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PubMed2006

The On-X heart valve: mid-term results in a poorly anticoagulated population.

BACKGROUND AND AIM OF THE STUDY: The study aim was to evaluate the clinical performance of the On-X heart valve in a socioeconomically disadvantaged population. Most patients were from an indigenous, poorly educated and geographically dispersed segment of the population where anticoagulation therapy was generally erratic. METHODS: Between 1999 and 2004, a total of 530 valves (242 mitral valves, 104 aortic valves, 92 double valves) was implanted in 438 patients (average age 33 years; range: 3-78 years). The most common reason for surgery was rheumatic valve disease (57%), followed by degenerative valve disease (11%) and infective endocarditis (9%). Follow up was 95% complete for a total of 746 patient-years (pt-yr). Among the patient population, 40% were either not anticoagulated or were unsatisfactorily anticoagulated. RESULTS: Hospital mortality was 2.3%, and none of the hospital deaths was valve-related. Mean (+/- SE) actuarial survival (including hospital deaths) at four years was: AVR 73.8 +/- 8.1%, MVR 83.4 +/- 5.7% and DVR 60.9 +/- 10.3%. Linearized rates (for AVR, MVR and DVR, respectively) for late complications (%/ pt-yr) were: bleeding events 0.6, 1.0, and 2.3; thrombosis 0.0, 0.2, and 0.0; endocarditis 0.6, 1.0, and 2.3; paravalvular leak 0.6, 0.2, and 0.0; systemic embolism 1.1, 1.5, and 3.5. Most systemic emboli were related to infective endocarditis. Among patients there were seven uncomplicated, full-term pregnancies. CONCLUSION: Bearing in mind the erratic anticoagulation coverage and high incidence of infective endocarditis, the results of this study may be regarded as encouraging. The low incidence of valve thrombosis (one case) was noteworthy. These data also suggest that the On-X valve may be implanted with relative safety in women wishing to have children.

Adolescent↗

PubMed2001

Evaluation of valve-related complications in patients with Sorin Bicarbon prosthesis: a seven-year experience.

BACKGROUND AND AIM OF THE STUDY: The study aim was to evaluate the medium-term results of aortic valve replacement (AVR), mitral valve replacement (MVR) and double valve replacement (DVR) with the Sorin Bicarbon prosthesis. METHODS: A total of 990 patients (568 men, 422 women; mean age 60+/-10 years; range: 20-86 years) was reviewed who received 1,108 Sorin Bicarbon prostheses between 1992 and 1998 at three institutions. AVR was performed in 541 patients (55%), MVR in 330 (33%) and DVR in 119 (12%). Concomitant procedures, mainly coronary artery grafting, were performed in 222 patients (22%). Follow up was 98% complete; total cumulative follow up was 3,091 patient-years. RESULTS: Hospital mortality was 3.7% (n = 37). There were 49 late deaths; actuarial survival at seven years was 88+/-2% after AVR, 86+/-5% after MVR, and 78+/-8% after DVR. At last follow up, 915 survivors were in NYHA functional class I or II. At seven years, actuarial freedom from valve-related deaths, valve thrombosis, embolism and bleeding respectively was 96+/-1%, 99+/-1%, 93+/-2% and 91+/-3% after AVR; 97+/-2%, 97+/-3%, 90+/-3% and 86+/-7% after MVR; and 92+/-6%, 98+/-1%, 64+/-2% and 82+/-2% after DVR. Reoperation was required in 20 patients (due to valve thrombosis in six, endocarditis in five and periprosthetic leak in nine). At seven years, actuarial freedom from reoperation was 97+/-1%, 96+/-2% and 84+/-9% after AVR, MVR and DVR, respectively; actuarial freedom from endocarditis was 99+/-1%, 99+/-1% and 95+/-5%. Nine patients experienced a nonstructural valve dysfunction (all periprosthetic leak), while no cases of structural failure were observed. CONCLUSION: The Sorin Bicarbon prosthesis has shown good medium-term results with regard to clinical improvement, and low incidence of valve-related complications. Thus, it appears to be a reliable valve substitute when the use of a mechanical prosthesis is indicated.

