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PubMed2003

Tissue-engineered heart valve on acellular aortic valve scaffold: in-vivo study.

The feasibility of constructing a tissue-engineered heart valve on an acellular porcine aortic valve leaflet was evaluated. A detergent and enzymatic extraction process was developed to remove the cellular components from porcine aortic valves. The acellular valve leaflets were seeded for 7 days in vitro with cells from canine arterial wall and endothelial cells. The constructs were implanted into the lumens of 6 canine abdominal aortas to assess the reconstruction of the valve leaflets. It was found that all cellular components had been removed from the porcine aortic valves. The valve leaflets were completely reconstructed at the end of the 10th week in vivo. Scanning electron microscopy showed that the valve leaflets were partially covered with endothelial cells. It was concluded that porcine aortic valves can be decellularized by the detergent and enzymatic extraction process and it is feasible to construct a tissue-engineered heart valve in vivo on an acellular valve scaffold.

Animals↗
PubMed2001

Strut fracture of Björk-Shiley convexo-concave valve in Japan--risk of small valve size--.

BACKGROUND: The Björk-Shiley convexo-concave (BSCC) prosthetic valve was introduced in 1979. Between 1979 and 1986, approximately 86,000 BSCC valves were implanted. By December 31, 1994, 564 complete strut fractures had been reported to the manufacture. We experienced a case of an outlet strut fracture and investigated the risk of BSCC prosthetic valve fractures in Japan. METHODS AND RESULTS: To investigate the risk factor of a strut fracture in Japan, we investigated published cases of strut fractures. Between 1979 and 1986, 2021 BSCC valves were implanted in Japan. By January 31, 2000, 11 complete strut fractures of 60-degree BSCC valves including our case had occurred. The patients were eight males and three females. The average age at valve replacement was 42.4+/-8.1 years, and nine of eleven (81.8%) were patients < 50 years-old. The average age of the patients when the BSCC valve fractured was 47.7+/-6.4 years, and eight of eleven (72.7%) were patients <= 50 years old. All patients were implanted in the mitral position. The sizes of the BSCC valve were 27 mm (n=5) (45.5%), 29 mm (n=3) (27.2%), and 31 mm (n=3) (27.2%). Four patients died and seven patients survived. CONCLUSIONS: Although only 11 BSCC valve struts fractured and statistical analysis could not be performed, our findings suggest that the high risk group for a strut fracture in Japan is young male patients with a mitral valve, >= 27 mm in size with BSCC models manufactured before March 1982. When following-up patients with BSCC models manufactured before March 1982, the possibility of a strut fracture in all BSCC valve sizes should be kept in mind.

Adult↗
PubMed2002

Decision-making in the choice of heart valve for replacement in patients aged 60-70 years: twenty-year follow up of the St. Jude Medical aortic valve prosthesis.

BACKGROUND AND AIM OF THE STUDY: The choice of a cardiac valve for patients with aortic valvular pathology remains controversial. Younger patients may be at risk for long-term complications from chronic anticoagulation yet require prosthesis longevity, while older patients may not outlive a bioprosthesis. To gather information to help decision-making, the 20-year experience of aortic valve replacement (AVR) with the St. Jude Medical (SJM) valve by the surgeons of Cardiac Surgical Associates, P.A., was reviewed. METHODS: Cardiac Surgical Associates Research Foundation maintains a database of all patients undergoing valve replacement with the SJM aortic prosthesis since the world's first implant in October 1977. Patient follow up is conducted by questionnaire and/or telephone interview. The 20-year follow up period ended in October 1997. Follow up is 96.3% complete, and extends to 13,208 patient-years. RESULTS: A total of 2,390 aortic valves (1,500 in males, 890 in females) were replaced in the period studied. Among these patients, 1,419 had isolated AVR, whilst the remainder had AVR plus coronary artery bypass (CAB) or other procedures. The mean age was 63 +/- 14 years for AVR, and 70 +/- 10 years for AVR/CAB. Over the 20-year follow up period, freedom from valve-related events for the entire group was: thromboembolism, 97%; anticoagulant-related hemorrhage, 94%; valve thrombosis, 99.7%; prosthetic valve endocarditis, 99.2%; and paravalvular leak, 99.6%. Freedom from structural failure was 100%. Mortality for these events was low (15 deaths among 250 events; 6%). Overall survival at 5, 10, 15 and 19 years was 82, 66, 51 and 45% respectively for isolated AVR, and 72, 45, 25 and 15% respectively for AVR/CAB. CONCLUSION: The SJM valve has excellent hemodynamics and a low incidence of valve-related complications. Improvements in anticoagulation monitoring with the newly introduced and funded home monitoring program, as well as the introduction of newer and more effective antiplatelet drugs, will improve the safety of patients requiring chronic anticoagulation. With durability unquestioned, these long-term data show the SJM valve to be an excellent choice for AVR in patients aged 60-70 years.

