21 research outputs found
Heart failure reversal by ventricular unloading in patients with chronic cardiomyopathy: criteria for weaning from ventricular assist devices
Totally biological composite aortic stentless valved conduit for aortic root replacement: 10-year experience
<p>Abstract</p> <p>Objectives</p> <p>To retrospectively analyze the clinical outcome of a totally biological composite stentless aortic valved conduit (No-React<sup>Ÿ </sup>BioConduit) implanted using the Bentall procedure over ten years in a single centre.</p> <p>Methods</p> <p>Between 27/10/99 and 19/01/08, the No-React<sup>Ÿ </sup>BioConduit composite graft was implanted in 67 patients. Data on these patients were collected from the in-hospital database, from patient notes and from questionnaires. A cohort of patients had 2D-echocardiogram with an average of 4.3 ± 0.45 years post-operatively to evaluate valve function, calcification, and the diameter of the conduit.</p> <p>Results</p> <p>Implantation in 67 patients represented a follow-up of 371.3 patient-year. Males were 60% of the operated population, with a mean age of 67.9 ± 1.3 years (range 34.1-83.8 years), 21 of them below the age of 65. After a mean follow-up of 7.1 ± 0.3 years (range of 2.2-10.5 years), more than 50% of the survivors were in NYHA I/II and more than 60% of the survivors were angina-free (CCS 0). The overall 10-year survival following replacement of the aortic valve and root was 51%. During this period, 88% of patients were free from valved-conduit related complications leading to mortality. Post-operative echocardiography studies showed no evidence of stenosis, dilatation, calcification or thrombosis. Importantly, during the 10-year follow-up period no failures of the valved conduit were reported, suggesting that the tissue of the conduit does not structurally change (histology of one explant showed normal cusp and conduit).</p> <p>Conclusions</p> <p>The No-React<sup>Ÿ </sup>BioConduit composite stentless aortic valved conduit provides excellent long-term clinical results for aortic root replacement with few prosthesis-related complications in the first post-operative decade.</p
Comparison of diffusion-weighted with T2-weighted imaging for detection of edema in acute myocardial infarction
Perioperative echocardiographic imaging after mitral valve repair for ischemic, inflammatory, and degenerative incompetence
Recommended from our members
âCox/Maze-III-Operationâ wĂ€hrend einer Mitralklappenkonstruktion als chirurgische Therapie eines zwölf Jahre bestehenden chronischen Vorhofflimmerns: eine Fall-Vorstellung
Diese Fallvorstellung beschreibt der Verlauf einer 62jĂ€hrigen Patientin mit seit 12 Jahre bestehendem, therapieresistentem Vorhofflimmern. WĂ€hrend einer Mitralklappenrekonstruktion erhielt sie eine âCox/Maze-III-Operationâ. Zwei Jahre postoperativ befindet sie sich im stabilen Sinusrhythmus. Es bestehen weder subjektive Beschwerden noch lieĂen sich Arrhythmien im Langzeit- und Belastungs-EKG nachweisen. In der transösophagealen Echokardiographie zeigte sich eine normale HerzgröĂe und -funktion mit koordinierten atrioventrikulĂ€ren Kontraktionen, so daĂ die antikoagulative und antiarrhythmische Therapie beendet werden konnte. This case report describes a 62 years old patient who suffered from therapy resisten atrial fibrillation for 12 years. She underwent âCox/Maze-III-Procedureâ during a mitral valve reconstruction and a stable sinus rhythm was achieved. Two years after operation she has been in a stable sinus rhythm. Transesophageal echocardiography revealed normal cardiac dimensions and function with coordinated atrioventricular contractility. Therefore the therapy with anticoagulants and antiarrhythmics could be discontinued
