve disease who underwent planned initial PCI followed by valve surgery during the same hospital stay between September 1997 and August 2003. We calculated the predicted mortality at the time of PCI and compared it with the observed mortality. RESULTS: There were 12 male and 14 female patients with a median age of 72 years (range 53 to 91 years). Balloon angioplasty was performed in all patients, followed by stenting in 22 (85%) patients. Within a median of 5 days (range 0 to 14 days), 15 patients (58%) underwent primary and 11 patients (42%) underwent re-operative valve surgery. Operative mortality was 1 of 26 patients (3.8%), dramatically lower than the STS-predicted mortality of 22%. Median blood loss was 900 ml, and 22 patients (85%) required blood transfusions. Survival at 1, 3, and 5 years was 78%, 56%, and 44%, respectively. CONCLUSIONS: Hybrid initial PCI followed by staged valve surgery represents an excellent alternative to conventional CABG/valve surgery in some high-risk patients, particularly those who present in shock after myocardial infarction. Lower mortality rates come at the cost of more bleeding and transfusion requirements.

Aged↗
PubMed1976

A comparative study of 48 host valve and 24 prosthetic valve endocarditis cases.

Forty-eight cases of host valve endocarditis and 24 cases of prosthetic valve endocarditis occurring during a concurrent period of time were analyzed to assess differences between the two groups. The over-all incidence of prosthetic valve endocarditis during this 40 month period was 4.4%. The symptoms and signs in both groups were similar, except that PVE patients had more frequent occurrences of changing heart murmurs and splenic and cerebral emboli. Spleen scans may be helpful in the diagnosis of selected cases of culture-negative prosthetic valve endocarditis. There was no significant difference between the two groups for the various infecting microorganisms. However, the culture-negative prosthetic valve group had a mortality rate of 77.7% compared to 46.2% for the host valve group. In the HVE patients the oral cavity or urinary tract was the probable source of infection in 50.0% of the patients. In about one third of HVE cases, there was strong evidence that the infection was related to a therapeutic procedure, whereas nearly half of the PVE patients had clinical evidence of an extracardiac infection at the time of open-heart surgery. We emphasize the need for good pre- and postoperative surveillance to eliminate possible predisposing infections and appropriate antibiotic prophylaxis in all patients with valvular disease at times of risk. The survival rate in patients with prosthetic valve endocarditis was highest in those patients who received "appropriate" antibiotics and, if significant congestive heart failure was present, surgical intervention was necessary.

Adolescent↗
PubMed1985

Valve replacement in patients with native valve endocarditis: what really determines operative outcome?

The influence of 27 variables on operative mortality and late complications (defined as residual or recurrent endocarditis or late bland periprosthetic leak) was determined using discriminant analysis for 108 patients undergoing valve replacement for native valve endocarditis at Stanford University Medical Center from March, 1964, to January, 1983. Congestive heart failure was the indication for valve replacement in 86% of patients. Aortic valve replacement was required in 68% and mitral valve replacement, in 26%. Patients were arbitrarily defined as having active (58%) or healed (42%) endocarditis. Follow-up included 515 patient-years and extended to a maximum of 19 years. Operative mortality was 15 +/- 4%, and 17 patients had late complications (linearized rate, 3.3% per patient-year). Seven variables were significantly related to operative mortality in the univariate analysis, but only organism (Staphylococcus aureus versus all others, p = 0.0302) was a significant independent predictor of operative mortality. For late complications, only 2 of 7 significant univariate covariates proved to be significant independent determinants: organisms on valve culture or gram stain and the presence of annular abscess. Patients with S. aureus endocarditis not showing prompt response to antibiotic treatment must be considered for early operation. Similarly, timely operative intervention for patients with annular abscess will be essential in decreasing late valve infections and perivalvular leaks.

Actuarial Analysis↗
PubMed1989

Heart valve replacement with the Björk-Shiley monostrut valve in patients over 60 years of age.

Over a period of five years (1983-88) 210 Björk-Shiley monostrut mechanical tilting disc prostheses were implanted in 176 patients over the age of 60. There were 61 aortic valve replacements, 86 mitral valve replacements and 29 multiple replacements. Patients were aged between 61 and 78 years (mean 65.5 years), 89% were in NYHA grades III and IV preoperatively and 34.6% had had previous cardiac surgery. Concomitant coronary surgery was performed in 15.9%. Early mortality was 9.1%. Follow-up is 100% complete. There were eight late deaths (3.1 per 100 patient years) of which three were valve-related (prosthetic endocarditis 2, periprosthetic leak 1). Actuarial survival at five years is 98% for aortic valve replacement and 93% for mitral valve replacement. There were no major embolic events and four possible minor embolic events. Overall freedom from anticoagulant complications was 88.9% at five years. No deaths occurred because of anticoagulant-related haemorrhage. There were no episodes of valve failure (thrombotic obstruction or mechanical disruption). Six patients were reoperated for complications: two for periprosthetic leak and three for prosthetic endocarditis. These results compare favourably with those of other valve substitutes and justify the continuing use of the Björk-Shiley monostrut tilting disc prosthesis in the elderly.

