Biomedical subjects

T Walther

Publications and source records attributed to T Walther.

At least 91 records · Page 5Linked to original sources

PubMed1999

Stentless tricuspid valve replacement.

Stentless tricuspid valve replacement was performed in a 21-year-old patient with severe destructive tricuspid valve endocarditis resistant to medical therapy. Postoperative recovery was uneventful. Stentless atrioventricular valves are considered an additional treatment option besides stented valves or homograft implantations for severe right-sided endocarditis. Transvalvular hemodynamics are excellent, and right ventricular function can be preserved by suspending the valve at the papillary muscles.

Adult↗

PubMed1999

Transabdominal endoscopic computer-enhanced coronary artery bypass grafting.

BACKGROUND: Due to limited range of motion, endoscopic multivessel revascularization is difficult through a thoracic approach. METHODS: A computer-enhanced surgical telemanipulation system was used to perform transabdominal endoscopic grafting (TCAB) in an experimental cadaver model. After incising the membranous portion of the diaphragm, pericardium, and pleura, dissection of the left (n = 10) and right internal thoracic arteries (n = 5) was performed. Coronary anastomoses were performed remotely and unassisted. In an animal model the hemodynamic consequences of the approach were assessed. RESULTS: In all cadavers TCAB was achieved through three abdominal ports. Time for internal thoracic arteries harvest was 48+/-13 minutes (left) and 39+/-10 minutes (right). Intimal dissection was found in one graft. Time for anastomosis was 23+/-9 minutes and 27+/-10 minutes for the left anterior descending (n = 10) and right coronary artery (n = 5), respectively. All anastomoses were patent. Opening the diaphragm in living animals led to a decrease of systolic blood pressure by 30+/16 mm Hg, but resolved with appropriate treatment. CONCLUSIONS: TCAB is possible in cadavers using computer-enhanced telemanipulation technology. The transabdominal approach is a promising access for less invasive cardiac surgery.

Animals↗

PubMed1999

Aortic root reconstruction with preservation of native aortic valve and sinuses in aortic root dilatation with aortic regurgitation.

BACKGROUND: We assessed the results of a modified technique for aortic root reconstruction including preservation of the native aortic valve and sinuses. METHODS: A modified technique for reconstruction of the aortic root was devised in which the native aortic sinuses are preserved and remodeled, the diameter of the sinotubular junction is reduced, the ventriculoaortic junction is reinforced with a Dacron prosthesis, and the coronary ostia are reimplanted. Since January 1995, this modified operative technique was performed in 13 patients with a mean age of 54 +/- 21 years. The median grade of aortic regurgitation was 3; in 10 patients it was caused by dilatation of the sinotubular junction, and 3 had additional annuloaortic ectasia. RESULTS: The aortic crossclamping time was 61 +/- 18 minutes. In-hospital mortality was 2 of 13 (15. 3%) patients, both deaths being related to complications of aortic dissection. In 1 patient aortic regurgitation increased to grade 3, necessitating aortic valve replacement. At a mean follow-up of 2.1 years, the remaining 10 patients had stable aortic valve function with a median grade of regurgitation of 1. The mean New York Heart Association functional class was 1.2. CONCLUSIONS: Aortic root reconstruction with preservation of the native aortic valve and sinuses allows symmetric reconstruction of the aortic sinuses and adaptation of the diameters of the sinotubular and ventriculoaortic junctions, thus optimizing aortic valve function. Moreover, it prevents contact of the aortic valve leaflets with the Dacron graft, which may enhance the durability of the repair.

Adolescent↗

PubMed1999

C-type natriuretic peptide levels in women with gestational hypertension and preeclampsia.

OBJECTIVE: To measure plasma levels of C-type natriuretic peptide in women with normal pregnancies and those complicated by gestational hypertension and preeclampsia. METHODS: We collected venous plasma samples from 20 women with normal pregnancies, 15 with gestational hypertension, and nine with preeclampsia. Gestational ages ranged from 26-39 weeks. We measured C-type natriuretic peptide concentrations by radioimmunoassay. Statistical comparisons were made by one-way analysis of variance and Tukey test. RESULTS: The mean plasma concentration of C-type natriuretic peptide in the women with normal pregnancy was 7.1 +/-2.5 pg/mL, in those with gestational hypertension 9.6+/-4.2 pg/mL, and in those with preeclampsia 8.1+/-2.4 pg/mL. There were no statistically significant differences between groups. The statistical power to detect a difference of 3 pg/mL at the 5% significance level was 78% for the group with gestational hypertension and 64% for the preeclamptic group. CONCLUSION: Our results suggest that C-type natriuretic peptide plasma levels are not significantly different in normal pregnancies and those complicated by gestational hypertension or preeclampsia. In hypertensive pregnancy disorders, C-type natriuretic peptide showed a distinct course compared with atrial natriuretic peptide and brain natriuretic peptide.

