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At least 55 records · Page 3Linked to original sources
PubMed2001

Triple valve replacement with bileaflet mechanical valves: is the mechanical valve the proper choice for the tricuspid position?

A more durable mechanical valve may be a better choice for the tricuspid position than a bioprosthesis when the patient already has mechanical prosthesis in the left side of the heart. Eleven cases of triple valve replacement (total follow-up period, 49.5 patient years), all with mechanical valves, are reviewed to assess optimal valve selection. Nine patients had undergone a total of 12 previous cardiac surgeries. Three patients died in hospital (27.3%), but there were no late deaths among the survivors. Two cases of valve thrombosis in the tricuspid position occurred (linearized incidence: 4.04%/patient years) and 1 of these required reoperation. Because of this high incidence of valve thrombosis, the bileaflet mechanical valve is not considered to be the best choice. Even if mechanical valves are implanted in the left side of the heart, a bioprosthesis may be a better choice at the tricuspid position.

Adult↗
PubMed1986

[Surgical indications in mitral valve stenosis, combined mitral valve defect or mitral valve insufficiency. Long-term prognosis of operated or drug-treated patients].

Data obtained from 683 patients with mitral valve disease, NYHA-class III or IV, were retrospectively studied by means of a multivariate Cox regression analysis. Based on symptoms and hemodynamic findings, surgical intervention had been recommended for all patients: closed mitral commissurotomy (n = 361), prosthetic mitral valve replacement (n = 241) and prosthetic mitral valve replacement together with a corrective procedure for the tricuspid valve (n = 81). While the majority of patients underwent surgery during the observation period (n = 528), a substantial number of patients continued on medical treatment (n = 155). The mean observation periods were 52, 49 and 31 months, respectively, in the three collectives. Surgically treated patients in whom closed mitral commissurotomy had been recommended had a better prognosis (p less than 0.0003) than those treated medically (five-year survival rate 89% vs. 63%). Age, clinical severity, previous mitral commissurotomy, pulmonary vascular resistance and right atrial mean pressure had no significant influence on prognosis. In patients in whom prosthetic mitral valve replacement had been recommended, surgical treatment led only to tendencial improvement in prognosis as compared with those treated medically (five-year survival rate 78% vs. 61%). Factors with an unfavorable influence on prognosis were age more than 49 years (p less than 0.05), pure mitral regurgitation (p less than 0.001), NYHA-class IV (p less than 0.02) and right atrial mean pressure in excess of 4 mm Hg (p less than 0.01). In patients in whom prosthetic mitral valve replacement together with a corrective procedure for the tricuspid valve had been considered necessary, surgical treatment had no significant influence on prognosis as compared with those treated medically (five-year survival rate 57% vs. 53%). Patients in whom previous mitral commissurotomy had been performed had an extremely poor prognosis (p less than 0.001). Pulmonary vascular resistance was significantly reduced both after mitral commissurotomy as well as after prosthetic mitral valve replacement; this was associated with a significant decrease in right atrial mean pressure and increase in right ventricular ejection fraction. The indication for closed mitral commissurotomy, thus, appears established in patients with symptoms of class III or IV clinical severity. The indication can be established generously since the surgical mortality is low and long-term prognosis is good.(ABSTRACT TRUNCATED AT 400 WORDS)

Anti-Bacterial Agents↗
PubMed1997

Microbiological cultures of heart valves and valve tags are not valuable for patients without infective endocarditis who are undergoing valve replacement.

We evaluated the significance of the results of microbiological cultures of heart valves and identification tags from newly inserted prosthetic valves that were removed from patients with valvular heart disease; none of these patients had a preoperative diagnosis of endocarditis. We reviewed the charts of patients with positive cultures for evidence of infections before or after surgery. Cultures were positive for 11.9% of 219 valves (206 native valves and 13 prosthetic or bioprosthetic valves) and 11.6% of 224 tags. The most common isolates were coagulase-negative staphylococci. Typical agents of endocarditis--viridans streptococcus, Enterococcus faecalis, and Staphylococcus aureus--were cultured from five specimens, and Mycobacterium avium complex was identified in six valves. None of the patients with positive valve or tag cultures developed postsurgical endocarditis or wound infection. Findings on histopathologic examination of the valves were not consistent with endocarditis. We conclude that the results of cultures of valves from patients without preoperative diagnoses of endocarditis lack clinical significance, and positive tag cultures are not predictive of postsurgical infection. Positive cultures are most likely a result of contamination during surgery or thereafter.