Actuarial Analysis↗

PubMed2006

Results of concomitant aortic valve replacement and coronary artery bypass grafting in the VA population.

BACKGROUND AND AIM OF THE STUDY: Concomitant aortic valve replacement (AVR) and coronary artery bypass grafting (CABG) is an established risk factor for diminished postoperative survival. Results from a VA population were reviewed in order to determine factors influencing early and late survival. METHODS: Between 1993 and 2003, a total of 401 patients underwent AVR at the authors' institution. Of these patients, 249 (62%; mean age 70.6 years) had combined AVR and CABG. Surgical indications were primarily aortic valve pathology (group A: n = 168; 68%), primarily coronary artery disease (CAD) (group B: n = 55; 22%), and both severe aortic and coronary disease (group C: n = 26; 10%). In total, 177 patients (71%) received a bioprosthesis, and 72 (29%) received a mechanical valve. Short- and long-term outcomes were explored using univariate and multivariable hazard analyses. RESULTS: Overall operative mortality was 6.4%; mortality for groups A, B and C was 4.8%, 9.1% and 11.5%, respectively. On multivariable analysis, significant factors associated with early-phase mortality were NYHA class IV, diabetes, bioprosthetic valve and combined severe aortic and coronary disease. Survival at one and five years was 86% and 62%, respectively. Five-year survival for groups A, B and C was 71%, 63% and 54%, respectively. Significant associated factors for late-phase mortality were the presence of preoperative peripheral vascular disease (PVD) and cerebrovascular disease (CVD). Factors such as age, prior cardiac surgery, number of grafted coronary arteries, and/or effective orifice area index (EOAI) had no significant effect on outcome. CONCLUSION: Combined AVR/CABG is a marker for decreased survival. Pre-existing factors such as diabetes, PVD and CVD, as well as poor preoperative NYHA functional status, affected survival. Further investigation is needed to assess the influence of the severity of CAD and EOAI on survival. Thoughtful consideration of all these factors is essential for an accurate prediction of survival, and to determine the appropriate type of aortic prosthesis to be used.

Age Factors↗

PubMed2000

Aortic valve replacement: is valve size important?

OBJECTIVE: We sought to determine whether aortic prosthesis size adversely influences survival after aortic valve replacement. METHODS: A total of 892 adults receiving a mechanical (n = 346), pericardial (n = 463), or allograft (n = 83) valve for aortic stenosis were observed for up to 20 years (mean, 5.0 +/- 3.9 years) after primary isolated aortic valve replacement. We used multivariable propensity scores to adjust for valve selection factors, multivariable hazard function analyses to identify risk factors for all-cause mortality, and bootstrap resampling to quantify the reliability of the results. RESULTS: Twenty-five percent of patients had indexed internal orifice areas of less than 1.5 cm(2)/m(2) and more than 2 SDs (Z-value) below predicted normal aortic valve size. Mechanical valve orifices were smaller (1.3 +/- 0. 29 cm(2)/m(2), Z = -2.2 +/- 1.16) than pericardial (1.9 +/- 0.36 cm(2)/m(2), Z = -0.40 +/- 1.01) or allograft valves (2.1 +/- 0.50, Z = 0.24 +/- 1.17). The overall survival was 98%, 96%, 86%, 69%, and 49% at 30 days and 1, 5, 10, and 15 years postoperatively. Univariably, survival was weakly and inversely related to manufacturer valve size (P =.16) and internal orifice diameter (P =. 2) but completely unrelated to indexed valve area (P =.6) or Z-value (P =.8). These, and univariable differences among valve types (P =. 004), were accounted for by different prevalences in patient risk factors and not by valve size or type per se. Bootstrap resampling indicated that these findings had a less than 15% chance of being incorrect. CONCLUSIONS: Survival after aortic valve replacement is strongly related to patient risk factors but appears not to be adversely affected by moderate patient-prosthesis mismatch (down to about 4 SDs below normal). Aortic root enlargement to accommodate a large prosthesis may be required in few situations.

Adolescent↗

PubMedDate not supplied

Preferred method for insertion of the Toronto Stentless Porcine Valve.

