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At least 811 records · Page 45Linked to original sources
PubMed2000

Mid-term results of the valve-on-valve technique for bioprosthetic failure.

OBJECTIVE: Redo operations for bioprosthesis malfunction can sometimes be technically very demanding and cardiac structures may be damaged. Excising only the leaflets of the damaged bioprosthesis and leaving the old ring in situ on which the 'new' mechanical valve is sutured can, in very selected cases, represent a solution. METHODS: Twenty-two patients were operated on, with the valve-on-valve technique, from September 1991 through December 1992. There were three operative deaths. RESULTS: The surviving 19 patients were followed-up from 83 to 98 months (mean 90.5 months.). There were two late deaths. The patients were examined clinically and with transthoracic and transesophageal echocardiograms. All patients were in good condition and the echocardiographic examinations showed no clinically important gradients across the prostheses. CONCLUSIONS: The valve-on-valve technique, in certain difficult situations, can give successful mid-term results.

Adult↗
PubMed2000

Long-term follow-up of morbidity and mortality after aortic valve replacement with a mechanical valve prosthesis.

AIMS: The aim of this study was to determine the incidence of valve-related complications in patients with a mechanical aortic valve prosthesis and to identify risk factors for an adverse outcome. METHODS AND RESULTS: In the 424 patients, event-free survival rates 5 and 10 years after aortic valve replacement were 62% and 37%, respectively. The linearized incidence of thromboembolic events was 4.4% per patient-year, and of anticoagulant-related haemorrhage 8.5% per patient-year. Advanced NYHA functional class, atrial fibrillation, pure aortic regurgitation and thromboembolism prior to surgery decreased event-free survival. A history of pre-operative thromboembolism increased the risk for a first embolic event after aortic valve replacement (relative hazard [RH] 3.2), but was even more strongly associated with the risk for repeated events (> or =2 events, RH 5.4). After each thromboembolic episode that occurred, the risk for a subsequent one was increased. The risk for at least one, and up to three or more haemorrhages was increased in patients with a pre-operative history of bleeding (RH 3.3-5.1) and of atrial fibrillation (RH 1.8-3.9). The risk for a subsequent event was increased by a history of repeated haemorrhages, a short interval since previous bleeding, and high age. CONCLUSIONS: There were few factors strongly related to valve related morbidity. However, previous bleedings and previous thromboembolism were powerful risk factors for repeated events.

Adolescent↗
PubMed1979

Combined aortic and mitral valve replacement. A randomized study comparing the Björk-Shiley and Lillehei-Kaster disc valve.

The present series was comprised of 48 patients, 25 of whom received the Björk-Shiley (B-S) and 23 the Lillehei-Kaster (L-K) disc valves. The 2 groups were comparable with regard to age, and to preoperative clinical and hemodynamic status. The randomized selection was carried out at the beginning of the operation. The total mortality in the B-S and L-K groups was 16% and 21% respectively. All surviving patients were restudied 13-40 months (mean 27) after surgery. Late thromboembolic complications occurred in 2 patients with B-S and in 3 with L-K valves, all leaving minor neurological sequelae. There was a relatively large number of patients in the L-K group with unmeasurable values of haptoglobin, indicating more hemolysis in these patients. However, the difference was not statistically significant. The clinical and hemodynamic status was improved in both groups. In the aortic position a significant gradient was found across the L-K valve, while no significant obstruction in the flow was found in the B-S valve. The pulmonary arteriolar resistance was significantly higher in patients with B-S than in those with L-K valves. Otherwise, there was no significant differences between the 2 groups, neither with regard to clinical nor to hemodynamic status.

Aortic Valve↗
PubMed1983

Left ventricular response to isometric exercise in aortic valve diseases and its value in the optimal timing of aortic valve replacement.

