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At least 19 recordsLinked to original sources
PubMed1986

[Hemodynamic evaluation of the Carpentier-Edwards porcine bioprosthesis and the Hancock pericardial bioprosthesis in aortic position].

Forty-four asymptomatic patients were catheterised at Boucicaut Hospital 9.5 months after aortic valve replacement to assess the haemodynamic performances of 21 Hancock pericardial (HP) and 23 porcine Carpentier-Edwards (CE) (standard model) bioprostheses, implanted in the aortic position. Left heart catheterisation was performed from a femoral approach; the simultaneous gradient was measured by planimetry and the functional valve surface area calculated at rest and after exercise. The resting calculated surface area of the HP was greater than that of the CE bioprostheses (equation: see text). The transvalvular pressure gradient was lower in the HP than in the CE group (7.8 +/- 4 vs 15.3 cf243 6 mmHg; p less than 0.005). After exercise (15 patients) the calculated surface area increased with the increased transvalvular blood flow in both groups but at each flow rate the calculated valve surface area was greater in the HP group. The haemodynamic performance of the CE bioprosthesis is inferior to that of the HP bioprosthesis, especially in the smaller models. However, the CE bioprosthesis would seem to be mechanically more reliable in the long term than the HP bioprosthesis has since been withdrawn from the market.

Adult↗
PubMed2003

Conduit-on-valve replacement of a degenerated mitral bioprosthesis with a bioprosthesis.

Explantation of a degenerated mitral bioprosthesis with reimplantation of a new bioprosthesis is time-consuming and can be associated with several life-threatening complications. We developed a technique to simplify this procedure and avoid the complications by attaching a new bioprosthesis supported by a pericardium-covered Dacron tube to the intact stent.

Bioprosthesis↗
PubMed1997

[Stenosis of Carpentier-Edwards pericardial bioprosthesis in the tricuspid position caused by adhesion of native valve cusps to the bioprosthesis].

We experienced a case of dysfunction of Carpentier-Edwards pericardial bioprosthesis in the tricuspid position. Explanted bioprosthesis showed overgrowth of neointima from ring to cusps and adhesion to remnants of native cusps. This restricted the motion of the pericardial leaflets resulting in orifice stenosis. Care must be taken in such valve replacement by this prosthesis leaving native valve tissue.

Aged↗
PubMed1998

Hemodynamic features of the freestyle aortic bioprosthesis compared with stented bioprosthesis.

BACKGROUND: The Freestyle prosthesis is a new stentless aortic bioprosthesis. Anticipated benefits are improved hemodynamics and increased longevity. METHODS: Doppler echocardiograms were performed early and at 3 to 6 months, 1 year, and 2 years after operation in 157 patients (69 men, 88 women, aged 48 to 85 years) with this prosthesis, and results were compared with hemodynamic data in patients with Intact and Mosaic stented bioprostheses. RESULTS: Distinctive features of the prosthesis compared with stented prostheses are (1) an increase in effective orifice area (+0.15+/-0.26 cm2; p < 0.05) and a decrease in mean gradient (-3.5+/-4.0 mm Hg; p < 0.001) during the first 3 to 6 months postoperatively and stabilization thereafter; (2) a markedly lower mean gradient at 1 year after operation (average, 6+/-4 mm Hg) than in stented prostheses (Intact, 22+/-8 mm Hg; Mosaic, 12+/-6 mm Hg); (3) in contrast to stented prostheses, in vivo effective orifice areas much lower (-0.91+/-0.35 cm2) than those calculated in vitro; (4) as in stented prostheses, the indexed effective orifice area (cm2/m2) is the best predictor (r = 0.77 at 1 year) of the mean gradient after operation; and (5) similar incidence of aortic regurgitation (trivial or mild, 34% versus 29% in Intact). CONCLUSIONS: The hemodynamics of the Freestyle are very satisfactory and represent a marked improvement in comparison to stented prosthesis.