The Toronto Stentless Porcine Valve has been extensively used for aortic valve replacement. A standardized, detailed description of a preferred operative technique has been absent from the literature. A method is described that stresses (a) proper position and orientation of the aortotomy, (b) debridement of the diseased native valve, (C) proper sizing of the aortic root and choice of prosthesis and (d) implantation of the valve. Using this technique, the prosthesis can be reproducibly implanted with relative ease, without valvular insufficiency or coronary obstruction.

Aortic Valve↗

PubMed1998

The Sorin Bicarbon valve: clinical evaluation in Israel.

BACKGROUND: Four collaborating centers pooled their results with the Sorin Bicarbon Bileaflet valve. MATERIAL AND METHODS: Between 6/91 and 11/95, 431 patients, 235 males and 196 females, underwent valve replacement using the new Sorin prosthesis; age range: 16-88, mean 61.4 yrs. OPERATIONS: AVR - 206, MVR - 177, TVR - 1, DVR - 47. Additional procedures - 139: CAB -117, valve repair - 22. AV sizes: 19-27, MV sizes: 21-33. RESULTS: Thirty day mortality was 4.3%. Early complications included: CVA - 1.4%, +ve blood culture - 2%, reop for bleeding - 5%. Late complications: infective endocarditis - 2.3%, valve thrombosis - 0.2%, thromboemboli - 2.5%, major bleeding - 1.6%, reoperation - 3%, late deaths (all causes) - 4.3%. No structural deterioration has been reported with this valve and acceptable gradients have been observed. Hemolysis is negligible. CONCLUSIONS: Based on this intermediate experience the Sorin Bicarbon prosthesis is well-designed with good hemodynamic properties, and an acceptably low incidence of complications.

Aortic Valve↗

PubMed2000

CarboMedics mechanical prosthesis: performance at eight years.

BACKGROUND AND AIM OF THE STUDY: The bileaflet St. Jude Medical mechanical prosthesis has been implanted for over 20 years. The purpose of this study was to evaluate the clinical performance of the bileaflet CarboMedics (CM) prosthesis, which was introduced in 1986. METHODS: The CM prosthesis was implanted in 1,258 patients (709 males, 549 females; mean age 60.9 +/- 12.3 years) between 1989 and 1997. The prosthesis distribution was aortic valve replacement (AVR) 613; mitral valve replacement (MVR) 447; and multiple replacement (MR) 231. Coronary artery bypass (CAB) was performed in 334 (26.6%) patients; previous procedures had been performed in 346 (27.5%). The age distribution was <60 years (n = 527), 61-70 years (n = 424) and >70 years (n = 307). Risk factors assessed were age or age groups, gender, CAB, previous surgery, rhythm, valve position, status and NYHA functional class. The total follow up was 4,765.0 patient-years (pt-yr), and was 98.4% complete. RESULTS: The early mortality rate was 5.6% (AVR 4.8%, MVR 3.7%, MR 11.5%). The late mortality rate was 3.7%/pt-yr (n = 174), and valve-related mortality 1.1%/pt-yr (n = 50). The total thromboembolism (TE) rate was 4.1%/pt-yr (n = 195) (p = NS by valve position); the major TE rate was 1.9%/pt-yr and fatal TE rate 0.31%/pt-yr (n = 15). The valve thrombosis rate was 0.31%/pt-yr (n = 15; 11 MVR, four MR). The fatal thrombosis rate was 0.06%/pt-yr (n = 3; two MVR, one MR). The hemorrhage rate was 2.7%/pt-yr (n = 128) and fatal hemorrhage rate 0.4%/pt-yr (n = 20). The reoperation rate was 1.0%/pt-yr (n = 46), fatal 0.1%/pt-yr (n = 5). The actuarial freedom from overall TE at eight years was 77.3 +/- 2.8%; major TE 88.5 +/- 1.6%, and hemorrhage 76.4 +/- 3.2% (all p = NS by valve position). There were no independent predictors of overall TE and TE exclusion of early events. The only predictor for TE major was status (emergency > urgent > elective). The actuarial freedom from valve-related mortality at eight years was 91.4 +/- 1.8% (p = NS by position) (actual freedom 93.0 +/- 1.3%). The actuarial freedom from valve-related reoperation was 91.1 +/- 2.4% (p <0.05; AVR > MVR and MR, MVR > MR) (actual freedom 92.2 +/- 2.7%). Overall survival rate at eight years was 68.2 +/- 2.3% (p <0.05; AVR > MVR and MR, MVR > MR). CONCLUSION: The clinical performance of the CarboMedics mechanical prosthesis is satisfactory when implanted in the mitral, aortic and multiple positions.

