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PubMed1997

Donor-specific anti-human leukocyte antigen class I antibodies after implantation of cardiac valve allografts.

The allospecific humoral immune response was examined in 31 patients in the first year after implantation of cryopreserved human cardiac valves. We determined the percentage antibodies against human leucocyte antigens (HLA) class I in a complement-dependent microlymphocytotoxicity test against a panel of 50 selected donors carrying most of the defined HLA-A and HLA-B specificities (panel-reactive antibodies). In blood samples taken immediately before implantation, no antibodies could be detected. Thereafter, antibodies were present in 23 of 31 (74%) patients (median panel-reactive antibodies: 57%, range 9% to 91%). In 21 patients the HLA-type of the valve donor was available. In four patients no blood samples taken after 4 weeks were available. In 14 of 17 patients (82%) with a follow-up of more than 1 month antibodies were present, and in 12 of these 14 (86%) antibodies were specifically directed against HLA class I of the donor. In conclusion, the formation of donor-specific antibodies is frequently observed after human cardiac valve replacement. It could be one of the factors leading to valve destruction and dysfunction.

Adolescent↗
PubMed1978

Discontinuing anticoagulant therapy in surgical patients with cardiac valve prostheses. Observations in 180 operations.

Between 1962 and 1975, a total of 159 patients with previously implanted man-made cardiac valve prostheses underwent 180 subsequent noncardiac operations at Mayo Clinic. All of these patients were receiving anticoagulants. The overall incidence of their documentable thromboembolic complications was approximately 10%. None of the postoperative complications occurred while the patient was in hospital, with the earliest such complication seen two years later. Patients receiving anticoagulants on a long-term basis did, however, have a 13% incidence of various difficulties with hemostasis during and following the later operations. We conclude that there is minimal risk to patients with cardiac valve prostheses who are receiving anticoagulants when the drug regimen is stopped for one to three days preoperatively and one to seven days postoperatively.

Adolescent↗
PubMed2001

Association of inflammation and malnutrition with cardiac valve calcification in continuous ambulatory peritoneal dialysis patients.

Cardiac valve calcification (VC) has long been regarded as a consequence of aging and abnormal calcium-phosphate metabolism in uremic patients. In view of the recent recognition of association among inflammation, malnutrition, and atherosclerosis, the possible role of inflammation and malnutrition in VC was investigated. Inflammatory markers (including C-reactive protein [CRP], fibrinogen, and basal metabolic rate) and nutritional status (assessed using serum albumin, subjective global nutrition assessment, and handgrip strength) were examined, in addition to calcium phosphate parameters and other traditional cardiovascular risk factors, including gender, smoking habits, BP, and lipid profile, in relation to VC in 137 patients who were on continuous ambulatory peritoneal dialysis. Compared with patients with no VC, patients with VC not only were older (60 [10] versus 54 [12] yr; P = 0.005), had higher plasma phosphate (1.89 [0.52] versus 1.64 [0.41] mmol/L; P = 0.003), and had higher parathyroid hormone (83 [40, 145] versus 38 [16, 71] pmol/L; P = 0.001) but also had higher CRP (4.5 [0.1, 13.4] versus 0.2 [0.1, 4.4] mg/L; P = 0.004), had higher fibrinogen (6.6 [1.9] versus 5.7 [1.3] g/L; P = 0.002), and had lower serum albumin (26 [4] versus 29 [3] g/L; P = 0004). Twenty-three percent of patients with VC versus 17% of patients with no VC were moderately to severely malnourished according to subjective global nutrition assessment (P = 0.05). Even after adjustment for patients' age, duration of continuous ambulatory peritoneal dialysis, diabetes, and calcium x phosphate product, cardiac VC remained strongly associated with CRP (odds ratio, 1.05; P = 0.026) and albumin (odds ratio, 0.85; P = 0.01). The data suggest that VC not only is a passive degenerative process but also involves active inflammation, similar to that seen in atherosclerosis. The presence of uncontrolled hyperphosphatemia and hyperparathyroidism further accelerates the progression of calcification. The data also indicate that VC and atherosclerosis should be considered as associated syndromes, sharing similar pathogenic mechanisms, namely active inflammation.

Adult↗
PubMed1999

Effects of coenzyme Q10 on myocardial protection during cardiac valve replacement and scavenging free radical activity in vitro.