Aged↗
PubMed1991

The Carpentier-Edwards supra-annular porcine bioprosthesis: clinical performance to 8 years of a new generation porcine bioprosthesis.

The Carpentier-Edwards supra-annular porcine bioprosthesis has been utilized at the University of British Columbia since its introduction in 1982. The prosthesis was designed to improve hemodynamics with the supra-annular configuration and to reduce tissue failure with low-pressure glutaraldehyde preservation of the porcine aortic tissue. The prosthesis was inserted in 1,956 patients with 2,129 prostheses between 1982 and 1989. The mean age of the patient population was 62.7 years (range 13 to 87 years). The mean follow-up was 3.7 years per patient. The freedom from thromboembolism and antithromboembolic therapy-related hemorrhage at 8 years was 92% for aortic valve replacement (AVR), 83% for mitral valve replacement (MVR), and 92% for multiple valve replacement (MR) (p less than 0.05, AVR greater than MR greater than MVR). The freedom from structural valve deterioration was 86% for AVR, 73% for MVR, and 96% for MR at 8 years (p less than 0.05, AVR greater than MR greater than MVR). The freedom from nonstructural valve dysfunction and prosthetic valve endocarditis was not different between positions (p = NS). The freedom from valve-related mortality at 8 years was 98% for AVR, 94% for MVR, and 98% for MR (p less than 0.05, AVR greater than MR greater than MVR). The freedom from residual morbidity was not different at 8 years (p = NS). The freedom from treatment failure (valve-related mortality and residual morbidity) was 96% for AVR, 89% for MVR, and 94% for MR (p less than 0.05, AVR greater than MVR greater than MR).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

Aortic valve replacement with stentless porcine aortic bioprosthesis.

Twenty-nine patients were entered in a clinical trial on aortic valve replacement with a stentless glutaraldehyde-fixed porcine aortic valve. This bioprosthesis is secured to the aortic root by the same technique used for aortic valve replacement with aortic valve homografts. The functional results obtained from this operation have been most satisfactory. To assess the hemodynamic benefit of eliminating the stent of a porcine aortic valve, we matched 22 patients with a stentless porcine bioprosthesis for age, sex, body surface area, valve lesion, and bioprosthesis size to 22 patients who had aortic valve replacement with a Hancock II bioprosthesis. Mean and peak systolic gradients across the aortic bioprosthesis and effective aortic valve areas were obtained by Doppler studies. Gradients across the stentless bioprosthesis were significantly lower than gradients across the Hancock II valve for every bioprosthesis size. Effective aortic valve areas of the stentless bioprosthesis were significantly larger than the valve areas of the Hancock II valve. Our data demonstrate that the hemodynamic characteristics of a glutaraldehyde-fixed porcine aortic bioprosthesis are greatly improved when the aortic root is used as a stent for the valve. This technique of implantation is expected to enhance the durability of the bioprosthesis, because the aortic root may dampen the mechanical stress to which the leaflets are subjected during the cardiac cycle.

Adult↗
PubMed2005

Tubular heart valves: a new tissue prosthesis design--preclinical evaluation of the 3F aortic bioprosthesis.