Wear resistance and microstructure in annealed ultra high molecular weight polyethylenes
Posterior annulus shortening increases leaflet coaptation in ischemic mitral incompetence: a new and valid technique
Recommended from our members
Prognosestellung nach Implantation der intraaortalen Ballonpumpe in der Herzchirurgie
In einer prospektiven Studie wurden von 7/96 bis¶7/97, 97 Patienten mit intraoperativem low output syndrome untersucht, bei denen zum Abgang von der Herzlungenmaschine eine IABP implantiert wurde. Dabei waren 60 dieser Operationen elektiv vorgenommen worden, bei 37 FĂ€llen handelte es sich um Notfall-Eingriffe. Von den 97 Patienten verstarben 29 Patienten perioperativ. 68 Patienten konnten nach Hause entlassen werden. Patienten, die perioperativ verstarben, waren signifikant Ă€lter, hatten eine signifikant geringere LVEF prĂ€- und intraoperativ, hatten einen signifikant höheren Katecholaminbedarf trotz IABP, waren an- oder oligourisch, hatten einen signifikant geringeren cardiac index nach IABP-Implantation und hatten eine signifikant lĂ€ngere âMaschinenzeitâ als Patienten, die sich durch den Einsatz der IABP erholten. Von 5 Patienten bei denen eine Mitralklappenoperation vorgenommen worden war und bei denen perioperativ eine IABP implantiert worden war, ĂŒberlebte keiner den perioperativen Zeitraum. Wir folgern, der Erfolg oder MiĂerfolg des Einsatzes einer IABP lĂ€Ăt sich intraoperativ schon frĂŒhzeitig absehen. Bei Patienten, die trotz IABP-Einsatzes ein low output syndrome bieten, ist frĂŒhzeitig die Implantation eines ventrikulĂ€ren Assist Systems zu diskutieren. In a prospective study 97 patients with intraoperative low output syndrome, who were operated with heart-lung bypass and received an implantation of an intraaortic ballon pump, were analyzed. All operations were performed between July 1996 and July 1997. Sixty operations were elective and 37 patients were operated in an emergency situation. Twenty-nine of all patients died perioperatively. Sixty-eight patients could be discharged from the hospital. Patients who died perioperatively were significantly older, had a significantly lower LVEF pre- and perioperatively, had a higher catecholamines demand despite the IABP support, were anuric or nearly anuric, had a lower cardiac index, and the total bypass time was significantly longer. All five patients who had received mitral valve procedures died. We conclude that the success or failure of perioperative IABP support can be predicted early after implantation. In patients with low output syndrome despite the IABP support, an implantation of a ventricular assist system should be considered
Recommended from our members
Die verkalkte Aorta: Implikationen der bildgebenden Diagnostik fĂŒr Eingriffe am offenen Herzen
Zielsetzung: Verkalkungen der thorakalen Aorta können die KanĂŒlierung oder das Abklemmen der Aorta aszendens und die Anlage von aortokoronaren BypassgefĂ€Ăen erschweren oder sogar verhindern. Ziel unserer Untersuchung war es, die HĂ€ufigkeit aortaler Verkalkungen bei herzchirurgischen Patienten zu erfassen und Kriterien zu bestimmen, die operative Komplikationen vorhersagen lassen.
Methodik: In einer prospektiven Untersuchung wurden die p.a. und seitlichen Röntgen-Thoraxbilder von 100 konsekutiven Patienten (mittleres Alter: 65 Jahre, Spanne 43â87 Jahre, 34 Frauen) auf 11 Kriterien einer Aortensklerose hin untersucht. Alle Patienten waren fĂŒr einen operativen Eingriff am offenen Herzen vorgesehen. Patienten mit Zeichen einer fortgeschrittenen Aortensklerose wurden zusĂ€tzlich mit der Spiral-Computertomographie (CT) und der Echokardiographie untersucht. Die CT-Abbildungen wurden durch dreidimensionale Rekonstruktionen ergĂ€nzt.