Age Factors↗
PubMedDate not supplied

Aortic valve replacement with a stentless porcine bioprosthesis: multicentre trial. Canadian Investigators of the Toronto SPV Valve Trial.

OBJECTIVE: To evaluate the clinical and hemodynamic performance of a new bioprosthesis for replacement of the aortic valve in humans. STUDY DESIGN: In a multicentre clinical trial between July 1991 and January 1994, 118 patients underwent aortic valve replacement with the Toronto SPV valve. RESULTS: Valvular pathology was aortic stenosis in 58%, insufficiency in 12% and mixed valvular disease in 30%; congenital bicuspid aortic valve was seen in 42% while heavy calcification was present in 86%. In approximately a third of the patients, concomitant coronary artery bypass surgery was performed. The mean period of aortic occlusion was 89 mins (range 48 to 180). Valve sizes implanted were: 22 mm (1%), 23 mm (7.6%), 25 mm (22.9%), 27 mm (37.3%) or 29 mm (31.4%). There were three deaths in the series: two from subacute bacterial endocarditis and one suicide. Early complications were cardiac arrest (0.8%), thromboembolism (2.5%) and arrhythmia (12.7%), while late complications were cardiac arrest (0.8%), arrhythmia (4.7%), angina (0.8%), thromboembolism (4.4%), endocarditis (1.7%) and other sepsis (0.8%). There were no valve related failures in 119 valve-years (mean follow-up 1.01 valve-year per patient). Follow-up echocardiography demonstrated an average decrease in mean systolic gradient of 36% from early to late postoperative period (P < 0.001) and an average increase in effective orifice area of 35% (P < 0.001) in the same period. No regurgitation was noted in 91% of patients at early, and 89% of patients at late, follow-up. CONCLUSIONS: The Toronto SPV valve offers excellent hemodynamics, is relatively easy to insert and has few valve related complications. The observed changes in transvalvular area over time are consistent with a hypothesis that the ventricle undergoes remodelling following aortic valve replacement with this bioprosthesis. Longer follow-up is required to determine durability.

Animals↗
PubMed1979

Mitral valve commissurotomy versus replacement. Considerations based on examination of operatively excised stenotic mitral valves.

Among 164 patients who underwent mitral valve replacement because of mitral stenosis (with or without mitral regurgitation) and had radiographs taken of their operatively excised mitral valves, 20 had absent or minimal calcific deposits in the excised valves and absent or minimal mitral regurgitation as determined, except for one patient, by left ventricular angiography preoperatively. This report focuses on these 20 patients to ask if mitral valve replacement was preferable to mitral valve commissurotomy. Although in the pre-valve replacement era, all 20 patients almost surely would have been considered good candidates for mitral commissurotomy, other factors, namely, the need to replace one or more other cardiac valves (13 patients), the utilization of cardiopulmonary bypass allowing visual inspection rather than simple palpation of the diseased mitral valve (all 20 patients), relatively little experience with mitral commissurotomy in four of the five surgeons (17 patients), displeasure with attempted commissurotomy (three patients), previous mitral commissurotomy (11 patients), and incorrect identification of mitral calcific deposits (two patients), each contributed in one or more patients to the final decision of replacement versus commissurotomy. Even though mitral commissurotomy has been in use for 30 years, the mere alternative of valve replacement may have altered somewhat the definition of the stenotic mitral valve previously considered ideal for mitral commissurotomy.

Adult↗
PubMed2004

Long-term results of aortic valve replacement with the St. Jude Toronto stentless porcine valve.