BACKGROUND: It was hypothesized that native heart valves function as if they were simple tubes with sides that collapse when external pressure is applied. Because "form follows function," this hypothesis could theoretically be confirmed by implanting a simple tube into the anatomic position of any native heart valve and documenting that under the same anatomic constraints and physiologic conditions as the native valve, the tube would assume the form of that native valve. If the hypothesis were thus proved, it would follow that a tissue valve based on a tubular design would have superior flow dynamics and stress distribution and would therefore be expected to outlast currently available tissue valves. Such a tubular tissue valve, the 3F Aortic Bioprosthesis (3F Therapeutics, Inc, Lake Forest, Calif) was designed and tested in vitro against a commercially available stentless aortic bioprosthesis. METHODS: With the use of state-of-the-art testing equipment, some of which had to be developed especially to test this truly stentless bioprosthesis in vitro, transvalvular gradients, effective orifice areas, degree of transvalvular laminar flow, finite element analysis of the distribution of leaflet stress, and accelerated wear testing for long-term durability were evaluated for the new 3F Aortic Bioprosthesis in comparison with the St Jude Medical Toronto SPV aortic bioprosthesis (St Jude Medical, Inc, St Paul, Minn). RESULTS: The valve gradients were lower and the effective orifice areas were greater for the 3F Aortic Bioprosthesis at all valve sizes and under all test conditions, including cardiac outputs ranging from 2.0 to 7.0 L/min, mean perfusion pressures from 40 to 200 mm Hg, and aortic compliances of 4% and 16%. The transvalvular flow across the 3F Aortic Bioprosthesis in vitro was qualitatively smooth, with a minimum of surrounding vortices. Maximum stress occurred in the belly of the leaflets of the 3F Aortic Bioprosthesis, with minimum stress at the commissural posts. The 3F Aortic Bioprosthesis was superior to the Toronto SPV valve in accelerated wear tests. CONCLUSIONS: These in vitro studies show that a tissue aortic valve designed on the basis of the proved engineering principle that form follows function has better hemodynamics, flow dynamics, stress distribution, and durability when compared under identical in vitro conditions with an excellent commercially available tissue aortic valve.

Biomechanical Phenomena↗
PubMed2005

[Texture of mitral bioprosthesis, ventricular function and formation of thrombus. Analysis through transesophageal echocardiography and use of bioscore].

OBJECTIVE: Facing the hypothesis of participation of mechanical stress as a cause of mitral bioprosthesis dysfunction, we decided to assess the relation of preservation of the texture of the mitral bioprosthesis leaflets with left ventricular function, in addition to the casual formation of thrombus in left atrium in patients with left ventricular dysfunction from the implant of mitral bioprosthesis. METHODS: Forty 40 patients with mitral bioprosthesis through multiplane transesophageal echocardiogram were studied and divided in two groups: with left ventricular dysfunction (FE=0.40+/-0.09) since the bioprosthesis implant (20 patients: age 47.75+/-11.10 years old and surgery time 5.3+/-2.6 years) and with normal left ventricular function (FE=0.73+/-0.06) since the implant (20 patients: age 49.75+/-13.59 years old and surgery time 5.7+/-3 years). The texture of bioprosthesis leaflets was analyzed through a transesophageal echocardiographic score (FACIMT Bioscore): 1) Fusion of leaflets (score 1 to 3); 2) Apposition of tissues (score 1 to 3); 3) Calcium in leaflets (score 1 to 5); 4) Integrity of leaflets (score 1 to 3); 5) Motility of leaflets (score 1 to 4) and 6) Thickness of leaflets (score 1 to 3). The presence of thrombi in left atrium was assessed through multiplane scanning of the left atrium and left atrial appendage in the transesophageal study. RESULTS: There was no significant difference in the texture of bioprosthesis mitral position between the groups, for the total score (8.7+/-2.4 vs. 7.9+/-2.1, p=0.259), and for each analyzed item. A greater incidence of thrombi in left atrium and left atrial appendage was detected in patients with ventricular dysfunction (65% vs. 20%, p=0.004). CONCLUSION: The left ventricular dysfunction was not a protecting factor of the texture of bioprosthesis leaflets in mitral position in the tardive post-surgery period. The patients with left ventricular dysfunction showed a more favorable environment for the formation of thrombi in left atrium.

Atrial Appendage↗
PubMed2003

[Clinical and hemodynamic results of the mosaic bioprosthesis in aortic position].