Aged↗

PubMedDate not supplied

Quantification of periprosthetic valve leakage with multiple regurgitation jets by magnetic resonance imaging.

A patient with aortic prosthetic valve endocarditis required replacement of the prosthesis, After initial recovery, his left ventricular function gradually declined and echocardiography revealed minor paravalvular leakage and a cavern around the prosthesis. Magnetic resonance imaging was performed, flow-imaging and volume-based measurements showed high-grade paravalvular leakage of 45 and 58% regurgitant fraction, respectively. Intraoperatively, the dehiscence of more than half of the circumference of the aortic prosthesis was seen. This study shows that MRI can accurately assess even periprosthetic valve leakage with multiple regurgitation jets.

Adolescent↗

PubMed2003

Choice of prosthetic heart valve for adult patients.

This review summarizes the major long-term (> or =10 to 15 years) patient outcomes after insertion of many Food and Drug Administration approved prosthetic heart valves (PHV). Mechanical PHV was associated with a better survival (p < 0.02) at 15 years after aortic valve replacement (AVR) than with a bioprosthesis in the Department of Veterans Affairs (DVA) trial. In both the DVA and the Edinburgh Heart Valve trials, bioprosthesis were associated with structural valve deterioration (SVD) (mitral valve replacement [MVR] > AVR) and, therefore, for replacement of the PHV. Thromboembolism and bleeding rate were higher with mechanical PHV. Mortality after AVR and MVR is high at 10 to 15 years because of the associated comorbid conditions and older age of patients. Outcomes with "new" good valves are similar to that with "older" good valves. Complication rates of thromboembolism, bleeding, endocarditis, and leak vary widely; the rates of these complications are not different among different mechanical PHV and among different bioprosthetic PHV. Structural valve deterioration is rare with mechanical PHV. Structural valve deterioration of bioprosthesis after MVR is higher than after AVR; after AVR, homografts and bioprosthesis have similar rates of SVD. The exact rate of SVD of the pulmonary autograft is uncertain. Valve prosthesis-patient mismatch is clinically important when it is severe and in selected patients when it is moderate. Bioprosthesis have a low rate of SVD in the older patient and, thus, are the PHV of choice for AVR in patients > or =60 to 65 years of age and for MVR in patients > or =65 to 70 years of age; in younger patients mechanical valves are the PHV of choice. In individual patients there may be exceptions to these general rules.

Adult↗

PubMed2006

Wolf in wolf's clothing--a case of prosthetic aortic valve thrombosis presenting as an acute coronary syndrome.

Mechanical prosthetic valve thrombosis (PVT) is a potentially life threatening event that occurs with an incidence of 0.2% per patient year following aortic valve replacement [Lengyel M, Fuster V, Keltal M, et al. Guidelines for management of left-sided prosthetic valve thrombosis: a role for thrombolytic therapy. J Am Coll Cardiol 1997;30:1521-6]. We present the case of a middle-aged man with thrombosis of his aortic valve prosthesis mimicking an acute coronary syndrome. The patient received thrombolytic therapy with subsequent embolism of thrombotic debris to the leg.

Acute Disease↗

PubMedDate not supplied

A technique of snaring method for fitting a prosthetic valve into the annulus.