In order to evaluate the left ventricular response to isometric exercise in different types of aortic valve disease, isometric exercise tests were performed during cardiac catheterization in 14 patients with pure aortic stenosis, 20 with combined aortic stenosis and regurgitation, and 18 with pure aortic regurgitation. Patients with angina pectoris in whom coronary angiography had not been performed were excluded. Thirty-seven patients were recatheterized 12 months after aortic valve replacement, and the ventricular response to exercise was re-evaluated. Preoperatively, the ejection fraction did not change significantly during exercise in patients with aortic stenosis, tended to decrease in patients with combined valve lesion, and decreased significantly in patients with aortic regurgitation (p less than 0.001). In the three patients whose ejection fraction during preoperative exercise decreased to below 0.40, it remained below 0.50 after successful aortic valve replacement. It appears possible to reveal left ventricular dysfunction in many patients with aortic regurgitation and in some with combined aortic valve disease by means of isometric exercise. The severely depressed ventricular dysfunction during exercise does not appear to correct totally after surgery.

Adult↗
PubMed1975

Cardiac valve replacement with the stabilized glutaraldehyde porcine aortic valve: indications, operative results, and followup.

Porcine aortic valve xenografts stabilized with glutaraldehyde have been implanted in 91 patients with acquired and congenital valvular heart disease. The indications for use of this valve have included age, previous sensitivity to anticoagulants, or a concomitant condition contraindicating anticoagulant therapy. There were two operative deaths and three late deaths in 44 mitral, 25 aortic, 16 aortic-mitral, 5 mitral-tricuspid, and one aortic-mitral-tricuspid replacements. There were no valve failures from cusp rupture, although one valve was replaced because of annular disproportion. There was one inhospital stroke but no late emboli in a 3 to 33 month followup period, 16.5; 72 patients are functional class 1, 10 class 2, and one patient is class 3. In appropriate patients this biologic tissue valve relieves the hemodynamic abnormalities of valvular heart disease, is associated with a low embolization rate without anticoagulant therapy and, to date, has been durable.

Adolescent↗
PubMed1976

Long-term survival after isolated replacement of mitral valve with ball-valve prosthesis.

In 111 patients whose diseases mitral valve was replaced with a ball-valve prosthesis the actuarial survival rate, including the hospital mortality of 10.8%, was 66% after 5 years and 59% after 8 years of follow-up. This suggests that in patients with moderate or severe symptoms due to mitral valve disease, replacing the valve can prolong life. However, in patients with no cardiac symptoms or with sinus rhythm and mild symptoms, it is doubtful that mitral valve replacement can prolong life, for the prognosis in these patients is favourable without operation.

Female↗
PubMed2003

[Hemolytic anemia due to aortic valve regurgitation after mitral valve replacement].

A 50-year-old woman was admitted to our hospital because of heart failure (NYHA III) due to mitral valve regurgitation (MR) with pulmonary hypertension (PH) and tricuspid valve regurgitation (TR). She had a history of chronic renal failure undergoing dialysis (peritoneal dialysis, homodialysis) since 1996. Cardiac catheterization and ultrasonic cardiography showed severe MR (Sellers III), severe TR and PH (mean pressure 33 mmHg). So we performed mitral valve replacement and tricuspid annuloplasty (DeVega). Frequent blood transfusion was needed because severe hemolytic anemia appeared after operation. Ultrasonic cardiography demonstrated moderate aortic valve regurgitation (AR) with no paravalvular prosthetic leakage. We diagnosed hemolytic anemia due to AR. We performed aortic valve replacement. Hemolytic anemia improved soon after second operation. We investigated the mechanical process of the AR. She had a very short subaortic curtain (5.9 mm) compared with the average (8.7 +/- 2.1 mm: mean +/- SD) of cardiac patients. We think that we must be very careful with suture to short subaortic curtain. In addition measurement of subaortic curtain before operation is very useful.

Anemia, Hemolytic↗
PubMed1988

[Calcinosis of the mitral valve system and its effect on valve function. A Doppler echocardiography study].

