Implante directo de válvula percutánea Edwards-SAPIEN en posición tricuspídea sobre bioprótesis degenerada en paciente con enfermedad de Ebstein / Direct Percutaneous Implantation of an Edwards-SAPIEN Valve in Tricuspid Position in a Degenerated Bioprosthesis in a Patient With Ebstein Anomaly

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MR and CT imaging of pulmonary valved conduits in children and adolescents: normal appearance and complications.

BACKGROUND: The Contegra® is a conduit made from the bovine jugular vein and then interposed between the right ventricle and the pulmonary artery. It is used for cardiac malformations in the reconstruction of right ventricular outflow tract. OBJECTIVE: To describe both normal and pathological appearances of the Contegra® in radiological imaging, to describe imaging of complications and to define the role of CT and MRI in postoperative follow-up. MATERIALS AND METHODS: Forty-three examinations of 24 patients (17 boys and 7 girls; mean age: 10.8 years old) with Contegra® conduits were reviewed. Anatomical description and measurements of the conduits were performed. Pathological items examined included stenosis, dilatation, plicature or twist, thrombus or vegetations, calcifications and valvular regurgitation. Findings were correlated to the echographic gradient through the conduit when available. RESULTS: CT and MR work-up showed Contegra® stenosis (n = 12), dilatation (n = 9) and plicature or twist (n = 7). CT displayed thrombus or vegetations in the Contegra® in three clinically infected patients. Calcifications of the conduit were present at CT in 12 patients and valvular regurgitation in three patients. The comparison between CT and/or MR results showed a good correlation between the echographic gradient and the presence of stenosis in the Contegra®. CONCLUSION: CT and MR bring additional information about permeability and postoperative anatomy especially when echocardiography is inconclusive. Both techniques depict the normal appearance of the conduit, and allow comparison and precise evaluation of changes in the postoperative follow-up.

Evolution of the Z-score in size-reduced bicuspid homografts.

BACKGROUND AND AIM OF THE STUDY: Human homografts are frequently used to establish an anatomic continuity between the right ventricular outflow tract (RVOT) and the pulmonary artery. Their limited availability, especially in small sizes, has encouraged the use of alternative strategies, such as size-reduced bicuspid homografts. The study aim was to analyze the follow up of patients who had received a standard tricuspid or size-reduced bicuspid homograft in the RVOT position, and to investigate modifications of the patients' Z-scores over the years. METHODS: A consecutive series of 107 patients aged < or = 16 years, who underwent RVOT repair between 1989 and 2010 to treat tetralogy of Fallot (ToF), was retrospectively reviewed. Of these patients, 17 received a size-reduced bicuspid pulmonary homograft, while 90 received a standard tricuspid homograft. The mean follow up periods were 10.5 years (range: 0.02-21.4 years) for the whole study population, and 11.8 years and 3.4 years, respectively, for the tricuspid and size-reduced bicuspid homograft groups. RESULTS: Freedom from mortality at 10 years was 95 +/- 3%. During the observation period, 27 patients (31%) in the tricuspid homograft group and two (125) in the size-reduced bicuspid group presented with graft failure. According to the multivariable analysis, the only independent predictor of graft failure was patient age (hazards ratio 0.86). The 17 patients who had received a size-reduced bicuspid homograft were then age-matched to an equal-sized population of tricuspid homograft patients. A comparative analysis of the time-weighted average of the Z-scores for these tricuspid and size-reduced bicuspid homograft subgroups during the follow up period failed to identify any statistical difference (p = 0.5). CONCLUSION: In terms of Z-score evolution, size-reduced bicuspid homografts offer results which are comparable to those achieved with tricuspid homografts.

Tricuspid valve replacement with a fresh antibiotic preserved tricuspid homograft.

Prosthetic replacement of valves in children is limited by size constraints of the prosthesis and lack of growth potential. In specific situations like infective endocarditis, valve preservation is near impossible and in such instances alternatives are hard to get. Furthermore, in the tricuspid position the long-term results of both mechanical and bioprosthesis are not optimal. We used an innovative method in a small boy with tricuspid valve endocarditis by using a tricuspid homograft in the tricuspid position.