Adolescent↗
PubMed2003

Durability and outcome of aortic valve replacement with mitral valve repair versus double valve replacement.

BACKGROUND: The purpose of this study was to evaluate morbidity and mortality after double valve replacement (DVR) and aortic valve replacement with mitral valve repair (AVR + MVP). METHODS: From 1977 to 2000, 379 patients underwent DVR (n = 299) or AVR + MVP (n = 80). Actuarial survival and freedom from reoperation were determined by the Kaplan-Meier method. Potential predictors of mortality and reoperation were entered into a Cox multiple regression model. Propensity score was introduced for the multivariable regression modeling for adjustment of a selection bias. RESULTS: Survival 15 years after surgery was similar between the groups (DVR, 81% +/- 3%; AVR + MVP, 79% +/- 7%; p = 0.44). Freedom from thromboembolic event at 15 years was similar between the groups (p = 0.25). Freedom from mitral valve reoperation at 15 years was significantly better for the DVR group (54% +/- 5%) as compared with the AVR + MVP group (15% +/- 6%; p = 0.0006), primarily due to progression of mitral valve pathology and early structural deterioration of bioprosthetic aortic valve used for patients with AVR + MVP. After AVR + MVP, freedom from mitral reoperation at 15 years was 63% +/- 16% for nonrheumatic heart diseases, and 5% +/- 5% for rheumatic disease (p = 0.04). CONCLUSIONS: Although both DVR and AVR + MVP provided excellent survival, DVR with mechanical valves should be the procedure of choice for the majority of patients because of lower incidence of valve failure and similar rate of thromboembolic complications compared with AVR + MVP. MVP should not be performed in patients with rheumatic disease because of higher incidence of late failure.

Actuarial Analysis↗
PubMed2005

Complex aortic valve repair as a durable and effective alternative to valve replacement in children with aortic valve disease.

OBJECTIVE: This study was undertaken to determine the utility of aortic valve repair in children. METHODS: A retrospective analysis was conducted on aortic valve surgery from 1973 to 2004 at Children's Hospital of Wisconsin. RESULTS: Procedures were classified as simple repairs (blunt valvotomy, commissurotomy with or without thinning, n = 147), repair of aortic insufficiency with ventricular septal defect (n = 22), complex repairs (any combination of additional procedures including suspension of prolapsed leaflets, leaflet extensions, repair of torn or perforated leaflets, annuloplasty, reduction of sinus of Valsalva plasty, and concomitant repair of supravalvular or subvalvular stenosis, n = 57), and replacements (n = 57, 20 mechanical, 2 porcine, and 35 human valves). Freedoms from reintervention for simple repairs and repair of aortic insufficiency with ventricular septal defect at 10 years were 86% +/- 5% and 93.3% +/- 6%, respectively. For complex valve repair, freedoms from reintervention at 1, 5, and 10 years were 94% +/- 3%, 85% +/- 6%, and 44% +/- 15%, versus 96% +/- 3%, 77% +/- 9%, and 77% +/- 9% for valve replacement ( P = .3). At intermediate follow-up, patients with complex valve repair had a residual gradient of 20 +/- 21 mm Hg, and 94% were free of severe aortic insufficiency. Residual aortic stenosis ( P < .05) but not the preoperative diagnosis of combined aortic stenosis and insufficiency predicted the need for reintervention. CONCLUSION: Freedom from reintervention after complex valve repairs was not different from that after valve replacement, with acceptable residual aortic stenosis and insufficiency. Simple repairs and repair of aortic insufficiency with ventricular septal defect yielded excellent long-term freedom from reintervention.

Adolescent↗
PubMed2005

Influence of angiotensin-converting enzyme gene insertion/deletion polymorphism on rheumatic valve involvement, valve severity and subsequent valve calcification.