Non-inflammatory calcific disease of the mitral valve apparatus is a common finding in elderly patients. This study describes the incidence, clinical findings and location of mitral calcium deposits detected by 2D-echocardiography in an unselected series of patients referred for echocardiography to a general hospital. In addition, valvular function was assessed by Doppler sonography. In 48 out of 217 consecutive patients, 2D-echocardiography showed mitral calcium deposits. The mean age of this patient group was 72 +/- 11 years. Clinical histories and findings in most patients indicated an association between calcium deposits and increased tension of valve structures by left ventricular pressure overload (i.e., hypertension, aortic stenosis), dilatative cardiomyopathy or valve prolapse. Calcific deposits were located predominantly at the posterior mitral ring, but in 48% of our patients calcification of mitral chordae was also seen. Mitral regurgitation was detected by Doppler sonography in 52% of the patient group, in 25% at least moderate mitral regurgitation could be demonstrated. The presence of valve incompetence was not dependent on the location of calcium deposits. Mitral valve area, as assessed by Doppler, ranged from 2.1 to 6.7 cm2.

Aged↗
PubMed1987

Asynchronous primary valve failure in patients with porcine bioprosthetic aortic and mitral valves.

Seventy-three patients with aortic and mitral porcine bioprosthetic valves (PBV) have been followed for up to 14 1/2 years. In that time, 11 patients have undergone replacement of one or more PBVs for primary tissue failure. Three patients underwent repeat aortic and mitral valve replacement for synchronous PBV failure. Two patients underwent aortic valve replacement alone and six had only the mitral PBV replaced. The one survivor of the repeat aortic valve replacement has a normally functioning mitral PBV, which has now been in place for 48 months. The six patients who had their mitral PBVs replaced have normally functioning aortic PBVs that have now been in place for periods from 96 to 176 months. Our experience shows that with asynchronous PBV failure only the dysfunctioning valve needs to be replaced. Prophylactic PBV replacement is not warranted if the prosthesis demonstrates normal hemodynamics on cardiac catheterization and normal structure on the echocardiogram, regardless of the length of time it has been implanted.

Actuarial Analysis↗
PubMed1984

[Results of singular valve replacement with a mechanical prosthesis or bioprosthesis in valve diseases with advanced myocardial failure].

Surgery may prolong survival in some patients in advanced cardiac failure due to valvular heart disease refractory to digitalo-diuretic and vasodilator therapy. The operative risk is high and myocardial dysfunction after surgery is also a problem. However, in some cases, surprising improvement is observed. An analysis of the principal publications in the literature on the natural history of valvular heart disease and the results of surgery in the last ten years show that: In chronic aortic valve disease complicated by congestive heart failure, the natural prognosis does not exceed 2 to 3 years in either aortic stenosis or regurgitation. On the other hand, prosthetic valve replacement is associated with a 57% 4 years survival in aortic regurgitation, and a 70% 5 years survival in aortic stenosis, but with an operative mortality of 20 to 27%. Surgery is even more valuable in acute aortic regurgitation due to endocarditis, leading to a 60% 2 years survival compared to only 6% with medical therapy alone. In chronic mitral valve disease with advanced cardiac failure, the natural prognosis does not exceed 4.5 years in mitral regurgitation, 8 years in mitral stenosis and an intermediate period in mixed mitral valve disease. On the other hand, prosthetic valve replacement with an operative risk of 21 to 26% is associated with a life expectancy of 56 to 60% at 5 years, and 46% at 10 years, operative mortality included. The surgical results depend on good myocardial protection and intensive pre-, per- and post-operative care using positive inotropic agents, vasodilators and, when necessary, intra aortic balloon pumping.(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic Valve↗
PubMed1980

Repeated mitral valve replacement in the growing child with congenital mitral valve disease.

The successful second-replacement of mitral valve prostheses in two children, age 5 and 9 years, is reported. In one, a parachute mitral valve deformity was first corrected at the age of 10 months by the small-size 00 Starr-Edwards prosthesis. The second child had mitral valve disease caused by Marfan's syndrome 1; the valve was initially replaced at the age of 3 years by a size 0 Starr-Edwards prosthesis. For both patients, in the period between the two interventions, the left ventricle had grown in size and the mitral anulus was not a limiting factor in the insertion of a larger prosthesis of the Björk-Shiley type. Follow-up periods of 1 and 6 years, respectively, confirm excellent clinical results. Problems concerning valve replacements in pediatric patients are discussed.