BACKGROUND: To evaluate the effects of CoQ10 on myocardial protection in patients undergoing cardiac valve replacement and direct scavenging free radicals activity in vitro. METHODS: Twenty-four patients were randomly divided into two groups. Twelve patients in the CoQ10 group received intravenous and intracoronary CoQ10-treated "round the operative period". Twelve patients in the control group received no CoQ10-treatment. MEASURES: Plasma malondialdehyde (MDA) concentration, erythrocyte superoxide dismutase (SOD) activity, and serum cardiac isoenzyme of creatine kinase (CK-MB) were measured in the perioperative and postoperative period. The effects of CoQ10 direct scavenging free radicals were determined with electron spin resonance (ESR) and spin-trapping techniques by an in vitro study. RESULTS: Plasma MDA concentration and serum CK-MB levels in the CoQ10 group were significantly lower than those in the control group. Erythrocyte SOD activity in the CoQ10 group was significantly higher than that in the control group. CoQ10 showed an obvious hydroxyl radical scavenging activity, but it could not scavenge superoxide anion radicals. CONCLUSIONS: These findings demonstrated that the use of intravenous and intracoronary CoQ10-treatment may play a more beneficial protective role during cardiac valve replacement through its antioxidant properties and membrane stabilization, as well as through its ability to scavenge hydroxyl radicals directly.

Adult↗
PubMed1992

[A 12-year clinical experience of cardiac valve replacement with domestic tilting disc valve prostheses in 1013 cases].

1013 patients with cardiac valve replacement during a 12-year period from 1978 to 1990 were reported. 566 cases were implanted with Shanghai-made tilting disc valve prostheses and 447 with Lanzhou-made (C-L valves). Mitral valve replacement (MVR) in 753 patients, aortic valve replacement (AVR) in 102 and double valves replacement (DVR) in 158. The overall early mortality rate was 6.2% with 4.9%, 7.8% and 11.3% after MVR, AVR and DVR respectively. Follow-up study was made in 3097.43 patient-year (mean 3.26 years). The late death rate was 1.6% patient-years and with 1.4, 1.8 and 3.2 after MVR, AVR and DVR respectively. The incidence of late valve-related complication (% patient-years) were: thromboembolism 0.39, anticoagulant-related hemorrhages 0.77, prostheses failure 0.22, prosthetic valve endocarditis 0.38, periprosthetic leak 0.12, and reoperations 0.38. The domestic tilting disc valve prostheses are considered to be qualified valves with low mortality and satisfactory results.

Adolescent↗
PubMed1990

Echocardiographic evaluation of prosthetic cardiac valves.

Comprehensive echocardiographic examination of patients with prosthetic cardiac valves using M-mode, two-dimensional, conventional, and color Doppler echocardiography represents an invaluable clinical tool in the serial follow-up of these patients. A thorough knowledge of these techniques and their limitations allows accurate assessment and prevention of misdiagnoses.

Echocardiography↗
PubMed1986

Late results after left-sided cardiac valve replacement in children.

Selection of types of cardiac valve substitutes for children remains controversial. Between 1976 and 1984, 166 children, 15 years of age or younger, underwent aortic (N = 53) or mitral valve replacement (N = 90) or both (N = 23). Biological prostheses were used in 84 patients and mechanical prostheses in 71; both a mitral bioprosthesis and an aortic mechanical valve were used in 11 patients. The overall early mortality was 9%. Mean follow-up intervals were 4.1 years for the bioprosthesis group, 3.3 years for the mechanical valve group, and 3.5 years for the group receiving both. The 7 year survival rates (+/- standard error) were 63% +/- 6% in the bioprosthesis group and 70% +/- 7% in the mechanical valve group (p = NS). After aortic valve replacement the 7 year survival rates were 66% +/- 14% (bioprosthesis group) and 77% +/- 9% (mechanical valve group) (p = NS); after mitral valve replacement the rates were 65% +/- 7% (bioprosthesis group) and 54% +/- 17% (mechanical valve group) (p = NS). The incidence of thromboembolic events was 0.6% +/- 0.4% per patient-year in the bioprosthesis group (none after aortic valve replacement, 0.8% +/- 0.6% per patient-year after mitral valve replacement) and 1.4% +/- 0.8% per patient-year in the mechanical valve group (0.7% +/- 0.7% per patient-year after aortic valve replacement, 4.0% +/- 2.8% per patient-year after mitral valve replacement) (p = NS). The linearized rates of reoperation were 10.4% +/- 1.8% per patient-year (bioprosthesis group) and 2.3% +/- 1.0% per patient-year (mechanical valve group) (p less than 0.001). The 7 year probability rates of freedom from all valve-related complications were 43% +/- 6% in the bioprosthesis group and 86% +/- 4% in the mechanical valve group (p less than 0.001). In the aortic position, a mechanical adult-sized prosthesis can always be implanted, and satisfactory long-term results can be anticipated. In the systemic atrioventricular position, the results are less than satisfactory with either type of prosthesis; every effort should be made to preserve the natural valve of the child.