Anticoagulants↗
PubMedDate not supplied

Novel cardiac assist valve with a purge flow in the valve sinus.

Clinical applications of cardiac assist systems continue to have a severe problem, that of thromboembolic complications. The problem originates mainly at the valves, which are usually made of a antithrombogenic material, such as bovine pericardium. However, the valve housing is made of a less suitable material, and wherever the blood flow is stagnant, a thrombus is likely to form. Such stagnant blood flow is found in the space between the housing of the valve and the leaflets, in the sinuses. Consequently, thrombi often are generated in the sinuses. The novel valve design presented in this article avoids the formation of the stagnation zone in the sinuses by a purge flow. This flow is taken from the main flow through the valve and is directed into each sinus of the res purges the sinuses. The purge flow effect is investigated with an experimental method in which the sinus is filled with dye, and washout during the valve action is observed and recorded on videotape, which is compared with washout in a valve without a purge flow. In addition, the purge flow effect is investigated by computational fluid dynamics. Both methods show that the purge flow effectively increases fluid exchange in the sinuses.

Computer Simulation↗
PubMed1982

Two dimensional echocardiographic assessment of aortic valve morphology: feasibility of bicuspid valve detection. Prospective study of 100 adult patients.

Two dimensional echocardiographic criteria for bicuspid aortic valve recognition have greater specificity than previously proposed M-mode echocardiographic criteria. The potential clinical use of the two dimensional technique is, however, limited by the technical inability to image adequately the aortic valve leaflets in many patients. One hundred consecutive adult patients undergoing two dimensional echocardiography were prospectively studied. Valve cusp number could not be determined because of dense calcification in eight patients. A bicuspid aortic valve was diagnosed in a single subject. A parasternal short axis view disclosed three commissures (diastolic "Y" configuration) in only 26 patients. Technically adequate parasternal short axis imaging was more likely in younger patients and in non-smokers. In patients not successfully imaged from the parasternal approach, an anteriorly tilted apical four chamber view showed a diastolic "Y" configuration in an additional eight cases. Considering the high prevalence in our population of incomplete two dimensional echocardiographic aortic valve leaflet imaging, angiographic and/or pathological studies must be performed to establish the correlation between these incomplete echocardiographic patterns and aortic valve anatomy if two dimensional echocardiography is to have widespread application in the diagnosis of the congenital bicuspid aortic valve.

Adolescent↗
PubMed1988

Hour-glass deformity of the pulmonary valve: a third type of pulmonary valve stenosis.

In the 12 years from 1975 to 1987, 55 patients had open pulmonary valve surgery for isolated congenital stenosis of the pulmonary valve. Three types of pulmonary stenosis were seen: (a) dome-shaped pulmonary stenosis (34 patients); (b) dysplastic pulmonary valves with thick cauliflower-like cusps (12 patients), and (c) hour-glass deformity of the pulmonary valve, with "bottle-shaped" sinuses (nine patients). This third type has not been described before. Preoperative identification of the valve structure is important because the choice of treatment (balloon dilatation for some dome-shaped valves and excision for dysplastic and hour-glass valves) depends on the type of stenosis.

Adolescent↗
PubMed1997

A study of 47 bacteremic Staphylococcus aureus endocarditis cases: 23 with native valves treated surgically and 24 with prosthetic valves.