BACKGROUND: Tourniquetting technique to fit a prosthetic valve (PV) into the annulus in valve replacement surgery has been previously reported. We modified the previously reported method and designed a simpler tying technique. PATIENTS: We performed 11 aortic (AVR: including four cases for calcified aortic stenosis (AS) with a small annulus and one cases for infective endocarditis with intramuscular abscess cavity), eight mitral valve replacements (MVR), and one tricuspid valve replacement (TVR: for corrected transposition of the great arteries). TECHNIQUES AND RESULTS: A PV was implanted using 2-0 polyester mattress sutures with a pledget. Each of the two tourniquets held a suture at the bottom of the annulus and at the opposite position to fit a PV. The sutures between each snare were tied down from the bottom to the top. In MVR, after seating of a PV with two tourniquets, we could make sure that no native tissue of any preserved mitral apparatus disturbed PV leaflet motion. In calcific AS, a PV had a good fitting into the annulus because of tourniquets applied to unseated part during tying sutures. In AVR for infective endocarditis, mattress sutures supported by a Teflon pledget were placed to close the abscess cavity. After snaring on one of these sutures, we tied down the sutures, ensuring that they did not cut through the friable tissues. In TVR, we found that native leaflets interfered with PV motion after seating down the prosthesis and those leaflets were resected before tying down the sutures. Postoperative transesophageal echocardiography showed no paravalvular leakage in any patients and excellent PV functions.

Aortic Valve↗

PubMed1999

Successful dilatation of the small aortic root for implantation of a larger valve prosthesis.

Optimal hemodynamic performance is of paramount importance when implanting a prosthesis in a patient with a small aortic annulus. In order to avoid prosthesis size/patient body surface area mismatch, current techniques advocate aortic annulus patch enlargement or the use of a supra-annular prosthesis to ensure the implantation of an appropriately sized aortic valve. We present the first description of mechanical dilatation of a small aortic annulus as a simple alternative method.

Aged↗

PubMed2005

Eight-year results after aortic valve replacement with the CryoLife-O'Brien Stentless Aortic Porcine Bioprosthesis.

OBJECTIVE: The long-term durability and hemodynamics of stentless valves are largely unknown. In this study we prospectively analyzed 8-year clinical results with the CryoLife-O'Brien Stentless Aortic Porcine Bioprosthesis (CryoLife Inc, Kennesaw, Ga) and assessed its hemodynamic performance by serial echocardiography. METHODS: A total of 206 patients with a mean age of 72.8 years were followed up prospectively after aortic valve replacement with the CryoLife-O'Brien stentless bioprosthesis. Patients have been followed up from 2 to 96 months for mean 56 months. Echocardiography was performed by a single echocardiographer preoperatively, intraoperatively, postoperatively at discharge, 3 to 6 months later, and annually thereafter. RESULTS: The 30-day operative mortality was 4.8%. Sixty-five percent of patients received a valve 25 mm in diameter or larger, and 37% underwent concomitant coronary bypass grafting. Twelve late deaths, none valve-related, have occurred. Severe aortic insufficiency caused by oversizing led to early reoperation in 3 patients. The peak and mean systolic gradients decreased significantly during the first 12 months after implantation (P < .001), and the effective valve areas increased significantly during this interval (P < .001). At 8 years, 2 patients have mild to moderate aortic insufficiency. The actuarial survival at 8 years was 82% +/- 3%. The freedom from endocarditis was 100%, and the freedom from thromboembolic events was 93%. CONCLUSION: Despite more demanding surgical technique than with conventional bioprostheses, the CryoLife-O'Brien bioprosthesis can be implanted safely in a population predominantly older than 70 years at the time of the operation, with excellent measures of hemodynamics, clinical outcomes, prosthesis durability, and survival through 8 years.

Aged↗

PubMed2005

Impact of prosthesis-patient size on functional recovery after aortic valve replacement.