BACKGROUND: Long-term survival and freedom from valve-related events of the St. Jude Toronto stentless porcine valve (SPV) are unknown. The aim of this study was to investigate late clinical outcomes after aortic valve replacement with the Toronto SPV. METHODS: Between 1992 and 2000, 200 patients (131 males, 69 females) underwent aortic valve replacement with the Toronto SPV. Mean patient age at implantation was 64.6 +/- 10.9 years (range 33 to 82 years). At the time of operation, 32%, 51%, and 17% of patients were in New York Heart Association class I/II, III, and IV, respectively. Aortic stenosis, aortic insufficiency, and combined lesions were present in 64%, 13.5%, and 22.5% of patients preoperatively. Concomitant coronary artery bypass grafting was performed in 34.5% of patients. RESULTS: Perioperative mortality occurred in 2.5% (5/200) of patients. There were 31 late deaths. Actuarial survival at 5 and 10 years was 89.2% and 68.0%, respectively. There was no significant difference in overall actuarial survival between isolated valve patients and valve plus coronary artery bypass grafting patients, 71% versus 62% respectively, p = 0.85. Actuarial freedom from valve reoperation at 5 and 10 years was 97.6% and 79.9%, respectively. Actuarial freedom from structural valve deterioration was 98.8% at 5 years and declined to 77.9% at 10 years. Freedom from structural valve deterioration was poorer in patients with preoperative aortic insufficiency or bicuspid disease. Actuarial freedom from embolic events and endocarditis at 10 years were 94.6% and 95.9%, respectively. CONCLUSIONS: Although early clinical results were excellent, a significant increase in hazard for structural valve deterioration occurred in late follow-up.

Actuarial Analysis↗
PubMed2001

Tricuspid valve surgery for functional tricuspid valve regurgitation associated with left-sided valvular disease.

OBJECTIVES: We have reviewed 260 patients who underwent initial tricuspid valve surgery for functional tricuspid valve regurgitation (TR) and analyzed independent predictors for early and late unfavorable results. MATERIALS AND METHODS: Between 1981 and 1998, 260 tricuspid valve operations were performed for functional TR. There were 94 males and 166 females with a mean age of 55 years. The tricuspid valve surgery procedures consisted of De Vega tricuspid annuloplasty in 240 patients, ring annuloplasty in four patients, and tricuspid valve replacement in 16 patients. The mean duration of follow-up was 7.8 years. RESULTS: Hospital mortality was 8.9% (23 patients). Late deaths occurred in 34 patients including cardiac-related late deaths in 26 patients. The survival rates were 83+/-2% at 5 years and 78+/-3% at 10 years. Late tricuspid valve reoperation was performed on 13 patients due to residual or recurrent TR in 12 patients and thrombosed tricuspid bileaflet mechanical valve in one patient. The tricuspid valve reoperation-free survival rate was 90+/-2% at 5 years and 84+/-3% at 10 years. The only predictor of hospital mortality was preoperative highly elevated right atrial pressure (P=0.01). Variables predictive of cardiac-related late death were preoperative New York Heart Association (NYHA) class IV (P=0.01) and poor left ventricular ejection fraction (LVEF) (P=0.02). Residual TR of more than grade 2+ early after tricuspid annuloplasty was a significant risk factor for late tricuspid valve reoperation (P=0.01). Preoperative TR of grade 4+ was predictive of early residual TR (P=0.04). CONCLUSIONS: Tricuspid valve surgery for functional TR can be performed with acceptable levels of early mortality. Cardiac-related late mortality after tricuspid surgery may be improved by earlier surgical treatment before NYHA class IV or deterioration of LVEF occurs. To prevent late tricuspid reoperation, it is important not to leave residual TR of grade 2+ or more after tricuspid annuloplasty.

Aged↗
PubMed1987

Tricuspid regurgitation in patients with acquired, chronic, pure mitral regurgitation. II. Nonoperative management, tricuspid valve annuloplasty, and tricuspid valve replacement.