Adult↗

PubMed1999

Learning and anxiety in angiotensin-deficient mice.

Angiotensin II in the brain was shown to be involved in mechanisms influencing cardiovascular and electrolyte homeostasis, anxiety and learning. Here, we report behavioural studies in mice lacking angiotensinogen. We analysed learning and anxiety related behaviour using the Morris water maze task and the elevated plus maze task, respectively. In both tests no differences were found between control mice and angiotensin-deficient mice. This implicates that angiotensin does not influence learning and anxiety-related behaviour in mice under normal conditions.

Angiotensin II↗

PubMed1999

mRNA quantification of C-type natriuretic peptide in brain areas of rodents.

C-type natriuretic peptide (CNP) is regarded as an endothelium-derived vasodilator and might therefore have an important role in controlling vascular tone and remodeling. Because CNP also is expressed in the brain, it is considered to be a neurotransmitter. The present study compares expression levels of CNP mRNA in distinct areas of the mouse brain with the expression pattern in the rat brain. A distinct expression of CNP was found in all investigated areas with the exception of the mouse striatum. In both rodents, high CNP expression was detected in the tegmentum.

Animals↗

PubMed1999

Quality of computer enhanced totally endoscopic coronary bypass graft anastomosis--comparison to conventional technique.

OBJECTIVE: Aims of the study were to develop an endoscopic technique to perform robot assisted coronary anastomoses, using a computer enhanced telemanipulator and to compare the quality of the anastomoses with those performed using a standard open technique. METHODS: A surgical telemanipulator with two instrument arms and a central videoscopic arm was used to perform remote endoscopic coronary artery bypass grafting on isolated porcine hearts. The end effectors and the videoscope were placed through three 10 mm port incisions. All anastomoses (Cx to LAD) were performed using a double armed 7-0 Prolene suture of 5 or 7 cm in length. All operations were performed remotely from the master console using ten times magnification, tremor filtering and 3:1 motion scaling. Initially 20 anastomoses were performed to develop and train the technique. Then, 20 robot-assisted anastomoses (group I) were compared with 20 anastomoses using a standard open parachute technique (group II). All anastomoses were checked for patency and leakage. Patency was confirmed by bench angiography. After fixation, all anastomoses were macroscopically evaluated for patency, intactness, alignment, intimal tears and dehiscence. Both angiographic and pathologic evaluations were performed with the examiners blinded to the technique of anastomosis. RESULTS: In the initial feasibility series, time for anastomosis was 18.2 +/- 9.1 min. All anastomoses were patent although minor stenoses were found in two and minor leakage was noted in five anastomoses. In the second series all anastomoses were patent, not leaking and showed a good run-off at angiography. Mean time for anastomosis in group I was 12.8 +/- 2.4 min as compared with 6.3 +/- 0.2 min in group II (P < 0.001), respectively. Macroscopic analysis demonstrated equal quality for both groups. There were no stenoses, no intimal tears and no dehiscences. All anastomoses had a normal alignment and intact suture lines. CONCLUSION: Using the Intuitive surgical telemanipulator, it is possible to remotely perform endoscopic coronary anastomoses with the same quality as with an open standard technique after a brief learning curve. This will enable true endoscopic coronary artery bypass grafting with a precision that has not been achieved with any other previously applied endoscopic technique.

Anastomosis, Surgical↗

PubMed1999

The evolution of minimally invasive valve surgery--2 year experience.