INTRODUCTION: Aim of the study was to evaluate the hemodynamic and clinical performance of the Mosaic bioprosthesis in the aortic position. PATIENTS AND METHODS: The Mosaic bioprosthesis is a stented porcine heart valve for implantation in the aortic and mitral position, which combines zero pressure and root pressure fixation with glutaraldehyde, antimineralization treatment with alpha amino oleic acid (AOA) and a low profile stent, to optimize hemodynamic function and to minimize mechanical wear and thus to achieve longer tissue durability. Included in a multicenter study, 100 patients (49 females) underwent isolated aortic valve replacement with the Mosaic bioprosthesis between February 1994 and May 1999. Average age at implant was 73.4 +/- 7.3 years (range 31.3-86.8 years). Preoperative and operative clinical data are shown in Tables 1 and 2. Patients were followed-up within the first 30 postoperative days, after six months and at annual intervals, including transthoracic echocardiography and documentation of any adverse events. Mean follow-up was 3.8 years (range 0.1-7.1 years), total 383.1 patient-years. Follow-up is 100% complete. RESULTS: One year after implantation of the bioprosthesis, mean systolic pressure gradient was 15.3 +/- 6.7 mmHg (21), 14.5 +/- 5.7 mmHg (23), 12.7 +/- 4.1 mmHg (25) and 13.0 +/- 4.8 mmHg (27); effective orifice area (EOA) was 1.4 +/- 0.4 cm2 (21), 1.7 +/- 0.4 cm2 (23), 1.8 +/- 0.4 cm2 (25) and 2.6 +/- 0.4 cm2 (27) (Table 3). One year postoperative, nine patients (10.8%) showed mild aortic regurgitation and one patient (1.2%) moderate. Left ventricular mass index decreased significantly for all sizes within the first postoperative year from 159.7 +/- 56.8 g/m2 to 137.3 +/- 40.8 g/m2. Separating the patients with regard to valve size, only the 21-group (154.1 +/- 51.2 g/m2 to 129.1 +/- 34.6 g/m2) and the 27-group (237.7 +/- 59.2 g/m2 to 146.7 +/- 20.6 g/m2) showed significant results. Freedom from event rates at seven years were 96.8 +/- 1.8% for thromboembolic events, 97.2 +/- 2.0% for thrombosed bioprosthesis, 96.6 +/- 2.6% for structural valve deterioration, 98.2% +/- 1.8% for nonstructural dysfunction, 95.9% +/- 2.0% for antithromboembolic hemorrhage, 98.9 +/- 1.1% for endocarditis and 93.9 +/- 3.2% for reoperation and explant (see Table 4). Early mortality (within 30 days) was 3.0%; late mortality was 4.6%/patient-year, including a valve-related mortality of 0.6%/patient-year. Of the patients, 96.5% showed an improvement of at least one NYHA class when comparing preoperative and one year status. DISCUSSION: The hemodynamic performance and the frequency of adverse events of the Mosaic bioprosthesis in the aortic position were very satisfactory within the first seven postoperative years with excellent results, comparable to studies about other established bioprostheses and similar to the findings in other Mosaic series. Only the number of cases of antithromboembolic hemorrhage was noticeably high. One reason might be the high percentage of patients under continuous anti-coagulant therapy: Six months postoperative, still 52.2% of the patients received phenprocoumon, 6.7% acetylsalicylic acid. Concerning hemodynamics, patient-prosthesis mismatch appeared to be a common problem, especially in small valve sizes. Separating the sample in groups with EOA index < or = 0.75 cm2/m2 and EOA index > 0.75 cm2/m2 after one year, 51.6% in the 21-group had an EOA index < or = 0.75 cm2/m2, whereas it was 19.4% (23), 18.8% (25) and 0% (27) in the larger size groups. Generally, further data have to be collected to determine durability of the biological tissue, as the critical period has just started with the seventh year of the clinical trial. CONCLUSION: The Mosaic bioprosthesis proved to be a reliable and well-functioning device for aortic valve replacement, especially in larger sizes.