The incidence, preoperative and intraoperative diagnosis, methods, and the clinical and hemodynamic features of patients with and without tricuspid regurgitation associated with chronic mitral regurgitation were presented in Part I. This study (Part II) compares the early and late results in patients with chronic, pure mitral regurgitation undergoing isolated mitral valve replacement, mitral replacement and tricuspid valve annuloplasty, and mitral and tricuspid valve replacement. The mean follow-up interval was 6 years. Those with the longest duration of symptoms (18 years) required tricuspid and mitral valve replacement (11 patients), whereas those with the shortest duration (8.1 years) had only mitral replacement (22 patients). Eight patients had minimal tricuspid regurgitation by digital palpitation, with no procedure performed, and six had tricuspid valve annuloplasty, only one of whom received a ring support. Operative mortality rate was similar in all groups (13% to 18%). All but two of the surviving patients improved by at least one New York Heart Association functional class, and no statistically significant differences were found between preoperative and postoperative hemodynamic data. There were no statistically significant differences in survival at 1, 5, or 8 years (85%, 70%, and 60%, respectively) for patients with or without TR. Only two of the surviving five patients who underwent tricuspid valve annuloplasty were alive 3 years after operation, whereas 70% to 80% of those with mitral replacement or mitral and tricuspid replacement were alive after the same time interval. It is not clear whether or not the pathogenesis of tricuspid regurgitation resulting from mitral regurgitation is different from that of tricuspid regurgitation resulting from mitral stenosis. It is our contention that whether tricuspid regurgitation arises because of anatomic destruction of the tricuspid valve or because of right ventricular dilatation with tricuspid annular enlargement, the underlying mitral valve lesion may determine the preoperative and postoperative courses of these patients. Therefore, when tricuspid valve disease is being evaluated, we urge that patients be categorized by the nature of their underlying mitral or aortic valve lesions.

Adult↗
PubMed2001

Surgically created double-orifice left atrioventricular valve: a valve-sparing repair in selected atrioventricular septal defects.

OBJECTIVES: Some features of the left atrioventricular valve (large mural leaflet, dystrophic tissue) represent a challenge for repair of atrioventricular septal defects without postoperative regurgitation. A retrospective study was conducted to evaluate the results of surgically creating a double-orifice left atrioventricular valve in such circumstances. Clinical results were analyzed according to valvular and subvalvular left atrioventricular valve measurements in pathologic specimens with atrioventricular septal defects. METHODS: Among 157 patients operated on for atrioventricular septal defect since October 1989, 10 patients underwent primary repair (n = 8) or reoperation (n = 2) by this procedure. Median age at repair was 3.3 years (0.1-33 years). Anatomic types were complete (n = 3), intermediate (n = 5), and partial (n = 2). Preoperative moderate to severe left atrioventricular valve regurgitation was present in 6 patients. After the repair (two-patch technique in complete atrioventricular septal defect, cleft closed in each case), these 10 patients were found to have moderate to severe residual regurgitation not amenable to repair by annuloplasty. The top edge of the mural leaflet was anchored to the facing free edge of the cleft. RESULTS: No hospital death or morbidity was observed. Left atrioventricular valve regurgitation was absent or trivial (8 patients) and mild (2 patients). Color-coded echocardiography did not show significant left atrioventricular valve stenosis. The mean diastolic pressure gradient across the left atrioventricular valve was 3.2 +/- 1.1 mm Hg (1.4-4.5 mm Hg). At a median follow-up of 72 months (6-91 months), there was 1 late death, unrelated to left atrioventricular valve malfunction, due to pulmonary vascular obstructive disease. Left atrioventricular valve regurgitation did not increase over time, except in 1 patient in whom regurgitation recently progressed from mild to moderate. At rest, the mean diastolic pressure gradient across the left atrioventricular valve was 3.8 +/- 2.9 mm Hg (1.5-11.2 mm Hg). One child had an early moderate stenosis without pulmonary hypertension. Studies on pathologic specimens (n = 34) indicated that long chordal lengths and large mural leaflet size are essential independent anatomic features to assess its feasibility. CONCLUSIONS: Surgical creation of a double-orifice left atrioventricular valve is an effective additional procedure for repair of atypical cases of atrioventricular septal defect. The operation may decrease the need for reoperation or left atrioventricular valve replacement.

Adult↗
PubMed1987

A new bioprosthesis for aortic and mitral valve replacement: preliminary evaluation of the Tascon valve.