OBJECTIVES: The aim of the study was to evaluate the evolution of Port-Access minimally invasive mitral valve surgery to a robot assisted video assisted solo surgery approach. METHODS: One hundred and twenty-nine patients with non-ischemic mitral valve disease underwent 3D-video assisted mitral valve surgery via a 4 cm right lateral minithoracotomy using femoro-femoral bypass and endoaortic clamping. Transcranial Doppler and continuous transesophageal echocardiography were used to monitor placement and positional stability of the endoclamp. After the initial series (group I, n = 62), a simplified solo surgical technique using voice controlled robotic assistance for videoscope guidance was used in the last 67 patients (group II). RESULTS: After an initial learning curve and modifications of catheter design, the procedure could be steadily redefined and simplified. In the last 67 patients, the procedure was completed without the need for an additional assistant as 'solo surgery'. The mitral valve was repaired in 72 and replaced in all other patients. Duration of bypass and clamp time steadily improved during our study and in the most recent 67 patients average 107 +/- 34 and 48 +/- 16 min, respectively. The voice controlled robotic arm (AESOP 3000, Automated Endoscope System for Optimal Positioning) provided a stable and precise video image with excellent exposure of all valvular and subvalvular structures. Hospital mortality was high in the early series (mean survival 88.7% at 804 +/- 35 days; 95% CI: 735-873) and partially procedure related (aortic dissection in two patients). In group II, hospital mortality has declined to 3.0% (mean survival 97.0% at 568 +/- 12 days; 95% CI: 553-600). CONCLUSION: Port-Access minimally invasive mitral valve surgery has evolved to be a reliable video assisted technique with reproducible results. Surgery can now be performed almost in the same time as with conventional techniques. Robotic assistance has enabled a solo surgery approach.

Aged↗

PubMed1999

Indication and patient selection in minimally invasive and òff-pump' coronary artery bypass grafting.

BACKGROUND: The selection criteria to perform 'off-pump' coronary bypass (OPCAB) grafting are not well defined. The aim of this presentation is to outline the indications and the patient selection on the basis of 2 years experience with 572 OPCAB procedures. MATERIALS AND METHODS: From November 1996 minimally invasive coronary bypass grafting was performed in 406 patients using a limited minithoracotomy for single left anterior descending artery (LAD) revascularization (group A). In 166 patients full sternotomy and OPCAB grafting for single or multiple vessel revascularization was performed (group B). RESULTS: In group A the procedure could be performed 'off-pump' together with a limited thoracotomy in 406 out of 457 patients (88.8%) who were scheduled for single graft revascularization to LAD. Exposure and quality of the LAD was good in 308/406 (76.0%) of the patients. The decision for sternotomy was made for different preoperative characteristics of these patients: Obese female patients 16/457 (3.5%), angiographic evidence of an intramyocardial running LAD 6/457% (1.4%), diffusely diseased and small LAD 11/457 (2.4%) severe COPD 3/457 (0.7%), unstable angina 11/457 (2.4%), emergency revascularization after failed PTCA 4/457 (0.8%). In 315/406 (77.8%) of the minimally invasive direct coronary artery bypass (MIDCAB)-patients exposure and quality of the LAD was good, in 97/406 (22.2%) moderate or even bad. In the latter subgroup stenosis free anastomosis was reduced (86.5%) compared to the subgroup of good exposure and quality with 98.3%. In group B selection for sternotomy and 'off-pump' procedure was made in 117/166 (70.4%) patients with a normal preoperative status (stable angina, ejection fraction > 35%) and with coronary lesions amenable for beating heart surgery (proximal RCA lesion > 80%, not calcified and well defined POD and marginal branches). In 49/166 (29.5%) decision for 'off-pump' procedure was made on the basis of a potential risk for cardiopulmonary bypass (CPB) such as acute myocardial infarction in 10/166 (6.0%), reduced ventricular function with EF < 35 in 28/166 (16.9%), calcified ascending aorta 4/166 (2.4%) or concomitant diseases 7/166 (2.5). CONCLUSION: To maintain excellent results after single LAD revascularization using the MIDCAB-approach, appropriate patient selection is crucial. Indication for sternotomy and 'off-pump' single LAD revascularization should made in those patients excluded for MIDCAB and in patients scheduled for multiple vessel-CABG who are at high risk for CPB (concomitant pulmonary, renal, neurological diseases or severely impaired left ventricular dysfunction) and have suitable target coronary arteries in term of location and quality.

Adult↗

PubMed1999

Computer-enhanced mitral valve surgery: toward a total endoscopic procedure.