BACKGROUND: Prosthesis-patient size mismatch results when an implanted prosthetic aortic valve is of insufficient size for a patient's body surface area. The relation between prosthesis-patient size and functional capacity and adverse postoperative outcome is inconsistent. Our objectives were to examine the impact of valve replacement, continuous prosthesis-patient size, and other factors on functional recovery after aortic valve replacement (AVR) with the Duke Activity Status Index (DASI). METHODS AND RESULTS: From June 15, 1995, through May 14, 1998, 1108 patients underwent AVR after completing a DASI survey. Of these, 1014 completed a postoperative DASI survey at an average of 8.3 months postoperatively. Logistic ordinal regression was used to examine the influence of demographic variables, comorbidities, baseline DASI scores, indexed valve orifice area, standardized orifice size, and postoperative morbid events on postoperative DASI. There was overall improvement in postoperative functional recovery reflected by median preoperative and postoperative DASI scores of 29 and 46, P<0.001, respectively. Neither indexed orifice area, P=0.94, nor standardized orifice size, P=0.96, was associated with functional recovery. Female sex, increasing age, elevated serum creatinine, increased central venous pressure, and red blood cell transfusion were factors associated with poor postoperative functional recovery. CONCLUSIONS: A majority of patients report improvement in functional quality of life early after AVR. Similar functional recovery was demonstrated for patients along the full spectrum of valve sizes indexed to body size, even for values considered to represent severe mismatch for patient size. Factors other than prosthesis-patient size influence functional quality of life early after AVR.

Adult↗

PubMed2004

Replacement of an aortic Starr-Edwards ball valve prosthesis 28 years after implantation.

A 53-year-old woman who had undergone aortic valve replacement with a Starr-Edwards (S-E) valve (Model 1260) and open mitral commissurotomy 28 years previously was hospitalized with cardiac failure. Echocardiography showed mitral stenosis, mitral regurgitation, and a normally functioning S-E prosthesis. At reoperation, the mitral and aortic valves were replaced with St Jude bileaflet mechanical prostheses. Examination of the explanted S-E prosthesis revealed no structural abnormality other than lipid infiltration of the silastic ball.

Aortic Valve↗

PubMed1998

Small aortic annulus: a functional definition.

BACKGROUND & OBJECTIVE: Small aortic annulus is conventionally associated with poor outcome after aortic valve replacement (AVR). Contrarily, several patients have excellent follow-up results after AVR with 19, 20 or 21 size Medtronic Hall (MH) or Sorin Carbocast (SC) prostheses. This disparity prompted a relook at the semantics of a small aortic annulus. METHODS: Available survivors of isolated AVR with #19, #20 or #21 prostheses - 13 with 19 SC or 20 MH valves (Group A) and 29 with 21 SC or MH valves (Group B) were studied. Disparity between actually implanted prostheses versus predicted prosthetic size (tissue annulus diameter) was analysed according to nomograms of Rowlatt et al, NIH Plehn, Kishimoto formula and Sievers composite criteria. Preoperative and follow-up echocardiographic assessments were used for hemodynamic and prosthetic function indices. RESULTS: Both groups were similar in age, height, weight, BSA, BMI, mean NYHA class, CTR, preoperative peak gradient (PG) (92. 0 +/- 29.55 vs 102.88 +/- 33.65), mean gradient (MG) (56.8 +/- 24.6 vs 61.55 +/- 16.56), LVEDD (50.75 +/- 10.92 vs 56.0 +/- 13.5), LVESD (34.37 +/- 13.32 vs 38.52 +/- 13.85) and LVEF (67.5 +/- 12.5 vs 63.9 +/- 14.3). By developmental indices of Rowlatt et al. and NIH, no valve annulus could be designated as narrow. By Sievers composite nomogram all implanted valves were undersized by echocardiographic parameters, in normal range by angiographic criteria and oversized by anatomic autopsy data. Implanted valves in both groups were bigger than Plehn-predicted size (18.16 +/- 1.48 in GrA, 19.46 +/- 1. 10 in GrB). Valve size indices (VSI) (GrA 16.16 +/- 2.85 GrB 14.24 +/- 1.64) and geometric orifice area indices (VAI: valve area index) (GrA 1.50 +/- 0.28 vs 1.41 +/- 0.19) and postoperative rest PG (GrA 47.2 +/- 18.6 GrB 33.8 +/- 9.9) and MG (GrA 27.2 +/- 12.9 vs 19.0 +/- 9.9) were acceptable. LVEDD and LVESD regressed in both groups. LV mass indices regressed from 218.56 +/- 100.85 to 128.17 +/- 27.7 in GrA and 238.94 +/- 102.5 to 134.22 +/- 34.72 in GrB. Performance indices of implanted valves and postoperative aortic valve resistances were correlative. CONCLUSIONS: The size of the implanted prostheses per se does not denote narrowness. Patient-prosthesis mismatch may be considered if predicted prosthesis has VSI <12 mm/m2, VAI <1.31 cm2/m2 or prosthesis orifice diameter <19 mm which may indicate annular enlargement.

