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Background: The aim of this study was to evaluate early and late outcomes after mechanical systemic heart valve replacement in pediatric patients., Methods: Between October 1981 and December 2003, 32 children (mean age 7.2 +/- 5.4 years; 4 months - 15.9 years) underwent mechanical mitral (MVR, n = 17), aortic (AVR, n = 13) or double valve replacement (DVR, n = 2) with St. Jude Medical valves. Twenty-two patients (69 %) had undergone previous cardiac surgery. Anticoagulation self-management was used since 1995., Results: The operative mortality was 3.1 %. Perioperative complications were complete heart block (n = 5), ventricular fibrillation (n = 1) and myocardial infarction (n = 1) and were exclusively related to patients with MVR. Mean calculated valve size ratio (geometric prosthesis orifice area/normal valve size area) was 1.72 (1.07 - 2.85) for AVR and 1.4 (0.88 - 3.12) for MVR. Mean follow-up was 9.1 +/- 6.6 years (range 0.4 - 23.2 years, cumulative 283 patient-years). There were two late deaths in patients with MVR. Actuarial survival after 10 years was 93.8 %. Late complications were endocarditis (n = 2), minor hemorrhagic event (n = 1), and stroke (n = 1). Anticoagulation self-management is well accepted by all patients/parents. Overall 10-year freedom from any anticoagulation-related adverse event with phenprocoumon was 89.1 % (1.2 %/patient year). Nine patients required reoperations: redo-MVR (outgrowth of prostheses (n = 3), pannus overgrowth (n = 2), closure of paravalvular leak after AVR (n = 2), partial aortic valve thrombosis (n = 1) and redo-DVR (n = 1 for endocarditis). Freedom from reoperation after 10 years was 80.9 %., Conclusions: Mechanical valve prostheses are a valuable option for left-sided heart valve replacement in pediatric patients. Perioperative morbidity was exclusively related to patients with MVR. Oversizing was often possible to avoid early reoperation for outgrowth. The operative mortality and long-term morbidity are acceptable. Anticoagulation self-management is safe and well accepted.

Mitral regurgitation is a severe problem of the mitral valve mechanism caused by many factors, including ischemic and nonischemic cardiomyopathy, inflammation, degeneration and others. Regardless of the cause of valve dysfunction, many changes in surgical approach have been undertaken. The pioneering work of Carpentier led to the era of mitral valve reconstruction a few decades ago. Understanding the different techniques applied in several pathoanatomic settings is of major interest. This review summarizes the indications and results of this specific surgical procedure in the setting of ventricular dysfunction by different causes.

Introduction: The main advantages of mitral homografts are preservation of the subvalvular apparatus and avoidance of life-long anticoagulation. In this communication, we will present our five-year experience using mitral homografts in mitral valve surgery., Patients and Methods: Since 1996, 14 patients (mean age 46 +/- 8 years, range 27 - 65 years have had mitral homografts implanted. Thirteen patients had mitral valve replacement; the septal leaflet of the tricuspid valve was replaced in one case. The indications were mitral (n = 6) or tricuspid endocarditis (n = 1), mitral valve stenosis (n = 3), and combined mitral valve disease (n = 4). Complete mitral homografts were implanted in eight patients; partial homografts were used in six cases. Preoperatively, the dimensions of the left ventricle and the mitral valve were measured by transoesophageal echocardiography (TOE). The mean left ventricular ejection fraction was 56 +/- 9%, the mean end-diastolic diameter 58 +/- 6 mm. The technique described by Acar/Carpentier was adapted for implantation; a Carpentier ring was implanted in all cases for annular stabilization. The patients had anticoagulative therapy which was discontinued when stable sinus rhythm was present after three months postoperatively. Follow-up included clinical examination, ECG, and echocardiography, and was initiated six months postoperatively and continued on a yearly basis. The following parameters were determined by echocardiography--left atrial size, left ventricular end-diastolic and end-systolic diameter, pressure gradient across the mitral valve (c/w Doppler, Bernoulli's equation), and mitral regurgitation., Results: All patients survived surgery; the mean operation-time was 281 +/- 37 minutes. Intraoperative TOE revealed a first degree insufficiency in 7 patients. Follow-up was completed in all patients, with a mean period of 30 months (6 - 60 months). Two patients had an acute endocarditis two years postoperatively, requiring repeat valve replacement with a mechanical prosthesis. An additional patient had to be reoperated due to chordal rupture three years postoperatively. All three patients had mitral valve stenosis as the initial indication for surgery and had received a complete homograft. In the remaining eleven patients, the morphological and functional state of the implanted grafts remained unchanged during follow-up. The freedom from valve-related events was 93% after one year, 86% after two years, and 79% after three years. At six-month follow-up, ECG and echocardiography revealed sinus rhythm and sufficient atrial contractions in 13 cases. At the last follow-up, the pressure gradients were 3.4 +/- 0.6 mmHg for complete homografts and 2.8 +/- 0.6 mmHg for partial homografts. In five cases, a mild insufficiency was documented, while six patients presented with competent grafts., Conclusions: Mitral homografts can be used with acceptable mid-term results in selected cases with good left ventricular function and only slightly dilated left ventricles. Partial mitral homografts represent an additional technique, especially for mitral valve repair in patients with acute endocarditis. The susceptibility to bacterial infections of a homograft makes strict prophylaxis against endocarditis mandatory.