Child↗
PubMed1995

[Isolated aortic valve regurgitation due to degeneration of the valve leaflet--a clinical study].

From 1989 through 1993 thirty-eight patients underwent aortic valve replacement at our institution for isolated aortic regurgitation (AR) caused by idiopathic degeneration of the valve. There were 32 male and 6 female patients aged between 33 and 74 years with a mean of 59 years. Preoperative New York Heart Association functional class, cardiothoracic ratio, cardiac index, and left ventricular end-diastolic pressure were 2.6, 57%, 3.1 L/min/m2, and 18 mmHg, respectively. Cross-sectional echocardiography clarified aortic valve prolapse in seven patients. Excised valvular cusps were thin, redundant and translucent in association with cuspal fenestration in 9 cases and idiopathic commissural disruption in 2 cases. Histological study revealed significant disruption of the fibrosa and cystic degeneration of the spongiosa layer filled with mucopolysaccharide. Actuarial survival rate, including 3 operative deaths, was 89% at 3 years after AVR with no apparent valve related complications. Idiopathic degeneration of the aortic valve is a common cause of AR, occurring in half of the surgically treated patients. We emphasize the importance of this lesion as a cause of AR.

Adult↗
PubMed1996

[Report of a case with re-mitral valve replacement for Björk-Shiley Delrin disc valve prosthesis--disc wear of the Delrin disc 20 years after implantation].

We reported a patient in whom slight congestive heart failure gradually developed 20 years after mitral valve replacement with a Delrin disc Björk-Shiley valve prosthesis. Although no evident cause of prosthetic valve malfunction could be detected preoperatively, the mitral prosthesis was excised and replaced uneventfully with a 29 mm St. Jude Medical valve prosthesis. At gross inspection, marked wears of the Delrin disc surface and strut shaped indentations were present. These disc variance, occurred much earlier than initially predicted by Dr. Björk, allowed prosthetic valve malfunction. The patient with this specific model should be carefully followed-up, if necessary, performed reoperation.

Heart Valve Prosthesis↗
PubMed1986

Tricuspid valve Candida endocarditis. Successful treatment with valve-sparing debridement and antifungal chemotherapy in a multiorgan transplant recipient.

Tricuspid valve Candida albicans endocarditis developed in a multiple-organ transplant recipient six months after successful treatment of Candida peritonitis. She has had no recurrence or valvular incompetence two years after valve-sparing debridement of the vegetation and prolonged therapy with amphotericin B. This is the second report of long-term success following valve-sparing debridement for tricuspid valve Candida endocarditis. In selected patients without annular involvement or gross valve destruction, excision of the fungal vegetation may allow for long-term cure and a competent valve.

Adult↗
PubMed2005

CD34+ fibrocytes in normal mitral valves and myxomatous mitral valve degeneration.

We investigated a total of 15 mitral valves with myxomatous degeneration and compared these with normal mitral valves. In normal mitral valves, stromal cells located in the fibrosa and spongiosa showed small bipolar cytoplasmic processes and were found to be positive for CD34, suggesting a close relationship to CD34+ fibrocytes. In cases of myxomatous degeneration, stromal cells showed an altered morphology in that they exhibited multipolar cytoplasmic processes, appeared to be hyperplastic, and were increased in number. This study is the first to report on CD34+ fibrocytes making up the majority of mitral valve stromal cells. Major factors in the development of myxomatous valve degeneration are MMP-9, as well as collagen I and III, which have been reported to be secreted by CD34+ fibrocytes. Therefore, it is likely that CD34+ fibrocytes are involved in the pathogenesis of myxomatous mitral valve degeneration.

Adult↗
PubMed2002

Aortic valve reimplantation in ascending aortic aneurysm: risk factors for early valve failure.

