139 research outputs found
Double left ventricular pacing following accidental malpositioning of the right ventricular electrode during implantation of a cardiac resynchronization therapy device
Effects of autologous bone marrow stem cell transplantation on beta-adrenoceptor density and electrical activation pattern in a rabbit model of non-ischemic heart failure
BACKGROUND: Since only little is known on stem cell therapy in non-ischemic heart failure we wanted to know whether a long-term improvement of cardiac function in non-ischemic heart failure can be achieved by stem cell transplantation. METHODS: White male New Zealand rabbits were treated with doxorubicine (3 mg/kg/week; 6 weeks) to induce dilative non-ischemic cardiomyopathy. Thereafter, we obtained autologous bone marrow stem cells (BMSC) and injected 1.5–2.0 Mio cells in 1 ml medium by infiltrating the myocardium via a left anterolateral thoracotomy in comparison to sham-operated rabbits. 4 weeks later intracardiac contractility was determined in-vivo using a Millar catheter. Thereafter, the heart was excised and processed for radioligand binding assays to detect β(1)- and β(2)-adrenoceptor density. In addition, catecholamine plasma levels were determined via HPLC. In a subgroup we investigated cardiac electrophysiology by use of 256 channel mapping. RESULTS: In doxorubicine-treated animals β-adrenoceptor density was significantly down-regulated in left ventricle and septum, but not in right ventricle, thereby indicating a typical left ventricular heart failure. Sham-operated rabbits exhibited the same down-regulation. In contrast, BMSC transplantation led to significantly less β-adrenoceptor down-regulation in septum and left ventricle. Cardiac contractility was significantly decreased in heart failure and sham-operated rabbits, but was significantly higher in BMSC-transplanted hearts. Norepinephrine and epinephrine plasma levels were enhanced in heart failure and sham-operated animals, while these were not different from normal in BMSC-transplanted animals. Electrophysiological mapping revealed unaltered electrophysiology and did not show signs of arrhythmogeneity. CONCLUSION: BMSC transplantation improves sympathoadrenal dysregualtion in non-ischemic heart failure
The phenomenology of the mathematics classroom
This paper describes the mathematics classroom from the perspective of social phenomenology. Here the classroom is seen as an environment of signs, comprising things and people, which impinge on the reality of the individual child. The paper introduces a framework through which mathematical work is seen as taking place in the imagined world through the filter of the world in immediate perception. This provides an approach to structuring evolving mathematical understanding. It is suggested that mathematical ideas are contained and shaped by the child's personal phenomenology, which evolves through time. Further, I argue these ideas are never encountered directly but rather are met through a circular hermeneutic process of reconciling expectation with experience. © 1996 Kluwer Academic Publishers
Schwer einzuordnen
Mummendey HD. Schwer einzuordnen. In: Bauersfeld H, ed. Bildung und Aufklärung: Studien zur Rationalität des Lehrens und Lernens ; Festschrift für Helmut Skowronek zum 60. Geburtstag. Münster [u.a.]: Waxmann; 1993: 123-125
Schwer einzuordnen
Mummendey HD. Schwer einzuordnen. In: Bauersfeld H, ed. Bildung und Aufklärung: Studien zur Rationalität des Lehrens und Lernens ; Festschrift für Helmut Skowronek zum 60. Geburtstag. Münster [u.a.]: Waxmann; 1993: 123-125
Sudden cardiac death: clinical evaluation of paediatric family members
Aims To evaluate paediatric relatives of first- and non-first-degree family victims with a history of premature sudden cardiac death (SCD) or aborted cardiac arrest (ACA). Methods and results Thirty-six consecutive referred families after SCD (n = 29) or ACA (n = 7) of a family member were analysed. Referral was either due to an inherited heart disease identified after autopsy, post-event, or family evaluation (n = 20 families) or due to sudden unexplained death (SUD, n = 16 families). In 3 of 16 (19%) SUD families, an inherited heart disease was diagnosed by evaluation of the paediatric relatives. In 5 of 25 (20%) referred paediatric relatives of SUD families, an inherited heart disease was identified, mainly sinus node dysfunction (n = 3). A total of 13 of 33 (39%) referred paediatric relatives of families with known inherited heart disease were affected, mainly with cardiomyopathy (n = 5) and primary electrical disease (n = 7). Prevention of SCD was initiated in 16 of the affected children by implantation of an antibradycardia device (n = 3), an implantable cardioverter defibrillator (ICD, n = 6), and/or antiarrhythmic medication (n = 8). Appropriate and successful ICD discharges occurred in four. Conclusion A stepwise, comprehensive clinical investigation of SCD or ACA families identifies a substantial number of paediatric relatives at risk of SCD. This allows for targeted prevention by effective treatments and evaluation of further relatives
Determination of Catecholamines in Plasma by HPLC and Amperometric Detection. Comparison with a Radioenzymatic Method
Peer Reviewe
Myocarditis and coronary dilatation in the 1st week of life: neonatal incomplete Kawasaki disease?
Acute heart failure in the early neonatal period is rare. Normally it is due to asphyxia, severe septicaemia, a congenital heart malformation or a viral myocarditis. Kawasaki disease (KD) as a cause of an neonatal myocarditis is not an established diagnosis. KD is a vasculitis of still unknown origin occurring predominantly in infants and preschool children. KD before the age of 3 months is rare. There are only few reports about KD in the 1st month. We present a newborn who showed the cardiac symptoms of KD in the 1st week of life with coronary dilatation and myocarditis. CONCLUSION: The diagnosis of incomplete KD should be considered not only in infants but also in newborns with signs of myocarditis and coronary abnormalities. Therapy with gammaglobulins may prevent the sequelae of coronary involvement
Angiotensin-converting enzyme inhibitors in pediatric patients with mitral valve regurgitation-case-control study and review of the literature
OBJECTIVES: To investigate the effectiveness of chronic administration of angiotensin-converting enzyme inhibitors in pediatric patients with mitral valve regurgitation. DESIGN, SETTING, PATIENTS, INTERVENTIONS: This was a case-control study of all echocardiograms of patients with moderate-to-severe mitral valve regurgitation, who underwent chronic administration of angiotensin-converting enzyme inhibitors between January 1990 and December 2006 at a single center.
OUTCOME MEASURES: Echocardiographic parameters (left ventricular end-diastolic diameter, left ventricular posterior wall diameter, interventricular septum diameter, left atrium to aortic root diameter ratio, grade of mitral valve regurgitation, shortening fraction) were analyzed before and during therapy with angiotensin-converting enzyme inhibitors in 12 patients and compared with 12 patients without medications after one month and one year.
RESULTS: Twenty-four consecutive pediatric patients (median age of 7 years with a range 1 month-16 years) with moderate-to-severe mitral valve regurgitation were included. Data are given as standard deviation scores (z-scores) derived from body-surface-adjusted normal values. During angiotensin-converting enzyme inhibition left ventricular end-diastolic diameter decreased from mean z-score 2.04 to 1.66 (after 1 month) and to 1.73 (after 1 year), while left ventricular posterior wall diameter decreased from 0.25 to 0.12 (after 1 year), respectively. Shortening fraction, interventricular septum diameter, grade of mitral valve regurgitation, and left atrium to aortic root diameter ratio remained stable.
CONCLUSIONS: In this case-control study of patients with moderate-to-severe mitral valve regurgitation effectiveness of angiotensin-converting enzyme inhibition on left ventricular dimensions and function after 1 month and 1 year is limited. Reviewing the literature, the lack of long-term follow-up studies with large patient cohorts and controversial study-results in adults require a prospective long-term multicenter follow-up study in pediatric patients
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