Background: In order to minimize surgical trauma, video-assisted mitral valve operation has been started using the Port-Access technique with the addition of a three-dimensional visualization system (Vista Cardiothoracic Systems Inc, Westborough, MA) and a voice-controlled camera-holding robotic arm (Aesop; Computer Motion Inc, Goleta, CA)., Methods: Port-Access mitral valve replacement or repair (PAMVR) was undertaken using an endovascular cardiopulmonary bypass (CPB) system. Fifty patients underwent Port-Access mitral valve replacement or repair. A three-dimensional thoracoscope was inserted allowing complete three-dimensional projection of the mitral valve (Vista). In the last 20 patients, the camera was attached to a robotic arm (Aesop), which allowed stabilization and voice-activated movement of the camera. Mitral valve repair was performed in 26 patients, and the valve was replaced in 24 patients with a mechanical valve prosthesis., Results: Median time of operation was 4.2 hours, aortic cross-clamp time 83 minutes, CPB time 125 minutes, intensive care unit stay 1.5 days and hospitalization 9.0 days. Three months follow-up was complete in 40 patients, with 34 patients (85%) in New York Heart Association class I and 6 patients in class II. Mortality was 0% and rate of reoperation was 2%, with a follow-up time up to 1.5 years postoperatively., Conclusions: Using three-dimensional video and robotic assistance, it was possible to minimize the length of skin incision, but at the same time to optimally visualize the whole mitral valve apparatus in order to perform true Port-Access mitral valve operation, including various repair techniques.

Background and Aim of the Study: Mitral valve repair is superior to prosthetic valve replacement due to preservation of the subvalvular apparatus. We used cryopreserved homografts for mitral valve replacement in selected cases, in whom valve repair would not have been successful., Methods: Cryopreserved homografts were used in 10 patients (four males, six females; mean age 47 +/- 8 years; range: 27-65 years), for either complete (n = 7) or partial (n = 3) mitral valve replacement. Surgery was indicated due to acute endocarditis (n = 3), stenosis (n = 4) or combined mitral valve disease (n = 3). Transesophageal echocardiography (TEE) was performed to determine correct homograft size; these values were compared with intraoperative measurements of valvular dimensions. The function of the implanted grafts was examined intraoperatively by TEE. Follow up included clinical examination, electrocardiography and echocardiography., Results: All patients survived surgery. Intraoperative TEE revealed mild insufficiency (grade I) in six cases and no insufficiency in four. The papillary muscle-mitral annulus distance was the most reliable preoperative echocardiographic parameter to determine the required homograft. Mean pressure gradients were 3.2 +/- 0.7 mmHg for complete and 2.4 +/- 0.5 mmHg for partial homograft replacement. Sinus rhythm was present in all cases at discharge. Mean follow up was 24 months (range: 6-36 months). At six-month and one-year follow up, the pressure gradients had risen slightly to 3.4 +/- 0.6 mmHg (complete) and 2.8 +/- 0.6 mmHg (partial). To date, four patients had competent grafts, and six presented with an insufficiency (grade I). All patients had normal left ventricular function (EF 65 +/- 6%) at their last follow up; there were no signs of endocarditis during the follow up period., Conclusion: Mitral homografts for valve replacement or repair are recommended in selected cases in whom conservative reconstruction techniques are not possible. The avoidance of long-term anticoagulation therapy and preservation of left ventricular geometry are clear advantages to other mitral valve prostheses.

Introduction: Homografts for valve replacement are indicated in acute valve endocarditis. It is assumed that they possess anti-infective properties. Homografts are an established indication in aortic valve replacement. We present our early results with homografts for mitral valve replacement in acute endocarditis., Patients and Methods: Between July 1996 and March 1998 we used cryopreserved homografts for mitral valve replacement in seven patients. In three cases (age 24, 42, and 34 years) the indication was an acute endocarditis with subsequent severe mitral valve insufficiency. The size of the required homograft was measured preoperatively using transesophageal echocardiography. For implantation the technique described by A. Carpentier was used; for stabilization of the mitral anulus a valvular ring (Physio) was implanted. Follow-up was done every six months including clinical and echocardiographical examinations. After the first postoperative year an Ultrafast-CT was done in addition., Results: One patient had complete mitral valve replacement, in the other two cases the diseased parts of the valve were completely excised and the valve was repaired using a partial homograft. There were no perioperative deaths. In the follow-ups, up to 24 months of uneventful homograft function was documented by echocardiography; no insufficiency > degree I was seen on color Doppler echocardiography. At the last follow-up (mean follow-up 16 months, range 12 to 24 months) the average mitral valve orifice was 2.5 +/- 0.5 cm2, the mean pressure gradient 2.8 +/- 0.8 mm Hg. In Ultrafast-CT no morphological abnormalities of the mitral valves and no dilatation of the left ventricle were seen. There were no signs of a recurrence of the endocarditis in any patient during the follow-up period., Conclusion: Homografts for mitral valve replacement are an interesting alternative to prosthetic valve replacement, especially in younger patients. In cases with acute endocarditis, in which mechanical prosthesis should not be used, a reconstruction or repair of the mitral valve with preservation of the ventricular geometry is possible even if large parts of the mitral valve are infected.