Partial replacement of tricuspid valve using cryopreserved homograft.

BACKGROUND: The optimal choice of prosthesis for tricuspid valve (TV) replacement is yet to be determined. Partial replacement of the TV using a homograft atrioventricular valve might offer resistance to infection, good durability, and excellent functionality, in addition to avoiding prosthesis-related morbidity. METHODS: We present 14 patients who underwent replacement of the TV using a homograft between 1997 and 2008. The mean age at operation was 32 years, including 5 patients younger than the age of 10. All patients preoperatively showed severe TV regurgitation as a result of active infective endocarditis in 5 patients, Ebstein anomaly in 4 patients, other cardiac anomalies in 4 patients, and rheumatic valvular disease in 1 patient. The TV homograft was used in 13 patients, and mitral homograft was used in 1 patient. Eleven patients had replacement of one leaflet only, whereas 3 patients required replacement of two leaflets. Concomitant cardiac procedures were performed in 7 patients. RESULTS: No mortalities occurred during the average postoperative follow-up of 61 months (range, 12 to 126 months). Reoperation for TV regurgitation after TV repair with homograft was performed in 3 patients. The remaining 11 patients had minimal symptoms without reintervention for TV regurgitation. CONCLUSIONS: Partial replacement of the TV using a homograft provided good hospital and mid-term outcomes. This strategy might be useful in active infective endocarditis and congenital TV disease.

Video-based measuring of quality parameters for tricuspid xenograft heart valve implants.

Defective heart valves are often replaced by implants in open-heart surgery. Both mechanical and biological implants are available. Among biological implants, xenograft ones-i.e., valves grafted from animals such as pigs, are widely used. Good implants should exhibit certain typical anatomical and functional characteristics to successfully replace the native tissue. Here, we describe a video-based system for measuring quality parameters of xenograft heart valve implants, including the area of the orifice and the fluttering of the valves' leaflets, i.e., their flaps (or cusps). Our system employs automatic methods that provide a precise and reproducible way to infer the quality of an implant. The automatic analysis of both a valve's orifice and the fluttering of its leaflets offers a more comprehensive quality assessment than current, mostly manual methods. We focus on valves with three leaflets, i.e., aortic, pulmonary, and tricuspid valves.

Bicuspidized pulmonary homograft for truncus arteriosus repair.

Primary repair is preferable to palliation in infants with truncus arteriosus. At our institute, an appropriately small homograft valved conduit is not available for every patient; a bicuspidized pulmonary valve homograft is an alternative. Between December 1996 and August 2005, 24 patients aged 28 days to 21 months with truncus arteriosus underwent primary repair with a homograft valved conduit; bicuspidized homografts were used in 15 of them. In the 18 (75%) patients who survived to hospital discharge, 5-year survival was 94% (75% for tricuspid homografts and 100% for bicuspidized homografts, which was not significantly different). Freedom from reoperation or balloon angioplasty in all 18 survivors was 89% at 5 years. Freedom from reoperation in tricuspid and bicuspidized homograft groups at 5 years was 67% and 100%, respectively; the difference was not statistically significant. Bicuspidized homografts worked as well as tricuspid conduits in the intermediate term. The remodeled homografts showed excellent hemodynamic characteristics and appear to be a reasonable alternative when an appropriate size of valved homograft is unavailable.

Functional analysis of bioprosthetic heart valves.

Glutaraldehyde-treated bovine pericardium is used successfully as bioprosthetic material in the manufacturing of heart valves leaflets. The mechanical properties of bovine pericardial aortic valve leaflets seem to influence its mechanical behaviour and the failure mechanisms. In this study the effect of orthotropy on tricuspid bioprosthetic aortic valve was analysed, using a three-dimensional finite element model, during the entire cardiac cycle. Multiaxial tensile tests were also performed to determine the anisotropy of pericardium. Seven different models of the same valve were analysed using different values of mechanical characteristics from one leaflet to another, considering pericardium as an orthotropic material. The results showed that even a small difference between values along the two axes of orthotropy can negatively influence leaflets performance as regard both displacement and stress distribution. Leaflets of bovine pericardium bioprostheses could be manufactured to be similar to natural human heart valves reproducing their well-known anisotropy. In this way it could be possible to improve the manufacturing process, durability and function of pericardial bioprosthetic valves.