The Tascon valve, a new porcine bioprosthesis, features a detachable sewing ring designed to facilitate insertion and removal. Between April 1984 and June 1986, we implanted the Tascon valve in 25 patients, 12 of whom underwent aortic valve replacement (AVR), and 13 of whom had mitral valve replacement (MVR). Most of the patients were in NYHA class III or IV. Four MVR patients had had previous mitral valve operations, and three AVR patients required composite graft valved conduits. The valve's screw-locking mechanism worked well in all cases, especially in the AVR cases. There were no hospital deaths, and no significant morbidity or valve-related complications were encountered. One late death occurred 3 months after surgery, owing to causes unrelated to the valve. At the end of the study period, most of the survivors had improved by at least two NYHA functional classes. Postoperative aortic and mitral valve gradients and mitral valve areas, as measured by Doppler methods, were excellent. No significant regurgitation was detected. These favorable results indicate that the Tascon valve is a safe, useful bioprosthesis, with satisfactory hemodynamic characteristics.

Journal Article↗
PubMed1997

Primary valve malfunction of the Krupin eye valve with disk.

PURPOSE: To examine the management and possible causes of primary valve malfunction of the Krupin eye valve with disk. METHODS: The authors reviewed the results of 113 patients undergoing implantation of the Krupin eye valve with disk and identified eight patients with primary valve malfunction requiring surgical revision. RESULTS: Valve revision involved manipulation (n = 1 case), explantation of the malfunctioning valve and implantation of a new valve (n = 2), and amputation of the valve (n = 5). Six of eight patients had final intraocular pressures of < 21 mmHg on one or no medications at a mean interval of 15.9 months (range 5-36) after surgical revision. Transient postoperative hypotony was noted in three patients and chronic hypotony with loss of light perception in one patient. One explanted valve was examined and found to have partially fused leaflets. CONCLUSIONS: Surgical revision in cases of primary valve malfunction of the Krupin eye valve with disk may be accomplished relatively safely with an acceptable level of postoperative complications. The etiology of primary valve malfunction may be related to the sterilization process and prolonged storage before implantation.

Filtering Surgery↗
PubMed1992

Single-plane transesophageal echocardiography for assessing function of mechanical or bioprosthetic valves in the aortic valve position.

To assess the value and limitations of single-plane transesophageal echocardiography in the evaluation of prosthetic aortic valve function, 89 patients (69 mechanical and 20 bioprosthetic aortic valves) were studied by combined transthoracic and transesophageal 2-dimensional and color flow Doppler echocardiography. In the assessment of aortic regurgitation, the transthoracic and transesophageal echocardiographic findings were concordant in 71 of 89 patients (80%). In 8 patients, the degree of aortic regurgitation was underestimated by the transthoracic approach; in each case the quality of the transthoracic echocardiogram was poor. In 10 patients, transesophageal echocardiography failed to detect trivial aortic regurgitation due to acoustic shadowing of the left ventricular outflow tract from a mechanical valve in the mitral valve position. Transesophageal echocardiography was superior to transthoracic echocardiography in diagnosing perivalvular abscess, subaortic perforation, valvular dehiscence, torn or thickened bioprosthetic aortic valve cusps, and in clearly distinguishing perivalvular from valvular aortic regurgitation. Transesophageal echocardiography correctly diagnosed bioprosthetic valve obstruction in 1 patient, but failed to diagnose mechanical valve obstruction in another. In conclusion, transesophageal echocardiography offers no advantage over the transthoracic approach in the detection and quantification of prosthetic aortic regurgitation unless the transthoracic image quality is poor. Transesophageal echocardiography is limited in detecting mechanical valve obstruction and in detecting aortic regurgitation in the presence of a mechanical prosthesis in the mitral valve position. However, it is superior to transthoracic echocardiography in identifying perivalvular pathology, differentiating perivalvular from valvular regurgitation and in defining the anatomic abnormality responsible for the prosthetic valve dysfunction. Combined transthoracic and transesophageal examination provides complete anatomic and hemodynamic assessment of prosthetic aortic valve function.

Adolescent↗
PubMed1995

Mitral valve replacement with a collar-reinforced prosthetic valve for disrupted mitral annulus.