BACKGROUND AND AIM OF THE STUDY: The relationship between the severity of chronic rheumatic heart disease (RHD) and predisposing factors is unknown, and genetic predictors for severe scarring and calcification of the mitral valve are not well defined. A high angiotensin-converting enzyme (ACE) activity has been demonstrated in valve tissue. Thus, a case-control study was conducted to investigate any possible relationship between ACE gene polymorphisms and chronic mitral valve disease severity and calcification. METHODS: This case-control study included 82 patients (24 males, 58 females; mean age 40.3 +/- 14.7 years) with chronic rheumatic mitral valve, and 154 control subjects (53 males, 101 females; mean age 43.4 +/- 13.4 years). ACE gene insertion/deletion (I/D) polymorphisms were identified using polymerase chain reaction methods. RESULTS: Among RHD subjects, 31 (30.6%) were D/D, 25 (32.7%) were I/D, and 26 (18.8%) were I/I. Among controls, 57 (57.4%) were D/D, 69 (61.3%) were I/D, and 28 (35.2%) were I/I. The frequency of ACE I/I genotype was higher in RHD subjects than in controls (chi2 = 7.4, df = 2, p < 0.030; D/D versus I/D versus I/I), or (chi2 = 5.5, df = 1, p < 0.019; DD + ID versus II). Predisposition to RHD was significantly less frequent in the D/D genotype. There was no statistically significant difference in the genetic analysis of RHD with respect to mitral valve score, severity of mitral regurgitation and left atrial diameter. Mitral valve calcification was significantly associated with a higher frequency of I/I genotype and I/D genotype than D/D genotype alone (chi2 = 6.2, df = 2, p = 0.043). The ACE I/I genotype was associated with a predisposition to a greater risk of severe calcific valve disease. CONCLUSION: The ACE I/I genotype is more common in patients with rheumatic valve disease than in the normal population. This suggests that the ACE gene polymorphism may be involved in the pathogenesis of rheumatic heart disease.

Adolescent↗
PubMed2005

Re-do mitral valve replacement using the valve-on-valve technique: a case report.

We report a repeated mitral valve replacement (re-do MVR) using the valve-on-valve technique for a degenerated bioprosthesis. A 49-year-old female, who had had a 29 mm Carpentier-Edwards mitral bioprosthesis for mitral regurgitation 20 years previously, was referred to our institution for dyspnea. She presented with pulmonary edema secondary to severe mitral bioprosthetic valve regurgitation. We replaced the degenerated mitral bioprosthesis with a 25 mm mechanical prosthesis using the valve-on-valve technique, as the struts of the bioprosthesis were embedded in the left ventricular myocardium. Removal of the bioprosthesis may be not only time-consuming but also complicated by cardiac rupture at the atrioventricular junction or the posterior left ventricular wall. The valve-on-valve technique is a simplified procedure that can avoid the potential complications of complete excision of the bioprosthesis. We believe this technique can be a useful strategy for patients with a degenerated mitral bioprosthesis.

Bioprosthesis↗
PubMed1995

[Enlargement of the aortic and mitral double valve rings with double valve replacement using coupling valve method].

A 46-year-old woman was hospitalized with congestive heart failure. She had undergone a mitral valve replacement (23 mm) 17 years earlier and complicated a left ventricular rupture. Upon admission, she was diagnosed with aortic and mitral stenoinsufficiency with narrowed annuli on both valves, tricuspid insufficiency, and a left ventricular pseudoaneurysm. The operative procedure consisted of enlarging the aortic and mitral valve rings and replacing them by the coupling valve method. The orifice of the pseudoaneurysm was repaired with a patch closure applied from the endocardial side. A tricuspid annuloplasty was performed using the DeVega's method. Her postoperative course was uneventful. This is the first report of a successful operation to correct double narrowed annuli along with a ruptured left ventricule. The coupling valve procedure employed here should prove useful for similar cases requiring enlargement and replacement of the aortic and mitral valves simultaneously.

Aneurysm, False↗
PubMed2005

Flow-induced platelet activation in a St. Jude mechanical heart valve, a trileaflet polymeric heart valve, and a St. Jude tissue valve.