Mitral homograft in the tricuspid position, aortic homograft and mitral plasty in a drug addict with multiple valve endocarditis.

The case is reported of multiple valve surgery using as little prosthetic material as possible in a drug addict with recurrent right and left bacterial endocarditis. The patient underwent aortic valve replacement with a cryopreserved aortic homograft, mitral repair and tricuspid valve replacement with a mitral homograft, using a modified technique. The indications and surgical options for tricuspid valve endocarditis in this patient group are discussed, with particular focus on technical aspects of using mitral homografts in the tricuspid position.

Surgical repair for degenerative and rheumatic mitral valve disease. Operative and mid-term results.

BACKGROUND: Non randomized studies suggest that mitral valve repair for rheumatic disease is technically more difficult than repair for degenerative disease, and that operative and late results are worse. New surgical techniques have been developed in our and other institutes during the last 5 years, and this moved us to review the experience with these two pathologies and to compare the operative and mid-term METHODS: From March 1996 to September 1997, 66 patients underwent primary mitral valve repair for treatment of degenerative or rheumatic disease. Fifty-two patients (79%) were in the former group (group A) and 14 in the latter (group B). Surgery was performed by 2 experienced cardiac surgeons. A new technique to calculate the exact artificial chordae length was introduced. In 2 cases, tricuspid autografts were transposed to mitral position and reinforced with artificial chordae. Patients were followed both clinically and echocardiographically. The follow-up data were collected in a 1-month period (May 2000). The average clinical follow-up was 3.1+/-0.9 years (range 1.7 to 4.2 years) while the average echocardiographic follow-up was 2.7+/-0.7 years (range 9 months to 4 years). All values were expressed by means of the average and standard deviation. chi(2) and Student's "t"-test were used to analyze the significance between variables. The Kaplan-Meyer method was used for actuarial statistics. RESULTS: There were no operative deaths in either group. In group A, 1 patient underwent a second surgical repair 1 week later, successfully. In group B no patients underwent reoperation within 30 days or during the initial hospitalization. At follow-up of group A there were the following events: deaths from cancer (n=2), endocarditis (n=1), aortic dissection (n=1). At follow-up of group B there were mitral valve replacement (1 year after first operation, n=1), Ross procedure (n=1), ischemic heart failure (n=1). Among the remaining 62 patients followed, 32 were in NYHA class I, 15 in class II, 3 in class III, and none in class IV, in group A. In group B, 7 patients were in class I, 4 in class II, 1 in class III and none in class IV (p=ns). In group A mitral regurgitation was absent in 23 patients, mild in 21, moderate in 6, while in group B it was absent in 4, mild in 6, and moderate in 2 (p=ns). In both groups there were no cases of severe insufficiency. The mean gradient was 1.1+/-1.7 mmHg in group A (median=0), and 2.4+/-3.1 mmHg in group B (median=0), (p=ns). No case of systolic anterior movement was seen at mid-term. The event free-survival rate was 92.8% in group A and 92.3% in B. CONCLUSIONS: Perfecting and innovation of surgical techniques make possible nowadays to reach good and equivalent operative and mid-term results in both pathologies.

Tricuspid bioprosthesis replacement with cryopreserved mitral homograft.

We report the case of replacement of a dysfunctional tricuspid Hancock bioprosthesis by a cryopreserved mitral homograft. Tricuspid bioprosthesis was approached on a beating heart. The mitral homograft was orientated so as the anatomic anterior leaflets corresponding and a semi rigid prosthetic ring was inserted. At 1 year follow-up, the patient's clinical condition and echocardiographic results were satisfactory.