A retrospective review of medical records from the Staphylococcus Laboratory, Copenhagen, 1982-1991, was carried out at the Department of Clinical Microbiology, Statens Serum Institut, 1994-1995, to investigate the clinical features and outcome of two subgroups of bacteremic Staphylococcus aureus endocarditis cases in non-drug addicts: patients with prosthetic valve endocarditis (PVE) and patients with native valve endocarditis treated surgically. Twenty-four cases of PVE were included. Six cases were early (within 60 days of valve implantation) and 18 were late. The overall in-hospital mortality was 42%. Surgical treatment resulted in a non-significantly lower mortality as compared with medical treatment alone (0% vs 50%, p = 0.19). Medical treatment of aortic and mitral valve endocarditis resulted in similar mortality rates (44% and 50%, respectively). Twenty-three cases of native valve infective endocarditis had the valve replaced surgically. The in-hospital mortality was 22%, which was significantly lower as compared with medical therapy (69%, p < 0.0001). The treatment changed significantly during the study period: 6 of 112 patients (5%) were treated surgically in the first half of the period (1982-1986) compared to 17 of 124 patients (14%) in the second half (1987-1991, p = 0.049). Severe congestive heart failure was the main indication for cardiac surgery in 21 patients. In conclusion, a shift towards a more aggressive surgical approach has taken place in the 10-year period. This development should be strengthened in the future as surgical intervention may improve survival in patients with infective endocarditis caused by S. aureus whether the infected valve is prosthetic or native.

Aged↗
PubMed2005

Systolic anterior motion of the mitral valve after mitral valve repair: a method of prevention.

Factors predisposing patients to systolic anterior motion of the mitral valve (SAM) with left ventricular outflow tract (LVOT) obstruction after mitral valve repair are the presence of a myxomatous mitral valve with redundant leaflets, a nondilated hyperdynamic left ventricle, and a short distance between the mitral valve coaptation point and the ventricular septum after repair. From December 1999 through March 2000, we used our surgical method in 6 patients with severely myxomatous regurgitant mitral valves who were at risk of developing SAM. Leaflets were markedly redundant in all 6. Left ventricular function was hyperdynamic in 4 patients and normal in 2. Triangular or quadrangular resection of the midportion of the posterior leaflet and posterior band annuloplasty were performed. To prevent SAM and LVOT obstruction, extra, posteriorly directed, mid-posterior-leaflet secondary chordae tendineae, which would otherwise have been resected, were transferred to the underside of the middle of the mid-anterior leaflet with a small piece of associated valve as an anchoring pledget. This kept the redundant anterior leaflet edge, which extended below the coaptation point, away from the LVOT No post-repair SAM or LVOT obstruction was observed on intraoperative or discharge echocardiography. All patients had no or trivial residual mitral regurgitation. We conclude that extra chordae tendineae, when available, can be used in mitral valve repair to tether the redundant anterior leaflet and thus prevent it from flipping into the LVOT. This will theoretically prevent SAM and LVOT obstruction in patients with risk factors for SAM.

Cardiac Surgical Procedures↗
PubMed1984

The nipple valve as a sphincter substitute for the ileocecal valve: prevention of bacterial overgrowth in the small bowel.

We evaluated the bacteriologic effect of a nipple valve substitute for the ileocecal valve in a canine model. Resection of the ileocecal valve and the distal 40% of the jejunoileum with end-to-end anastomosis was carried out in 10 dogs. In five of the dogs chosen randomly, a nipple valve was constructed at the anastomosis; in the remainder , a two-layer jejunocolostomy was formed. Microbiologic samples were taken at operation in the ascending colon and at three sites in the small intestine before resection and at reoperation 4 weeks later. These revealed a dramatic increase in anaerobic bacteria in the distal jejunum following jejunocolostomy without valve insertion but no increase following jejunocolostomy with nipple valve. There was a seven-log difference between the two groups in the mean anaerobic bacterial counts (P less than 0.05) measured 60 cm proximal to the anastomosis at the second operation. Results of aerobic cultures were similar but less dramatic. We conclude that construction of a nipple valve jejunocolostomy prevents anaerobic bacterial colonization of the proximal small bowel and may therefore be useful in the treatment or prevention of short bowel syndrome.

Animals↗
PubMed1996

Tissue-engineered heart valves. Autologous valve leaflet replacement study in a lamb model.