Adult↗
PubMed2004

[Early and late postoperative results after stentless aortic bioprosthesis implantation: experience of Heart Center, Kaunas University of Medicine].

UNLABELLED: The aim of our study was to evaluate the impact of stentless aortic bioprosthesis implantation on early and late postoperative results and hemodynamic changes. MATERIAL AND METHODS: Study group consisted of 66 patients, who received stentless aortic bioprosthesis in 1999-2003, and control group of 38 patients, randomly selected for data analysis out of 203 patients, who received mechanical aortic valve substitute during the same period at the Heart Center of Kaunas University of Medicine. Study protocol included clinical data, patients functional status and echocardiographic data pre and postoperatively up to 2 years. RESULTS: Within a stentless bioprosthesis group clinically more severe forms of aortic valve disease were present (NYHA f. cl. 3.47 vs 3.0), with concomitant ischemic heart disease (51.5% vs 36.8%), and mitral valve insufficiency (51.5% vs 21.1%). Subsequently coronary artery bypass grafting was performed in 50% of patients within a stentless bioprosthesis group vs 28.9% in a mechanical valve group, and mitral valve repair in 30.49% vs 10.5%. Aortic cross clamp time in a stentless bioprosthesis group was 89.1+/-21.3 min, compared to 74.6+/-39.5 min in a "mechanical" group. Data analysis of valve/body surface area match was in favor of stentless valves: patients with the same body surface area received one size larger stentless valves. Mortality in a "stentless" group was 4.54 vs 7.3% in mechanical group. Mean transvalvular gradients after 2 years were statistically significantly lower in a "stentless" group: 9.4+/-3.1 mmHg vs 11.1+/-4.1 mmHg. Also there was significant decrease of left ventricular mass and mass index in both groups, however it was more pronounced in the "stentless" valve group. CONCLUSIONS: Despite more advanced patient age, stages of aortic valve disease, complexity of operations including more demanding stentless bioprosthesis implantation techniques, early and late postoperative results are in favor of stentless bioprosthesis. Low and acceptable postoperative mortality, lower transvalvular gradients, optimal matching of valve and body surface area, could be achieved, which warrants more pronounced positive postoperative left ventricular remodeling: reduction of left ventricle mass and left ventricle mass index with improved pts survival.

Age Factors↗
PubMed2000

[Mosaic bioprosthesis after 5 years].