Polymer heart valves have been under investigation since the 1960s, but their success has been hampered by an overall lack of durability mainly due to calcification of the leaflets and a relatively high rate of thromboembolic complications. A new polymer (Quatromer) trileaflet design was tested for its thrombogenic potential and was compared to that of existing prosthetic heart valves routinely implanted in patients: a St. Jude Medical bileaflet mechanical heart valve (MHV) and a St. Jude porcine bioprosthetic tissue valve. The valves were mounted in a left ventricular assist device and the procoagulant activity of the platelets was measured using a platelet activation state (PAS) assay. The PAS measurements indicated that the platelet activation level induced by the polymeric valve was very similar to that induced by the St. Jude Medical MHV and the St. Jude tissue valve. No significant difference was observed between the three valves, indicating that they have a comparable thrombogenic potential.

Bioprosthesis↗
PubMed1984

The risk of thromboembolism and hemorrhage following mitral valve replacement. A comparative analysis between the porcine xenograft valve and Ionescu-Shiley bovine pericardial valve.

To ascertain the risk of thromboembolism and anticoagulant-related hemorrhage following mitral valve replacement with bioprostheses, an 8 year retrospective study between two groups of patients was analyzed. Group I included 206 patients undergoing mitral valve replacement with porcine xenograft valves. They were placed on a regimen of long-term oral anticoagulation (greater than 8 weeks, mean 6 months). Follow-up was 524.3 patient-years, mean 30.5 months. There were 24 thromboembolic events (4.6% per patient-year), four of which were fatal. Actuarially, 80.7% +/- 4.3% are free of thromboembolism at 8 years. There were 12 instances of major bleeding episodes, for a linearized incidence of 2.5% per patient-year; two were fatal. Group II included 322 patients undergoing mitral valve replacement with a bovine pericardial valve. They were placed on a program of short-term anticoagulation (6 weeks only). Follow-up was 1,106 patient-years, mean 46.4 months. There were four thromboembolic episodes (none fatal), an incidence of 0.36% per patient-year. Seven bleeding episodes occurred, 0.63% per patient-year; none was fatal. The difference between the groups reached statistical significance (p less than 0.001). The low risk of thromboembolism with the bovine pericardial valve appears to be due to its superior hydraulic characteristics. Use of this valve allows mitral valve replacement without long-term oral anticoagulation and the associated risk of anticoagulant-related hemorrhage.

Adolescent↗
PubMed1996

Predictive value of prosthetic valve area index for early and late clinical results after valve replacement with the St Jude Medical valve prosthesis.

BACKGROUND: Previous studies indicate that a minimal prosthetic valve area index (VAI) of > or = 0.9 cm2/m2 for aortic and > or = 1.3 cm2/m2 for mitral valves minimizes postoperative pressure gradients. METHODS AND RESULTS: To determine VAI as an independent risk factor for postoperative events, 607 isolated aortic valve replacement (AVR) and 482 isolated mitral valve replacement (MVR) operations with the St Jude Medical valve were studied. End points included hospital deaths, NYHA functional class, late death and late valve-related death, major thromboembolism, anticoagulant-related hemorrhage, and reoperation. VAI was calculated from the ratio of prosthetic valve area to body surface area for each patient, and a range and mean were obtained for each valve size. Follow-up ranged from 1 to 120 months, totaled 2964 patient-years, and was 98% complete. Mean and range of VAI (cm2/m2) were 1.31 (0.74 to 2.86) in the aortic and 2.5 (1.4 to 6.32) in the mitral group. There were 33 AVR (5.4%) and 38 MVR (7.9%) hospital deaths. VAI was not a risk factor for NYHA class, early death, late death, or other postoperative events. The actuarial survival rates, 84% for AVR and 80% for MVR at 5 years, were not affected by VAI. CONCLUSIONS: Within the ranges measured, VAI did not influence the end points of the study.

Adolescent↗
PubMed2005

Successful valve repair for congenital bicuspid aortic valve and degenerated prolapsed mitral valve.

A 54-year-old man with congenital bicuspid aortic valve underwent simultaneous valve repair for aortic and mitral regurgitation. Surgical technique consisted of plication of redundant aortic valve repair and mitral annuloplasty with chordal replacement. One-year follow-up transthoracic echocardiography showed no valve regurgitation. Valve repair for both bicuspid aortic valve and mitral valve regurgitation should be the first option in this subset of patients.