BACKGROUND: We have previously reported the successful creation of tissue-engineered valve leaflets and the implantation of these autologous tissue leaflets in the pulmonary valve position. This study was designed to trace cultured cells that were seeded onto a biodegradable polymer with the use of a 1,1'-dioctadecyl-3,3,3' 3'-tetramethylindo-carbocyanine perchlorate (Di-1) cell-labeling method. We also examined the time-related biochemical, biomechanical, and histological characteristics and evolution of these tissue constructs. METHODS AND RESULTS: Mixed cell populations of endothelial cells and fibroblasts were isolated from explanted ovine arteries. Endothelial cells were selectively labeled with an acetylated low density lipoprotein marker and separated from fibroblasts with the use of a fluorescence-activated cell sorter. A synthetic biodegradable scaffold consisting of polyglycolic acid fibers was seeded first with fibroblasts, then coated with endothelial cells. Using these methods, we implanted autologous cell/polymer constructs in six animals. In two additional control animals, a leaflet of polymer was implanted without prior cell seeding. In each animal, cardiopulmonary bypass was used to completely resect the right posterior leaflet of the pulmonary valve and replace it with an engineered valve leaflet with (n = 6) or without (n = 2) prior cultured cell seeding. The animals were killed either after 6 hours or after 1, 6, 7, 9, or 11 weeks, and the implanted valve leaflets were examined histologically, biochemically, and biomechanically. 4-Hydroxyproline assays were performed to determine collagen content. Leaflet strength was evaluated in vitro with a mechanical tester Factor VIII and elastin stains were done to verify histologically that endothelial cells and elastin, respectively, were present. Animals receiving leaflets made from polymers without cell seeding were killed and examined in a similar fashion after 8 weeks. In the control animals, the acellular polymer leaflets were completely degraded, with no residual leaflet tissue at 8 weeks. The tissue-engineered valve leaflet persisted in each animal in the experimental group. 4-Hydroxyproline analysis of the constructs showed a progressive increase in collagen content. Immunohistochemical staining demonstrated elastin fibers in the matrix and factor VIII on the surface of the leaflet. The cell-labeling experiments demonstrated that the cells on the leaflets had persisted from the in vitro seeding of the leaflets. CONCLUSIONS: In the tissue-engineered heart valve leaflet, transplanted autologous cells generated a proper matrix on the polymer scaffold in a physiological environment at a period of 8 weeks after implantation.

Animals↗
PubMed1996

[The failing heart valve. History of the Björk-Shiley convex-concave heart valve].

Strut fracture with embolization of the valve disk has been reported worldwide in about 550 cases out of a total of 86,000 implanted Björk-Shiley convexo-concave disk valves. 320 of the patients died. In Norway six cases of strut fracture are reported, with five deaths. The highest risk is reported for valves with a 70 degree opening of the disk. Other risk factors are large valves in the mitral position, valves produced in the year 1981 and early 1982, and valves welded by inexperienced welders. A joint lawsuit which was started in January 1992 on behalf of all living patients with a CC-valve has been concluded and has resulted in a legal settlement between the parties.

Heart Valve Prosthesis↗
PubMed1991

Multiple floppy valves with all cardiac valves prolapsing: clinical course and treatment.

Two cases with prolapse of all four cardiac valves are described and compared with two similar ones previously reported. The severity and progression of regurgitation of each of the valves differed by case, despite having similar echocardiographic findings consistent with the diagnosis of multiple floppy valves. Two of the four patients had their aortic valve replaced because of severe regurgitation: the excised valves revealed myxomatous degeneration. None of the patients had any stigmata of Marfan or Ehlers-Danlos syndrome, except for the presence of hyperextensive joints. There may be an unknown collagen disorder that caused floppiness in all the valves.

Adolescent↗
PubMed2000

Evaluation of postoperative cardiac function and long-term results in patients after aortic valve replacement for aortic valve disease with increased left ventricular mass.

OBJECTIVE: This clinical study was designed to evaluate the postoperative cardiac function in patients after aortic valve replacement for aortic valve disease with increased left ventricular mass. METHODS: Aortic valve replacement was performed in 117 patients using the St. Jude Medical valve. Their valve lesion was aortic regurgitation in 71, and aortic stenosis in 46. The mean value of the left ventricular mass index was 272 g/m2. The 117 patients were subdivided into 4 groups according to their preoperative left ventricular mass index-Group I (n = 35) with aortic regurgitation and a large left ventricular mass index (> or = 273 g/m2), Group II (n = 36) with aortic regurgitation and a small left ventricular mass index Group III (n = 19) with aortic stenosis and a large left ventricular mass index, and Group IV (n = 27) with aortic stenosis and a small left ventricular mass index. The cardiac function was evaluated by radionuclide ventriculography. RESULTS: In a comparative study of postoperative parameters among the 4 groups, the postoperative systolic and diastolic parameters of Group I patients were more significantly impaired compared with these parameters of the other 3 groups. The postoperative values the left ventricular mass index were significantly higher in Group I than in the other 3 groups. The 10-year survival rate was significantly lower in Group I than in the other 3 groups (30 +/- 22% in Group I). CONCLUSION: Aortic valve replacement is recommended for patients with eccentric hypertrophy in the adequate clinical phase of patients whose left ventricular mass index is less than 272 g/m2.

Adult↗