The Mosaic bioprosthesis is a stented porcine aortic valve, which combines the zero pressure differential fixation technique (by applying equal pressure to the in- and outflow ends of the valve, the aortic root is pressurized to maximize the flow area while no pressure is exerted on the leaflets) and an antimineralization treatment with alpha amino oleic acid for improved tissue durability. The device is in clinical use since February 1994. The purpose of this study was to collect intermediate term data of the Mosaic bioprosthesis in the aortic position to evaluate its clinical and hemodynamic function. From February 1994 to May 1999, 100 patients underwent aortic valve replacement with the Mosaic prosthesis at our department. There were 49 female patients, mean age at implant was 73.4 +/- 7.3 years (range 31 to 87). Concomitant procedures were done in 40%. Preoperative and operative clinical data are shown in Tables 1 and 2. When assessing the size of the bioprosthesis, it is important to use the original Mosaic sizer. Because of the possibility of the so-called supra-x placement, the specific construction of the sizer and the Mosaic valve often allow the implantation of a 1-size larger valve compared to the conventional supra-annular placement. By this a significant increase in the effective flow orifice is possible. This proceeding is depicted in Figure 1. All patients have been anticoagulated with phenprocoumon at least for 3 months postoperatively, INR was aimed at 2.5 to 3.5. Patients have been followed up prospectively, within the initial hospitalization for valve replacement, 6 months postoperatively and at annual intervals including an hematological check and transthoracic echocardiography. The mean follow-up was 2.7 years with a total follow-up of 273.7 patient years. The follow-up was 100% complete. After 5 years the mean systolic pressure gradient was 15.2 +/- 3.0 mm Hg for the 21-mm, 13.1 +/- 4.6 mm Hg for the 23-mm, 10.0 +/- 3.1 mm Hg for the 25-mm valve size, the effective orifice area 1.6 +/- 0.3 cm2 (21-mm), 1.9 +/- 0.3 cm2 (23-mm) and 2.5 +/- 0.8 cm2 (25-mm) (see Table 3). The freedom from prosthesis-related event rates, calculated according to Kaplan-Meier, at 5 years were: 97.3 +/- 1.9% for permanent neurological, 99.0 +/- 1.0% for transient neurological, 95.9 +/- 3.2% for thrombosed prosthesis, 95.6 +/- 2.2% for antithromboembolic related hemorrhage, 96.2 +/- 3.7% for structural valve deterioration, 96.9 +/- 3.0% for non-structural dysfunction, 100% for endocarditis and 92.0 +/- 4.9% for explant (see Table 4). The total operative mortality (within 30 days) was 3.0%, the late postoperative mortality was 4.4% per patient year and included a valve related mortality rate of 0.7%/patient year. In Figure 2 the survival function after aortic valve replacement is depicted, arranged in freedom from all deaths, from Mosaic-related deaths and from Mosaic-related plus sudden/unexplained deaths. Before implantation of the Mosaic bioprosthesis 95% of the patients were in NYHA Classes III and IV, whereas 6 months postoperatively 98% could be classified in NYHA Classes I and II (see Figure 3). In relation to other biological prostheses (Intact, Carpentier-Edwards Pericardial and Porcine, Hancock Modified Orifice, Biocor, Freestyle) the Mosaic bioprosthesis showed very satisfactory and predominantly better hemodynamic results than the compared stented valves and approached the performance of stentless prostheses. The freedom rates from prosthetic-related adverse events of the Mosaic bioprosthesis were at least equivalent to the compared prostheses. However, the satisfactory freedom rates, especially from structural valve deterioration, should be qualified by considering the experience that most incidences appear from the 5th year on after implantation. The clinical and hemodynamic performance of the Mosaic prosthesis has been very satisfactory during the first 5 years after clinical introduction. Further data will be necessary to confirm long-term durability.

Adult↗
PubMed1995

Durability of the Carpentier-Edwards porcine bioprosthesis: role of age and valve position.

The durability (structural deterioration-free interval) after valve implantation with the first-generation Carpentier-Edwards porcine bioprosthesis has been investigated. From 1978 through 1984, 420 patients (175 male, 245 female) underwent valve replacement with the Carpentier-Edwards standard bioprosthesis. Mean age was 50.6 years (range, 13 to 77 years). Isolated mitral valve replacement (MVR) was performed in 198 patients (47.1%), aortic valve replacement (AVR) in 136 (32.4%), and double valve replacement (DVR) in 86 (20.5%). Hospital mortality was 32 patients (7.6%), 7.5% for MVR, 5.1% for AVR, and 11.6% for DVR. Mean follow-up was 10.8 years (range, 9 to 15 years) and is 96.2% completed. Reoperation for structural deterioration was required in 143 patients. Actuarial curve free from structural deterioration at 15 years is 33.0% +/- 6.5% for MVR, 62.0% +/- 5.1% for AVR, and 44.2% +/- 8.2% for DVR (p < 0.03). Durability of the CE bioprosthesis for MVR was 101.6 +/- 34.5 months, 92.9 +/- 26.4 for AVR, and 84.3 +/- 25.3 for DVR (p = not significant). The regression logistic analysis between age at the time of surgery and durability of the bioprosthesis showed no correlation for the MVR group, but with the following predictive formula for AVR and DVR groups of patients older than 30 years" durability = 46.05 + 0.818 x age, for AVR (r2 = 0.43); durability = 15.81 + 1.122 x age, for DVR (r2 = 0.52). In conclusion, we have found a significant difference in the behavior of the CE porcine bioprosthesis between the mitral and aortic position.(ABSTRACT TRUNCATED AT 250 WORDS)

Actuarial Analysis↗
PubMed1999

Clinical and hemodynamic performance of the Freestyle aortic root bioprosthesis.