BACKGROUND: Aortic root reconstruction by reimplantation of the native valve represents a new therapeutic option for ascending aortic aneurysms. Information about long-term follow-up is limited, and possible predictors for failure of reconstruction have not been evaluated so far. METHODS: After aortic valve reimplantation 101 patients were followed in a prospective observational study. From this cohort the first 75 consecutive patients with a complete 1-year follow-up were chosen for further analysis. Clinical and echocardiographic data were obtained preoperatively, intraoperatively, and early postoperatively, as well as after 1 year of follow-up. RESULTS: No mortality was observed within the first 30 days. There were 52 male patients, mean age was 49.1+/-20.6 years, observation period was 35.6+/-20.6 months, and Marfan's syndrome was present in 22 patients. Although in 67 patients a stable valve function could be demonstrated, 5 patients presented with mild aortic insufficiency or had to be operated on again for secondary valve failure (n = 3). Analyzing possible demographic, disease-related, and procedure-related risk factors in a multivariable approach, only level of coaptation within the graft (as assessed by echocardiography) could be identified as being related to the subsequent development of aortic insufficiency. Coaptation level within the tube graft (type A) resulted in a mean aortic regurgitation grade of 0.3+/-0.5 as compared with a mean grade of 2.5+/-0.6 for a coaptation type C (below the prosthesis; p < 0.001). CONCLUSIONS: Aortic valve reimplantation is a promising alternative to alloprosthetic composite replacement. A level of coaptation within the tube graft is essential to achieve valve competence.

Adolescent↗
PubMed1984

An experimental model of a submucosally tunnelled valve for the replacement of the ileo-cecal valve.

An enteric valve to prevent colonic content reflux and to prolong small bowel transit time was created by passing small bowel through a submucosal tunnel in the colon. Barium enema, Gl tract series, and iso- and antiperistaltic pressure measurements showed the valve to be of competence equal to the ileo-cecal valve. Late pathological examination revealed a patent valve with minimal scar formation. The optimal submucosal tunnel length was between 4 and 6 cm. This valve can, theoretically, increase the absorptive capacity in short bowel syndrome and may serve as a substitute for the critically important ileo-cecal valve.

Animals↗
PubMed1985

Anatomic analysis of removed prosthetic heart valves: causes of failure of 33 mechanical valves and 58 bioprostheses, 1980 to 1983.

The details of heart valve prosthesis-associated problems are not widely known. This study investigated the etiologies of the failures of 91 valves, 33 mechanical prostheses and 58 bioprostheses, obtained at reoperation (83) or autopsy (eight) at the Brigham and Women's Hospital during the 42-month period from mid- 1980 through 1983, one to 264 months (mean, 72 months) after valve replacement. Analysis was by gross, histologic, radiographic, and microbiologic examination, as well as review of clinical records. Overall causes of failure included paravalvular leak (15 per cent), thrombosis (7 per cent), tissue overgrowth (8 per cent), degeneration or mechanical failure (43 per cent), and endocarditis (19 per cent). Endocarditis and paravalvular leak were equally frequent with mechanical prostheses and bioprostheses. In addition, thrombosis (18 per cent), tissue overgrowth (21 per cent), and structural failure (12 per cent) were all important failure modes for mechanical prostheses. Sterile degeneration was the overwhelming cause of failure for bioprostheses, accounting for the failure of 35 of 58 (60 per cent) of those recovered. Sterile degeneration took several forms: calcification, with or without cuspal tears (27 cases, 47 per cent of bioprostheses; mean, 77 months, range, 44 to 108 months) and cuspal defects without calcification (eight cases, 14 per cent; mean, 59 months, range, eight to 122 months). In general, calcification increased with time after implantation, but the propensity for the mineralization of bioprostheses varied widely among patients. Four torn valves that had been in place for more than six years had radiographically undetectable calcific deposits. The results of this study indicate that paravalvular leak and endocarditis are frequent causes of failure for all valve types. No clear failure mode predominates with mechanical valve prostheses, although some designs have specific inherent limitations. In contrast, degeneration, especially that related to mineralization, is the most important cause of the late failure of contemporary bioprostheses.

Adolescent↗