The mitral valve was replaced with a collar-reinforced prosthetic valve in 6 patients with a disrupted mitral annulus, in 3 because of infective endocarditis, including 2 patients with prosthetic valve endocarditis, in 2 because of a severely calcified mitral annulus, and in 1 who had previously undergone mitral valve replacement twice. Four patients had undergone prior mitral operations; these consisted of mitral valve replacement in 3 patients and mitral valve repair in 1. In all patients, the prosthesis was secured by double-layered sutures, with the first row of buttressed sutures passing through the leaflet or sutured to the left ventricular muscle and through the sewing cuff of the prosthetic valve. The second row of running sutures was then placed through an extended annular equine pericardial cuff of the prosthetic valve and the supraannular left atrial wall. In 2 patients, all chordae tendineae were preserved to maintain annulopapillary muscle continuity. All patients survived and have remained well for a mean of 22.3 months. There has been no prosthetic valve dehiscence, except for minimal paraprosthetic leakage in 1 patient. These results demonstrate that mitral valve replacement in patients with a disrupted mitral annulus can be successfully accomplished with a collar-reinforced prosthetic valve.

Aged↗
PubMed2004

Use of the mitral valve-tricuspid valve distance as a marker of fetal endocardial cushion defects.

OBJECTIVE: The purpose of this study was to compare the mitral valve-tricuspid valve distance in second-trimester fetuses with normal cardiac anatomy versus those fetuses with endocardial cushion defects. STUDY DESIGN: We identified fetuses between 16 and 24 weeks of gestation. The distance between the insertions of the medial leaflets of the mitral and tricuspid valves were obtained. Linear regression curves were generated. RESULTS: The mean mitral valve-tricuspid valve distance for 86 fetuses with normal cardiac anatomy was 2.02 mm, compared with 0.37 mm in 13 fetuses with endocardial cushion defects ( P = .0001). Linear regression curve correlating mitral valve-tricuspid valve distance with gestational age showed a gradual slope (R 2 = 0.28; P < .0001). With a mitral valve-tricuspid valve distance < 5th percentile as a marker for the diagnosis of endocardial cushion defect gave a sensitivity of 69.2%, a specificity of 100%, a positive predictive value of 100%, a negative predictive value of 95.6%, and a false-positive rate of 0% ( P = .0001). CONCLUSION: The mitral valve-tricuspid valve distance is useful clinically in the detection of endocardial cushion defects in second-trimester fetuses.

Endocardial Cushion Defects↗
PubMed2002

Analysis of valve motion after the reimplantation type of valve-sparing procedure (David I) with a new aortic root conduit.

BACKGROUND: The reimplantation type of valve-sparing procedure does not allow proper reconstruction of the sinuses of Valsalva. We assessed the valve motion after a reimplantation type (David I) of valve-sparing procedure using a new Dacron conduit that incorporates sinuses of Valsalva. METHODS: Nine consecutive patients undergoing an aortic valve-sparing procedure using the new conduit were studied using two-dimensional transesophageal echocardiography shortly (2 +/- 1 months) after operation to determine root distensibility, expressed as percent change in radius and as pressure strain of the elastic modulus. Next, monodimensional view was used to assess valve motion in its various phases (rapid valve opening velocity, slow closing leaflet displacement, rapid valve closing velocity, maximal leaflet displacement, and leaflet displacement before valve closure). Seven healthy individuals served as control subjects. RESULTS: Root distensibility was reduced at the level of the annulus and sinotubular junction but was similar to control subjects at the level of the sinuses (percent change in radius, 4.1% +/- 0.8% versus 4.5% +/- 1.2%; pressure strain of the elastic modulus, 1,286 +/- 674 g/cm2 versus 1,195 +/- 628 g/cm2). Rapid valve opening (69 +/- 34.4 cm/s versus 51 +/- 11.9 cm/s) and closing (47.6 +/- 16 cm/s versus 36.4 +/- 9 cm/s) velocity as well as slow closing leaflet displacement (24% +/- 4.7% versus 22.1% +/- 7.9%), maximal leaflet displacement (20.1 +/- 4 mm versus 22.7 +/- 1.9 mm), and leaflet displacement before valve closure (15.2 +/- 3 mm versus 17.6 +/- 0.8 mm) were similar to control subjects. CONCLUSIONS: The new aortic root conduit used in a reimplantation type of valve-sparing procedure allows the anatomic reconstruction of the aortic root with leaflet motion similar to that of normal subjects.

Aged↗
PubMed2002

The importance of secondary mitral valve involvement in primary aortic valve endocarditis; the mitral kissing vegetation.