The aim of the study was to develop a computer-enhanced, video-assisted approach for mitral valve repair as a potential step toward a complete endoscopic procedure. In 10 patients with nonischemic mitral valve insufficiency, computer-enhanced telemetric mitral valve repair using the Intuitive surgical telemanipulation system was performed. A femorofemoral bypass was initiated using Port-Access (Heartport, Redwood City, CA) cannulation. A small minithoracotomy was made in the right 4th intercostal space, and a custom-made rib retractor was placed. The pericardium was opened manually, and four traction stay sutures were placed to enhance exposure. After endoaortic balloon clamping, the left atrium was opened and stabilized. The end-effectors were placed in the left atrium through two ports (3rd ICS and 6th ICS, midaxillary line). A 30 degrees three-dimensional (3D)-videoscope angled up was placed through the incision. Mitral valve repair was then performed remotely from the surgical console. This included inspection of the valve, leaflet resection, leaflet repair, and ring implantation. After completion of the repair and testing of the valve, the end effectors were withdrawn, and the left atrium was closed manually using standard endoscopic instruments (Heartport). In all but 1 patient, successful repair, including quadrangular resection, chordal shortening, Whooler-plasty, and Alfieri-plasty, could be accomplished using the computer-enhanced telemanipulation system. A partial ring was implanted in 6 patients and a complete ring was implanted in 3 patients, respectively. Time for surgery, CPB, and clamp time were 170 to 330 minutes (median, 185 minutes), 140 to 220 minutes (median, 149 minutes), and 78 to 133 minutes (median, 94 minutes), respectively. In one patient, intraoperative transesophageal echocardiography (TEE) showed insufficient repair, a second surgery was performed via an enlarged left thoracotomy. One patient with recurrent mitral insufficiency had to have a second surgery on postoperative day 3 for a torn-out ring. Median time of hospitalization was 8 days. At 3 months follow-up (completed in 7 patients), all patients had improved clinically. Computer-enhanced mitral valve repair is feasible and can be performed with good functional results. The telemanipulation system offers the potential for true endoscopic mitral valve repair. However, surgical time is prolonged, and a learning curve has to be overcome.

Aged↗

PubMed1999

Coronary bypass grafting without cardiopulmonary bypass--technical considerations, clinical results, and follow-up.

BACKGROUND: Coronary bypass surgery can be performed less invasively by avoiding cardiopulmonary bypass (CPB). We present our early 'off pump' coronary bypass surgery experience in combination with a minithoracotomy or sternotomy. METHODS: Between 11/1996 and 12/1997 312 patients were included in a prospective study, 223 (Group A) underwent an antero-lateral minithoracotomy (MIDCAB) and 89 (Group B) had a full sternotomy (OPCAB). ITA harvesting and anastomosis was performed under direct vision in all cases. Different devices for local mechanical immobilization were used to perform the anastomosis. RESULTS: In 212 patients of group A revascularization was by a single ITA graft and in 11 patients by a double graft using the radial artery as a T graft. Conversion to sternotomy and cardiopulmonary bypass was necessary in 12 (5.3%) patients. Intraoperative myocardial infarction was observed in 5 patients (2.2%). Early-postoperative reoperation due to graft failure was necessary in 5 patients (2.2%). Mortality was 0.4% (one patient). The early postoperative graft patency rate was 97.1% as confirmed by angiography. In group B, 25 patients had single graft and 64 patients multiple graft revascularization. Intraoperative conversion to CPB was necessary in 10 patients (11.2%). Intraoperative myocardial infarction occurred in 1 patient (1.1%), postoperative low output syndrome in 2 patients (2.2%). Early postoperative reoperation due to graft failure was necessary in 1 patient (1.1%). Mortality was 1.1%. Angiographic control of 48 patients after 6 months confirmed a patency rate of 92.6%. CONCLUSION: Coronary bypass surgery without using cardiopulmonary bypass is safe to achieve good early and mid-term results. MIDCAB is a minimally invasive technique. Experienced surgeons should be ready to compete with PTCA techniques.

Cardiopulmonary Bypass↗

PubMed1999

Effectiveness of different anticalcification treatments for stentless aortic bioprostheses.