Adolescent↗
PubMed1985

A 5 1/2 year experience with the St. Jude Medical cardiac valve prosthesis. Early and late results of 737 valve replacements in 671 patients.

Between June 12, 1978, and June 12, 1983, 737 St. Jude Medical valves were implanted in 671 patients (431 males, 240 females) ranging in age from 9 months to 82 years (mean 55 years); 16 of these patients (2.3%) were less than or equal to 15 years and 82 (12.2%) were greater than or equal to 70 years. Associated procedures were performed in 28.2% of the 500 aortic valve replacements, 13.3% of the 105 mitral valve replacements, and 10.6% of the 66 double mitral and aortic valve replacements. Hospital mortality (less than or equal to 30 days) was 3.6% (18/500 patients) for aortic, 4.7% (5/105 patients) for mitral, and 0% for double valve replacement. Only one of these 23 hospital deaths was possibly valve-related. Complete follow-up was achieved during December, 1983, and January, 1984, to provide a minimum follow-up of 6 months. Follow-up has been 100% for a total of 1,619 patient-years, with a mean follow-up of 2 1/2 years. There were 41 late deaths (6.1%): 30 in the aortic group, eight in the mitral group, and three in the double valve replacement group. Fourteen (34.2%) of these late deaths have been considered valve-related. At 5 1/2 years, the actuarial survival rate, hospital mortality excluded, is 91% for aortic, 90% for mitral, and 95% for double valve replacement. Functional improvement of these patients is quite satisfactory: Preoperatively, 60.3% were in Class III or IV of the New York Heart Association, whereas postoperatively, 99.5% of the patients are in Class I or II. As 78 patients (65 aortic, 10 mitral, and three double valve replacement) did not receive anticoagulation therapy for a total period of 84 patient-years, the incidence of valve thrombosis, systemic embolism, and sudden or suspicious deaths in this group was compared with that in a group of 630 patients (including 60 patients from the first group who were given anticoagulants afterwards) subjected to long-term anticoagulation for a total period of 1,535 patient-years. A significantly higher incidence of valve thrombosis and systemic embolism was observed in the absence of anticoagulation. Anticoagulant-related complications occurred in 10 patients, with an incidence of 0.65/100 patient-years. On the basis of this 5 1/2 years of experience, the St. Jude Medical valve appears to be an excellent mechanical prosthesis for cardiac valve replacement, in terms of hemodynamic performance and low thrombogenicity, in patients receiving anticoagulants.

Adolescent↗
PubMed2001

The initial United States experience with the ATS mechanical cardiac valve prosthesis.

From January 1, 1997 through June 30, 2000, 224 patients underwent valve replacement with the ATS Medical cardiac valve prosthesis under a USFDA-approved investigational device exemption study. Aortic valve replacement (AVR) was conducted in 152 patients (39 with coronary bypass) and mitral replacement (MVR) in 72 patients (18 with coronary bypass). Overall operative mortality was 1.8% (AVR = 2.8%, MVR = 0%), with only one valve-related death. In 372 patient-years of follow-up, there were an additional four patient deaths, two of which were valve related following a stroke. Valve-related complications included: thromboembolism (linearized rate = 3.8% per patient year), of which 3/11 had chronic deficits (0.8% per patient year); thrombosis (1 MVR = 0.8% per patient year); paravalvular leak (1 AVR = 0.4% per patient year); anticoagulant-related hemorrhage (1 AVR and 5 MVR = 1.6% per patient year) with no patient mortality; prosthetic valve endocarditis (1 MVR = 0.8% per patient year); and valve dysfunction (0%). Echocardiographic gradients were proportional to valve size and did not significantly change over the follow-up period. This study documented the ATS Medical prosthesis to be a valuable addition to the surgeon's armamentarium in the treatment of cardiac valvular disease.

Adult↗
PubMed2005

Cardiac valve calcifications and left ventricular hypertrophy in hemodialysis patients.