Adult↗

PubMed1999

Morphologic findings in explanted Hancock II porcine bioprostheses.

BACKGROUND AND AIM OF THE STUDY: Heart valve substitutes have been in use for over 30 years. Bioprosthetic heart valves have many advantages, but unfortunately suffer tissue degeneration and calcification. Many approaches, such as antimineralization treatment to prevent or delay these changes, have been tried. We present the morphologic findings from a series of Hancock II (antimineralization-treated) porcine bioprostheses. METHODS: Forty-five Hancock II porcine valve bioprostheses (16 mitral, 29 aortic) surgically explanted between March 1991 and December 1995 at the Toronto Hospital were analyzed for morphologic findings and causes of failure. The prostheses were implanted in 36 adults (mean age 55+/-14.7 years, range: 27 to 75 years) and had been in place between one month and 11 years (mean 5.1+/-3.3 years). RESULTS: Structural valve deterioration (SVD) characterized by tissue degeneration, calcification, cusp tears and increased stiffness, was the single most significant finding and cause of failure, affecting 56% of valves. Some degree of calcification was seen in 55% of prostheses, with severe calcification (grade 3 or 4) in 18%. Aortic bioprostheses showed more severe and earlier calcification than mitral ones (p = 0.03). Compared with the standard Hancock valve, the low incidence of significant calcification suggests a beneficial protective effect of antimineralization treatment. Severe pannus (grade 3 or 4) was seen in 60% of these prostheses. The pattern of pannus growth differs between mitral and aortic sites; mitral prostheses showed pannus on the flow and non-flow surfaces, often associated with cusp tears, mitral regurgitation and mitral leaflet preservation. A similar degree of pannus on aortic prostheses was invariably present on the flow surface and extended onto the valve cusps, leading to changes in the orifice which may cause clinical aortic stenosis. Infective endocarditis was seen in 15 prostheses (five mitral, 10 aortic) from 11 patients, and comprised the second most important cause of prosthesis failure. The risk of recurrent endocarditis was particularly high in patients who had infective endocarditis before valve replacement, even at five and six years post implantation. CONCLUSIONS: SVD is the major finding in explanted Hancock II bioprostheses and is associated with cusp tears and calcification. The incidence of tissue calcification appears lower at the mitral site. These findings suggest that the antimineralization treatment had some beneficial effect. Pannus associated with prosthesis dysfunction at the mitral sites is a prominent finding and on the non-flow surface may be related to the native mitral valve-conserving procedure.

Adult↗

PubMed1999

The CarboMedics "Top-Hat" supraannular prosthesis.

BACKGROUND: The CarboMedics "Top-Hat" supraannular prosthesis was designed to permit the implantation of a larger prosthesis. METHODS: Between June 1993 and November 1996, 127 patients (average age, 61.8+/-10.2 years) received a CarboMedics "Top-Hat" supraannular aortic prosthesis. The average follow-up was 15.7 months, and all surviving patients underwent echocardiographic study. This group is compared with 656 patients in whom a standard CarboMedics prosthesis was implanted and also with 2,927 patients who received other aortic prostheses. RESULTS: Using the standard and the supraannular sizers, there was an average increase of one size in favor of the supraannular prosthesis: 18.9+/-2.8 mm standard versus 20.8+/-2.6 mm supraannular (p < 0.005). For each prosthesis size (19 to 23 mm), the body surface area of the patients in whom a CarboMedics supraannular prosthesis was implanted was significantly smaller than that in those who received a CarboMedics standard prosthesis or any other model. Hospital mortality was 3.9%, and late mortality was 5.5%. The actuarial survival was 86.5%+/-3.9% at 42 months. CONCLUSIONS: Using the CarboMedics supraannular prosthesis allows implantation of a larger prosthesis compared with the standard CarboMedics prosthesis or other models. This advantage is especially important in patients with a small aortic root.

Adult↗