BACKGROUND: New anticalcification treatments for stentless bioprostheses have not yet been compared independently. MATERIAL AND METHODS: The No-reacts (Biocor), AOA (Medtronic Freestyle), and BiLinx (SJM Toronto SPV II) methods were studied and compared with a control group. Aortic valve leaflet and aortic root tissue was subcutaneously implanted in 60 male, 21-days-old Sprague-Dawley rats. Calcium content was quantified using inductively coupled plasma spectrophotometry. RESULTS: No infections occurred. Low levels of calcium were measured in aortic valve leaflet tissue for all methods (0.4 to 1.5 mg/g dry weight) in comparison to the control group (225 mg/g), p < 0.01. Calcification of aortic root tissue was low in the Bilinx group (2.4 mg/g, p < 0.01), whereas calcium levels were high in all other groups (104 to 127 mg/g). CONCLUSIONS: Calcification of aortic valve leaflets was significantly reduced by all new anticalcification treatments, whereas aortic root calcification was only reduced by inhibition of cellular calcification (BiLinx). Maximum anticalcification properties of both leaflet and aortic root are important, as these are considered a functional unit in stentless bioprostheses.

Aluminum Chloride↗

PubMed1999

Quadrileaflet stentless mitral valve replacement.

BACKGROUND: The study evaluates clinical results and hemodynamic parameters one year after implantation of a stentless quadrileaflet mitral valve (QMV). METHODS: Since August 1997 28 patients received the QMV, patient age was 69 +/- 8 years; 13 had predominant mitral stenosis and 15 incompetence, preoperative NYHA functional class was III or IV and cardiac index 1.8 +/- 0.6 L/min/m2. RESULTS: Surgery was performed using a conventional (25) or a minimally invasive approach (3). 20 patients received a medium and 8 a large-size prosthesis, crossclamp time was 58 +/- 19 min. Additional procedures were myocardial revascularization in four, tricuspid repair in two, and left-atrial radiofrequency ablation to restore sinus rhythm in six patients. Perioperative mortality (1) was not valve-related. All other patients were discharged on time. At postoperative, 6-, and 12-months follow-up mean transvalvular pressure gradients were 4.2 +/- 1.5 / 4 +/- 0.9/ 3.8 +/- 1.4 mmHg and mitral valve orifice area index was 1.5 +/- 0.3 / 1.6 +/- 0.3 / 1.6 +/- 0.4, NYHA class was I or II. CONCLUSIONS: The QMV is well suited for mitral valve replacement. The anulo-ventricular continuity is preserved and the QMV function resembles native mitral valve function. If its performance is maintained in the long term the QMV may be the mitral prosthesis of choice.

Aged↗

PubMed1999

Larger anastomoses in angiotensinogen-knockout mice attenuate early metabolic disturbances after middle cerebral artery occlusion.

Abnormalities in the homeostasis of the renin-angiotensin system have been implicated in the pathogenesis of vascular disorders, including stroke. The authors investigated whether angiotensinogen (AGN) knockout mice exhibit differences in brain susceptibility to focal ischemia, and whether such differences can be related to special features of the collateral circulation. Wild-type and AGN-knockout mice were submitted to permanent suture occlusion of the middle cerebral artery (MCA). The collateral vascular system was visualized by systemic latex infusion, and the ischemic lesions were identified by cresyl-violet staining. The core and penumbra of the evolving infarct were differentiated by bioluminescence and autoradiographic imaging of ATP and protein biosynthesis, respectively. In wild-type mice, mean arterial blood pressure was 95.0 +/- 8.6 mm Hg, and the diameter of fully relaxed anastomotic vessels between the peripheral branches of the anterior and middle cerebral arteries 26.6 +/- 4.0 microm. In AGN knockouts, mean arterial blood pressure was significantly lower, 71.5 +/- 8.5 mm Hg (P < .01), and the anastomotic vessels were significantly larger, 29.4 +/- 4.6 microm (P < .01). One hour after MCA occlusion, AGN-knockout mice exhibited a smaller ischemic core (defined as the region of ATP depletion) but a larger penumbra (the area of disturbed protein synthesis with preserved ATP). At 24 hours after MCA occlusion, this difference disappeared, and histologically visible lesions were of similar size in both strains. The observations show that in AGN-knockout mice the more efficient collateral blood supply delays ischemic injury despite the lower blood pressure. Pharmacologic suppression of angiotensin formation may prolong the therapeutic window for treatment of infarcts.

Acute Disease↗

PubMed1999

Expression of low density lipoprotein receptor messenger ribonucleic acid in placentas from pregnancies with intrauterine growth retardation.