Aortic Valve↗
PubMed1983

[Effect of valve type and valve function on chronic intravascular hemolysis after alloprosthetic mitral and aortic valve replacement].

In 1091 patients with isolated Björk-Shiley, Lillehei-Kaster, Starr-Edwards, and St. Jude Medical mitral and aortic valve replacement, hemolysis parameters were determined (hemoglobin, LDH, haptoglobin, free plasma hemoglobin, reticulocyte count, serum bilirubin, transferrin, urine hemosiderin, schistocyte count). In 1006 of these patients no valve dysfunction was detected, while in 85 patients either paravalvular leakage or a thrombosis of the prosthetic valve was present. Haptoglobin was the most sensitive parameter for detecting even mild intravascular hemolysis, which was present in two-thirds of patients after alloprosthetic heart valve replacement. For quantifying red cell damage LDH was useful. Hemolysis was somewhat higher after Lillehei-Kaster and Starr-Edwards than after Björk-Shiley or St. Jude Medical implantation. The variance of LDH levels can be explained in a high percentage by correlating them with the hemodynamic findings at rest and exercise, which are indirect parameters of velocity profiles. Hemolysis is higher after aortic than after mitral valve replacement, with the exception of St. Jude valves. In patients with perivalvular leakage or valve thrombosis, red cell damage is more pronounced than in normally functioning prostheses (p less than 0.0005). When the hemolysis characteristics of the individual types of prosthesis are taken into account, the degree of hemolysis is a reliable indicator (p less than 0.05) of the functional integrity of the prosthesis. However, the degree of hemolysis does not correlate with the hemodynamic significance of perivalvular regurgitation.

Adolescent↗
PubMed1982

[Clinical follow-up of patients after valve replacement with Omniscience cardiac valves: can this valve be recommended? (author's transl)].

Clinical evaluation of 9 patients, after valve replacement with Omniscience cardiac valves (5 with aortic, 4 with mitral valve replacement) showed opening angles significantly lesser than the theoretical in-vitro valve of 80 degrees opening angles were essential by cineangiography. In 3 of 4 patients with mitral valve replacement, reoperation became necessary due to prosthetic valve dysfunction. Thus the implantation of Omniscience cardiac valves cannot be recommended.

Adult↗
PubMed2003

Progression of aortic valve stenosis: TGF-beta1 is present in calcified aortic valve cusps and promotes aortic valve interstitial cell calcification via apoptosis.

BACKGROUND: Aortic valve stenosis characteristically progresses due to cuspal calcification, often necessitating valve replacement surgery. The present study investigated the hypothesis that TGF-beta1, a cytokine that causes calcification of vascular smooth muscle cells in culture, initiates apoptosis of valvular interstitial cells as a mechanistic event in cuspal calcification. METHODS: Noncalcified and calcified human aortic valve cusps were obtained at autopsy or at the time of cardiac surgery. The distributions within cusps of TGF-beta1, latent-TGF-beta1-associated peptide, and TGF-beta receptors were studied using immunohistochemistry. The effects of TGF-beta1 on mechanistic events contributing to aortic valve calcification were also investigated using sheep aortic valve interstitial cell (SAVIC) cultures. RESULTS: Immunohistochemistry studies revealed that calcific aortic stenosis cusps characteristically contained within the extracellular matrix qualitatively higher levels of TGF-beta1 than noncalcified cusps. Noncalcified normal valves demonstrated only focal intracellular TGF-beta1. Addition of TGF-beta1 to SAVIC cultures led to a cascade of events, including: cellular migration, aggregation, formation of apoptotic-alkaline phosphatase enriched nodules, and calcification of these nodules. The time course of these events in the SAVIC culture system was rapid with nodule formation with apoptosis by 72 hours, and calcification after 7 days. Furthermore, ZVAD-FMK, an antiapoptosis agent (caspase inhibitor), significantly inhibited calcification and apoptosis induced by TGF-beta1, but had no effect on nodule formation. However, cytochalasin D, an actin-depolymerizing agent, inhibited nodule formation, but not calcification. CONCLUSIONS: TGF-beta1 is characteristically present within calcific aortic stenosis cusps, and mediates the calcification of aortic valve interstitial cells in culture through mechanisms involving apoptosis.

Aged↗