Is the tricuspid position suitable for testing replacement bioprosthetic valves in the sheep model?

BACKGROUND AND AIM OF THE STUDY: Glutaraldehyde may promote calcification in xenograft tissue by the action of toxic aldehyde group residues involved in the cross-link process. Post-fixation treatment with homocysteic acid (HA) neutralizes this toxicity by bonding aldehyde groups, and enhances biocompatibility on the basis of strongly electronegative sulfonic groups. Previous studies in a rat subcutaneous model showed significant long-term mitigation of mineralization of glutaraldehyde-fixed pericardium treated with HA. This study aimed to assess the anticalcific efficacy of HA in a valvular implant in growing sheep, and establish if the tricuspid position is suitable for testing replacement bioprosthetic valves. METHODS: Eleven stented 25 mm Pericarbon bioprostheses (seven HA-treated, four standard) were implanted in the tricuspid position of growing sheep. Infective endocarditis occurred in four prostheses. Among the remaining seven, three (two HA-treated, one standard) were explanted at 91 days (mid-term), and four (two HA-treated, two standard) at 140-141 days (long-term). All explants were studied by gross, X-ray, light, transmission and scanning electron microscopy, as well as by atomic absorption spectroscopy. RESULTS: No histological and ultrastructural difference in tissue preservation were observed between HA-treated and standard Pericarbon bioprostheses, either in the mid or long term. The mean calcium content of mid-term HA-treated explants was 9.55 mg/g compared with 16.26 mg/g in mid-term standard explants. Only one late standard explant failed as a result of severe stenosis caused by massive dystrophic calcification. Among four late explants, two showed significant increase in mineralization (HA-treated, 87.45 mg/g; standard, 181.20 mg/g), while two showed calcium contents similar to those in mid-term explants (HA-treated, 11.96 mg/g; standard, 17.32 mg/g). CONCLUSION: Post-fixation treatment with HA preserves structural properties after tricuspid implantation in growing sheep. The tricuspid implant in the sheep model failed to reproduce remarkable accelerated progressive calcification in all xenografts so as to demonstrate a significant difference between HA and standard explants. The tricuspid position for testing replacement bioprosthetic valves should be abandoned, and investigations repeated with the prosthesis in the mitral position.

Tricuspid autograft for repair of a destroyed mitral commissure.

The study evaluated the results of the tricuspid valve autograft technique, consisting of transferring the posterior tricuspid leaflet and subvalvular apparatus towards the mitral valve to reconstruct a destroyed commissure. Twenty patients entered the study. Etiology was degenerative in 12 patients (mean age, 55 +/- 21 years). Nine patients had endocarditis, 8 were rheumatic. Echocardiography results and secondary events were reviewed. Mean follow-up was 44 +/- 17 months. One patient died from sepsis. Survivors were in sinus rhythm. Predischarge echocardiography showed trivial or no mitral regurgitation in all but one patient (mild). Mean transmitral gradients were 3 to 6 mm Hg, and valvular surface was 4.3 +/- 2.1 cm(2). On the tricuspid valve, regurgitation was zero to mild, gradients 4 to 7 mm Hg. One patient developed recurrent endocarditis at 18 months with moderate regurgitation. Results were stable in all the other patients. The tricuspid autograft is an attractive technique for a selected group of patients with commissural destruction. The 6-year results are very encouraging.

[Partial tricuspid homograft: a new technique for tricuspid valve repair. Report of a case]. / Homogreffe tricuspide partielle: une nouvelle technique de réparation de la valve tricuspide. A propos d'un cas.

The authors report the case of a drug abuser treated successfully for fungal tricuspid endocarditis complicated by massive pulmonary embolism. Partial valvular replacement with a segment of a tricuspid homograft associated with disobliteration of a pulmonary artery was performed. Peroperative transoesophageal echocardiography showed satisfactory tricuspid valve function. The postoperative course was uneventful. After 5 months' follow-up, the patient was asymptomatic and in good general condition. Control echocardiography showed a stable operative result.