BACKGROUND: The objective of this study is to assess the clinical and hemodynamic performance of a stentless porcine bioprosthesis, the Freestyle aortic root bioprosthesis. METHODS: Consenting patients requiring isolated aortic valve or aortic root replacement received the Freestyle bioprosthesis. Clinical follow-up and echocardiographic data were obtained at discharge, 3 to 6 months, 1 year, and annually thereafter. RESULTS: Two hundred seventy-six patients received a Freestyle aortic root bioprosthesis between January 1993 and July 1997. The mean age was 67.7 years. Preoperatively, 86.3% were either New York Heart Association class III or IV. Two hundred thirty-eight patients underwent valve (subcoronary) replacement, 36 underwent aortic root replacement, and 2 underwent valve replacement using the root-inclusion technique. The early mortality was 5.4%, with 3.3% mortality for the subcoronary technique and 19.4% mortality for aortic root replacement. The mean gradient decreased significantly between discharge and the 3- to 6-month follow-up and stabilized thereafter. The effective orifice area increased significantly from discharge to 3 to 6 months' follow-up. At 3 years, 84.4% of the patients had either no or trivial regurgitation. CONCLUSIONS: The Freestyle bioprosthesis has good clinical performance and good short-term hemodynamic performance. The majority of the regurgitation identified is not clinically significant.

Adult↗
PubMed2003

The Mosaic bioprosthesis in the aortic position: seven years' results.

BACKGROUND AND AIM OF THE STUDY: The Mosaic bioprosthesis is a stented porcine aortic valve, which combines glutaraldehyde fixation with zero-pressure and root-pressure techniques and anti-mineralization treatment with amino-oleic acid for improved hemodynamics and tissue durability. The study aim was to collect intermediate-term data of the Mosaic bioprosthesis in the aortic position, the first device having been implanted in February 1994 at the authors' institution. METHODS: A total of 100 patients (49 females, 51 males) underwent aortic valve replacement with the Mosaic bioprosthesis between February 1994 and May 1999. Mean age at implant was 73.4 +/- 7.3 years. Concomitant procedures were performed in 40.0% of cases. Patients were followed up within 30 days postoperatively, after six months, and at annual intervals thereafter. Mean follow up was 3.8 years (range: 0.1-7.1 years); total follow up was 383.1 patient-years (pt-yr) and 100% complete. RESULTS: Early mortality (< or = 30 days) was 3.0%; late mortality was 4.6%/pt-yr, including a valve-related mortality of 0.6%/pt-yr. Freedom from event at seven years was 96.8 +/- 1.8% for thromboembolic events, 97.2 +/- 2.0% for thrombosed bioprosthesis, 96.6 +/- 2.6% for structural valve deterioration, 98.2 +/- 1.8% for nonstructural dysfunction, 95.9 +/- 2.0% for anti-thromboembolic hemorrhage, 98.9 +/- 1.1% for endocarditis, and 93.9 +/- 3.2% for reoperation/explant. After one year, the mean systolic pressure gradient was 15.3 +/- 6.7, 14.5 +/- 5.7, 12.7 +/- 4.1 and 12.9 +/- 4.8 mmHg for 21, 23, 25 and 27 mm valves respectively; the effective orifice area (EOA) was 1.4 +/- 0.4, 1.7 +/- 0.4, 1.8 +/- 0.4 and 2.6 +/- 0.4 cm2 for 21, 23, 25 and 27 mm valves respectively; and the EOA index was 0.8 +/- 0.3, 0.9 +/- 0.2, 0.9 +/- 0.2 and 1.3 +/- 0.1 cm2/m2 respectively. The mean left ventricular mass index was decreased significantly, from 159.7 +/- 56.8 g/m2 to 137.3 +/- 40.8 g/m2, for all valve sizes after one year. CONCLUSION: Clinical and hemodynamic performance of the Mosaic bioprosthesis was highly satisfactory during the first seven years after clinical introduction.