Cardiac valve calcification (VC) is a common finding in end-stage renal disease patients. It was shown recently that VC is an independent predictor for all-cause and cardiovascular mortality in peritoneal dialysis patients. In hemodialysis (HD) patients, VC was associated with all-cause and cardiovascular mortality, but after adjusting for other cardiovascular risk factors and complications, as well as left ventricular mass index (LVMI), it lost significance. The aim of the study was to assess the relationship between VC and left ventricular hypertrophy in hemodialysis patients. Echocardiographic examination with mitral and aortic valves assessment and LVMI calculation was performed in 65 HD patients ages 49+/-12, with duration of HD therapy 38+/-32 months. VC were found in 32 of 65 patients (49%)-Group VC(+), mitral valve calcifications (MVC) in 10, aortic valve calcifications (AVC) in 9, and both valves calcifications (MVC+AVC) in 13 patients. Patients with VC were older, on HD therapy were longer, had higher systolic and pulse pressure, and had higher LVMI. Patients with both VCs had the highest LVMI. No significant differences were found with respect to Ca, P, PTH, and mean Ca x P product, but the incidence of Ca x P product above 4.43 mmol2/L2 was higher in VC(+) compared with those without VCs. VC coexists with left ventricular hypertrophy, particularly when both valves are calcified. Even short-lasting incidents of increased Ca x P product may lead to cardiac VC.

Adult↗
PubMed1979

Platelet suppressant therapy in patients with prosthetic cardiac valves. Relationship of clinical effectiveness to alteration of platelet survival time.

Platelet survival time (SURV) has correlated with thromboembolism in patients with prosthetic cardiac valves. Sulfinpyrazone increases SURV. SURV (autologous labeling with 51Chromium) was measured in 126 patients who had aortic or mitral valve replacement. These patients were followed prospectively. Ninety-four with shortened SURV received sulfinpyrazone; 32 with normal SURV were not treated with platelet suppressants. Eighty-seven patients were anticoagulated with warfarin--67 with shortened SURV and 20 with normal SURV. Eleven patients have had thromboembolism, and all had shortened SURV (2.4 +/- 0.08 days; average half-time +/- SEM; normal 3.7 +/- 0.03 days; n = 26) none had an increase of SURV with sulfinpyrazone (2.3 +/- 0.09 days). Of 83 patients with shortened SURV who did not have embolism, sulfinpyrazone increased SURV in 59 (71%) 2.6 +/- 0.05 to 2.9 +/- 0.06 days). Of 35 patients with shortened SURV who failed to increase SURV with sulfinpyrazone, 11 (31%) had embolism; none of 59 (0%) with an increase of SURV with sulfinpyrazone had thromboembolism. These results suggest that patients with thromboembolism after prosthetic cardiac valve replacement have shortened SURV and that patients treated with slufinpyrazone who have thromboembolism do not have an increased SURV.

Aortic Valve↗
PubMedDate not supplied

Double cardiac valve replacement: a community hospital experience.

The morbidity and mortality of double cardiac valve replacement were assessed in a community hospital setting. Four hundred twenty-two cardiac patients undergoing valve replacement from 1977 to 1991 were analyzed. Forty-two patients underwent double valve replacement. The clinical variables associated with increased operative mortality (early and late) were determined. The overall operative mortality rate for valve replacement was 7.87% (29 of 422 patients). The mortality rate was 9.09% (3/33 patients) for double valve replacement and 11.11% (1/9 patients) for double valve replacement in conjunction with coronary bypass. The clinical variables associated with increased mortality were: significant reduction in preoperative left ventricular ejection fraction (< 35%); advanced age (> 60); presence of ischemic mitral valve disease; and preoperative functional class (New York Heart Association Functional Class IV). The results of this study suggest that strategies to diminish operative mortality should include assessment of risk preoperatively as well as anticipation of high mortality in selected subgroups.

Adult↗
PubMed2002

Thrombolytic therapy with tissue plasminogen activator for the treatment of nonstructural malfunction of bileaflet cardiac valve prostheses.

This study was conducted to determine the effect of thrombolytic therapy with tissue plasminogen activator (t-PA) for nonstructural malfunction of bileaflet cardiac valve prostheses. Twenty-seven patients with bileaflet prosthetic valve malfunction diagnosed by a combination of cineradiography and transthoracic echocardiography were treated with the administration of intravenous t-PA. The treatment resulted in complete success in 55.6% (15 of 27), partial success in 22.2% (6 of 27), and no change in 22.2% (6 of 27). In the complete success and partial success groups, the condition of the patients in 85.7% (18 of 21) of the cases improved within 24 h after the administration of t-PA. Six cases in whom thrombolytic therapy was instituted more than 1 month (ranged from 1 to 38 months, mean 14.7 months) after the diagnosis of prosthetic valve malfunction showed significantly less effectiveness of thrombolytic therapy with t-PA. Only one patient (3.7%) had a major complication (thromboembolism) after t-PA treatment. The results suggest that thrombolytic therapy with t-PA in patients with nonstructural malfunction of bileaflet cardiac valve prostheses is effective with low incidence of complication when the treatment is instituted early after the diagnosis.