AIMS: Secondary involvement of the mitral valve is well documented in primary aortic valve endocarditis. A poorly considered, but probably important causative mechanism, involving both left-sided valves, is 'mitral kissing vegetation'. This results from large aortic vegetations prolapsing into the left ventricular outflow tract and making contact with the ventricular aspect of the anterior mitral leaflet thus causing secondary infection. METHODS AND RESULTS: In 192 consecutive patients with aortic valve endocarditis, two to 18 (7.6+/-2.6) serial transoesophageal echocardiographic examinations were analysed per patient to demonstrate the development of mitral kissing vegetation on initially competent, morphologically normal mitral leaflets. In 19 patients (9.9%) with aortic valve endocarditis, mitral kissing vegetation was diagnosed within 11.6+/-9.0 (range 1-31) days following primary transoesophageal echocardiography. In all patients with mitral kissing vegetation, vegetations attached to aortic cusps were >6 mm. On hospital admission, patients with aortic valve endocarditis plus mitral kissing vegetation presented more often with a positive sepsis score, embolic events, renal failure and had larger aortic valve vegetations (9.9+/-3.3 vs 5.7+/-2.3 mm). Prognosis of aortic valve endocarditis plus mitral kissing vegetation was unfavourable (P<0.005) when compared to patients with aortic valve endocarditis alone. CONCLUSION: In aortic valve endocarditis early echocardiographic detection of mitral kissing vegetation and timely surgery may preserve the mitral valve apparatus, and favourably influence the long-term prognosis.

Adolescent↗
PubMed1980

Chronic haemolysis after Lillehei-Kaster valve replacement. Comparison with the findings after Björk-shiley and Starr-Edwards mitral valve replacement.

Nineteen female and sixteen male patients who have had their heart valves replaced with Lillehei-Kaster valves were investigated for haemolysis four to 18 months after operation. Investigation included serum lactic dehydrogenase, serum haptoglobins, and urine haemosiderin. Red cells survival, using autologous red cells labelled with 51Cr, was measured in 12 patients. No patient showed manifest anaemia. The serum lactic dehydrogenase levels were raised in 66% of the mitral valve patients, 81% of the aortic valve patients, and in all the double valve patients. The serum haptoglobins were decreased in 66% of mitral patients, 68% of aortic valve patients, and in 75% of the double valve patients. All the 12 patients studied had lower than normal red cell survivals. No correlation was found between the incidence of haemolysis and the size of the valve. In isolated mitral valve replacement 66% showed compensated haemolysis compared with 42% in Björk-Shiley valves (p less than 0.05), 85% in Starr-Edwards valves (composite seat) (p less than 0.01), and none in frame-mounted irradiated homografts (previous study) (p less than 0.001).

Female↗
PubMed1999

The SynerGraft valve: a new acellular (nonglutaraldehyde-fixed) tissue heart valve for autologous recellularization first experimental studies before clinical implantation.

The durability of current bioprosthetic heart valves is diminished by glutaraldehyde-associated leaflet calcification or by the associated absence of a cellular component capable of repair of wear-related damage. As a novel tissue engineering approach to improving replacement heart valve durability, we have developed a decellularization process to replace the use of cross-linking to limit xenograft antigenicity. The effectiveness of this process was assessed in a weanling sheep right ventricular outflow tract reconstruction model where valve function, calcification, and recellularization were examined. Porcine aortic valves were decellularized by a process designed to remove all histologically demonstrable leaflet cells. Stentless, bioprosthetic valves were fabricated from acellular tissues, cryopreserved, sterilized, and then implanted as pulmonary valve replacements in 4- to 6-month old female Suffolk sheep. Sheep aortic valves were implanted as allograft control subjects. After 150 days, the grafts were explanted and assessed histologically and by atomic absorption spectrophotometry for calcium content. All valves were hemodynamically functional at explant. Histological examination showed intact leaflets with in-growth of host fibroblastoid cells in all explanted porcine valves and no evidence of calcification. Porcine leaflet calcium content was unchanged over the duration of the implant (1.0+/-1.2 vs 1.5+/-1.8 mg/g dry weight, P = ns). Decellularization can stabilize xenogenic heart valves. Lack of calcification of acellular aortic leaflets suggests that prolonged durability of such valves is attainable without the use of cross-linking agents. The repopulation of the leaflet matrix offers additional promise of durability based on revitalization of the graft in vivo.

Animals↗