Adult↗
PubMed2004

Aortic valve replacement with the Cryolife-O'Brien stentless aortic bioprosthesis: five-year experience.

AIM: Improved hemodynamics with stentless bioprosthesis compared to stented valves have been well documented. It has been suggested that a simplified implant model, the Cryolife-O'Brien, offers less satisfactory outcomes compared with standard stentless models. This study was conducted to prospectively evaluate the midterm results after aortic valve replacement with the Cryolife-O'Brien stentless bioprosthesis. METHODS: In 1996, the prospective clinical trial using different stentless valves was initiated in our center. From September 1996 through August 2001, 132 consecutive patients with a mean age of 72.5 years underwent aortic valve replacement with the Cryolife-O'Brien porcine stentless bioprosthesis by the same surgeon. The predominant aortic valve lesion was stenosis in 110 cases and insufficiency in 22 cases. Patients have been followed-up from 2 to 60 months, mean 28 months. Echocardiography was performed by the same echocardiographer preoperatively, intraoperatively, postoperatively at discharge, 2 to 6 months later and annually thereafter. RESULTS: Sixty-five percent of patients received a valve 25 mm in diameter or larger, 42% had concomitant coronary bypass grafting. The 30-day operative mortality rate was 6.8 %. Nine late deaths, none related to the valve, 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<0.001) and the effective valve areas increased significantly during this time interval (p<0.001). Eleven patients have aortic insufficiency, trivial in 7 and mild in 4. The actuarial survival at 5 years was 86+/-3%. The rate for freedom from endocarditis was 100% and for freedom from thromboembolic events 92%. CONCLUSIONS: The Cryolife-OBrien stentless bioprosthesis has superior hemodynamics and a low rate of valve-related complications thus representing a very good alternative to conventional stented bioprosthesis. The midterm results are encouraging but further follow-up is needed to determine the valve's durability.

Aged↗
PubMedDate not supplied

In vitro pulsatile flow evaluation of a stentless porcine aortic bioprosthesis.

Suboptimal hemodynamic performance, tissue calcification, and limitation in long-term durability have been encountered clinically after aortic valve replacement with currently available bioprostheses. It is believed that some of these problems may be caused, directly or indirectly, by the stents of the bioprostheses. To address these deficiencies, the authors undertook the development of the Edwards Prima Stentless Bioprosthesis. This study was designed to evaluate the hemodynamic performance of the Edwards Prima Stentless Bioprosthesis in a pulse duplicator system. The stented Carpentier-Edwards Porcine Bioprosthesis (Baxter Healthcare Corp., Irvine, CA), which has been used in United States clinics for more than 10 years, was used as a control device. The flow fields in the vicinity of the test bioprostheses were inspected with color Doppler flow mapping. The transvalvular pressure gradients were measured invasively with a catheter and calculated with the Doppler determined velocity using a simplified Bernoulli equation. Additionally, the leakage volumes were determined with an electromagnetic flowmeter. In the Doppler flow mapping study, during systole, a central flow was observed distal to the stentless and stented bioprostheses. The central flow distal to the stentless bioprosthesis was broader than that observed distal to its stented counterpart. During diastole, no regurgitation was detected by color Doppler flow mapping in either the stentless or stented groups. The Doppler determined transvalvular pressure gradients correlated well with those measured by catheter (r = 0.990). Moreover, it was learned that the transvalvular pressure gradients of the stentless bioprosthesis were less than those of its stented counterpart, especially for the smaller sizes.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