Adult↗
PubMed1993

[Pregnancy after cardiac valve replacement: analysis of 21 cases].

A retrospective analysis of 21 cases with 23 pregnancies after cardiac valve replacement from August 1979 to March 1992. In 11 cases mechanical and in 10 biological valves were used, and in 18 cases with mitral valve replacement was done (MVR), in 1 case aortic valve replacement (AVR) and in 2 cases, both MVR and AVR were carried out 22 pregnancies in 20 cases with cardiac function grading I and II (New York Heart Association, NYHA) before pregnancy resulted in normal term deliveries and 1 case with grading III prior to pregnancy died of heart failure in the third trimester. All the cases treated with mechanical valve replacement received warfarin derivatives throughout pregnancy, and no malformation was found in their neonates. Issues related to pregnancy after cardiac valve replacement were discussed.

Adult↗
PubMed1988

Development of antithrombin antibodies following surgery in patients with prosthetic cardiac valves.

Although antibody inhibitors directed against blood coagulation factors are well known, antibody inhibitors directed against thrombin are rare. We describe three postsurgical patients with prosthetic cardiac valves who developed serum autoantibodies reactive with human and bovine thrombin, as demonstrated by coagulation studies and immunoblotting. Despite marked prolongation of the thrombin time in these patients, the inhibitors were not associated with significant clinical bleeding. The mechanism of antithrombin autoantibody formation following surgery in patients with prosthetic cardiac valves remains to be determined.

Adult↗
PubMed2004

Noninvasive assessment of influence of resistant respiration on blood flow velocities across the cardiac valves in humans--a quantification study by echocardiography.

UNLABELLED: The aim of our study is to quantitatively investigate influence of the intrathoracic pressure change on the four cardiac valves' velocities and further verify a new proposal of the mechanism of respiratory influence on hemodynamics. METHODS: Thirty healthy volunteers with no cardiopulmonary diseases were included. The intrathoracic pressure changes were measured with self-designed device. The velocity across the four cardiac valves during spontaneous respiration and with the intrathoracic pressure change at -4, -8, and -12 mmHg, respectively, were recorded simultaneously with the electrocardiogram and respiratory curve. The respiratory variation indices (RVIs) were calculated. The average RVIs of mitral, aortic, tricuspid, and pulmonary valves were 12.54%, 13.19%; 6.23%, 8.27%; 20.27%, 24.36%; and 6.45%, 7.69% with intrathoracic pressure change at -8 mmHg and -12 mmHg, respectively. All the above parameters have a significant difference from those during spontaneous respiration (P < 0.01 or P < 0.001). We concluded that it might be the respiratory intrathoracic pressure change that causes the change of the velocity across the valves.

Adult↗
PubMed2001

Bone formation and inflammation in cardiac valves.

BACKGROUND: For nearly a century, the mechanical failure of calcified heart valves was attributed to a passive degenerative process. Recently, several case reports described bone formation in surgically excised heart valves and suggested an unexpected process of tissue repair. METHODS AND RESULTS: We studied the prevalence and pathology of heterotopic ossification in 347 surgically excised heart valves (256 aortic, 91 mitral) in 324 consecutive patients (182 men, 142 women; mean age 68 years) who underwent cardiac valve replacement surgery between 1994 and 1998. The valves were examined microscopically to determine the prevalence and features of bone formation and remodeling. Two hundred eighty-eight valves (83%) had dystrophic calcification. Mature lamellar bone with hematopoietic elements and active bone remodeling were present in 36 valves (13%) with dystrophic calcification. Endochondral bone formation, similar to that seen in normal fracture repair, was identified in 4 valves. Microfractures were present in 92% of all valves with ossification. Neoangiogenesis was found in all valves with ossification. Bone morphogenetic proteins 2 and 4 (BMP 2/4), potent osteogenic morphogens, were expressed by myofibroblasts and preosteoblasts in areas adjacent to B- and T-lymphocyte infiltration in valves where ossification was identified. Mast cells were present in calcified and ossified valves and were especially prominent in atheromatous regions. CONCLUSIONS: Heterotopic ossification consisting of mature lamellar bone formation and active bone remodeling is a relatively common and unexpected finding in end-stage valvular heart disease and may be associated with repair of pathological microfractures in calcified cardiac valves.

Adult↗