The low density lipoprotein receptor plays an important role in the uptake of maternal plasma lipoproteins for placental steroid metabolism. Using an RNase protection assay, the expression of low density lipoprotein receptor mRNA was measured in human placentas from pregnancies in the second and third trimester and from pregnancies with intrauterine growth retardation. Pregnancies complicated by intrauterine growth retardation showed a significantly higher expression (1.28), compared with the term and preterm pregnancies (P < 0.05). The increased low density lipoprotein receptor expression in placentas from pregnancies with intrauterine growth retardation could be a compensatory mechanism for the lower circulating low density lipoprotein concentrations in women with intrauterine growth retardation.

Female↗

PubMed1999

Quality assessment in minimally invasive coronary artery bypass grafting.

OBJECTIVES: The most important determinant for the success of minimally invasive coronary artery bypass grafting (MIDCAB) is the quality and long-term patency of the graft and anastomosis. Intra and postoperative quality assessment is important to confirm the safety and effectiveness of minimally invasive techniques. METHODS: From January to December 1998 MIDCAB was performed in 246 patients using a limited minithoracotomy for single left anterior descending artery (LAD) revascularization. According to our standard protocol quality assessment of the graft and anastomosis consisted of intraoperative flow measurement, early postoperative angiography and follow-up angiography after 6 months. RESULTS: Intraoperative flow measurement was performed in patients with anastomoses unsuitable for coronary probing (75/246, mean flow of 34.3 +/- 17.7 ml/min). Early patency was confirmed by intraoperative monoplane angiogram in 37/246 (15.0%) patients and by postoperative multiplan angiography in 205/246 (83.3%). Early patency rate was 98.0%. Six months follow-up showed a patency rate of 97.5% (one occluded graft, two severe and two moderate stenoses at the anastomotic site). Eighty-nine percent of the patients were in a CCS angina class I, 11% in class II, respectively. Six months mortality was 0.8%. Re-intervention had to be performed in 5/116 (4.3%). CONCLUSIONS: A standardized protocol for quality assessment is mandatory for MIDCAB surgery. The proposed algorithm serves to ensure the safety and effectiveness of this new technique. Our recent series document an excellent outcome of the MIDCAB approach. Postoperative multiplan angiography is the only technique to achieve valid information about the quality of graft and anastomosis.

Blood Flow Velocity↗

PubMed1999

Regression of left ventricular hypertrophy after stentless versus conventional aortic valve replacement.

The goal of this study was to analyze regression of left ventricular hypertrophy after randomization to conventional biological versus stentless aortic valve replacement. Stentless (Freestyle, Toronto, n = 106) or conventional biological aortic valves (Carpentier-Edwards, n = 74) were evaluated prospectively. Preoperatively there were no differences with regard to aortic valve pathology, left ventricular function, and pressure gradients between the two patient groups. The patient annulus index (13.55 vs. 13.46 mm; NS) measured intraoperatively was used as baseline for further comparison. Postoperatively, left ventricular mass index was 213+/-77 g/m2 (stentless) compared with 202+/-72 (conventional group) g/m2 (NS), whereas after 6 months it was 141+/-41 g/m2 in the stentless and 170+/-43 g/m2 in the conventional group (P<.05). Regression of left ventricular hypertrophy occurs in all patients after aortic valve replacement. Nevertheless, the use of stentless bioprostheses leads to a significant enhancement, which may result in a reduction of the cardiac risk profile for the patient.

Aged↗

PubMed1999

Stentless mitral valve replacement using the quattro valve.

This study analyzed early clinical results after stentless mitral valve (Quadrileaflet Mitral Valve (QMV)/Quattro) implantation. A total of 28 patients have received a Quattro valve since August 1997. Patient age was 69+/-8 years; the underlying disease was mitral incompetence (14) and stenosis (13). Preoperative New York Heart Association functional class was 3.2+/-0.4 and cardiac index was 1.8+/-0.6. Mean cross-clamp duration was 58+/-19 minutes. Twenty patients received a 28-mm prosthesis, and eight patients received a 30-mm prosthesis. Four patients had myocardial revascularization, two had tricuspid valve repair, and six had radiofrequency ablation therapy to restore sinus rhythm. Mortality (1) was nonvalve related. Reoperation was necessary in two patients for posterior paravalvular leakage (1) and for functional stenosis (1). Echocardiography showed satisfactory hemodynamic function. By stentless mitral valve implantation the annuloventricular continuity is preserved to stabilize left ventricular function. The Quattro valve resembles native mitral valve function and is well suited for mitral valve replacement.

Aged↗