Egebnisse: Bei 70 Patienten fanden sich Zeichen der Aortensklerose (70%). Intraoperative Komplikationen traten bei 4 Patienten ein. Bei einem Patienten konnte die geplante Operation nicht durchgefĂŒhrt werden. Alle vier Patienten zeigten im seitlichen Röntgenbild des Thorax lineare Verkalkungen der Aorta aszendens. Bei einer fĂŒnften Patientin mit computertomographisch bestĂ€tigter weitgehender Verkalkung der Aorta aszendens wurde der geplante Aortenklappenersatz wegen dieses Befundes abgelehnt. Patienten ohne lineare Verkalkungen der Aorta aszendens im seitlichen Röntgenbild konnten ausnahmslos ohne Probleme operiert werden. Die Zeichen einer Aortensklerose im p.a. Röntgenbild waren in Bezug auf operative Komplikationen weniger sensitiv und weniger spezifisch. Echokardiographisch wurde die Aszendenssklerose in vier von fĂŒnf FĂ€llen diagnostiziert, das AusmaĂ der Verkalkung jedoch in drei FĂ€llen unterschĂ€tzt. Die CT gab in allen fĂŒnf FĂ€llen die operativ gefundenen VerhĂ€ltnisse wieder.
SchuĂfolgerungen: Lineare Verkalkungen der Aorta aszendens im seitlichen Röntgenthoraxbild stellen einen hochsensitiven und spezifischen Indikator zu erwartender operativer Komplikationen dar. Die 3D-Spiral-CT ermöglicht bei solchen Patienten eine weitgehende Operationsplanung. Eine aufmerksame prĂ€operative Untersuchung herzchirurgischer Patienten auf Verkalkungen der thorakalen Aorta erlaubt es, inoperablen Patienten die Thorakotomie zu ersparen.
Purpose: Severe aortic calcification may complicate or even preclude cannulation of the ascending aorta, cross clamping, and insertion of bypass grafts. We set out to determine the incidence of aortic calcifications and to define predictors of operative complications.
Methods: In a prospective evaluation of 100 consecutive candidates for open-heart surgery, we checked the pa and lateral chest radiographs for 11 indicators of aortic calcification. Patients with severe calcification were referred for spiral computed tomography (CT) with 3-dimensional reconstruction of aortic calcifications and echocardiography.
Results: Evidence of aortic calcification was found in 70 patients (70%). In 4 patients, intraoperative complications due to aortic calcification were encountered. In one patient, surgery could not be completed. All 4 patients displayed linear calcifications of the ascending aorta on the lateral chest film. In another patient with CT proof of a completely calcified ascending aorta, aortic valve replacement was not attempted. In patients without linear calcifications of the ascending aorta, cardiopulmonary bypass could be instituted without problems. Radiographic features on the pa film were less sensitive and not specific for intraoperative complications. Echocardiography detected the lesion in 4/5 cases of severe calcification, but underestimated the extent of disease in 3 patients. CT predicted the intraoperative findings accurately in all 5 cases.
Conclusions: Linear calcification of the ascending aorta on lateral chest radiographs is a both sensitive and specific predictor of intraoperative complications. 3D spiral CT facilitates surgical planning in such pateints. Careful preoperative screening may help to avoid exposing inoperable patients to the risk of thoracotomy
A comparison and classification of grading approaches used in engineering education
Grades are intended to communicate achievement associated with a learning experience. Engineering educators in higher education often default to a particular grading approach without considering how the approach impacts student achievement. This work proposes a model for comparing and classifying commonly used grading systems in engineering higher education. Examples from the engineering education literature revealed five general categories of grading: 1) normative, score-based grading, 2) summative grading, 3) standards-based grading, 4) mastery-based grading, and 5) adaptive grading. (Note: variations in naming conventions were observed.) Each grading system was examined to determine key characteristics of the system and how student performance was ultimately assessed. A continuum of grading approaches was created after discovering that each system ranged in its intention to select and/or develop talent. The most widely adopted approaches to grading in engineering higher education, norm-based grading, were classified using purely selective processes (e.g., letter grades). Alternative, learning outcomes-based grading approaches differentiate themselves by the level in which they attempt to develop talent. This was determined by examining differences in how the grading system impacted sequencing of content, course pace, number of attempts to demonstrate achievement, scale and weight of performance, feedback provided, and basis for a final grade. The resulting continuum provides a tool for engineering educators to compare and discuss grading approaches in order to select an appropriate system for their course or program. Informed decisions on grading can have a critical impact in student retention and program improvement