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Objectives: Implantation of an additional HV-P/S lead versus extraction of the defective HV-P/S lead and implantation of a new one is one possible therapeutic approach in cases of a defective high-voltage pace/sense lead (HV-P/S). No information is available on potential differences in clinical outcome in these different approaches. Methods: Between January 2000 and February 2006, 86 patients with HV-P/S lead defect received either an additional transvenous HV-P/S lead (n = 33, group 1) or the HV-P/S lead was replaced (n = 53, group 2). The duration of the initially implanted leads was significantly different in the two groups (7.4 ± 2.9; group 1 and 4.1 ± 3.4 years; group 2).The outcome of these two groups of patients was retrospectively analyzed. Results: Seventy-three patients [85%] survived until the end of follow-up of 29 ± 15 (group 1) and 33 ± 21 (group 2) months (P = ns), respectively. Thirteen patients died: six in group 1 and seven in group 2 (P = ns). Fourteen patients experienced perioperative complications (group 1: six; group 2: eight; P = ns). ICD system-related complications occurred in 22 patients (group 1: seven; group two: 15; P = ns). The event-free cumulative survival of patients with additional and replaced HV-P/S lead for postoperative events (including death) after 1, 2, and 3 years was 82%, 70%, 70%, and 86%, 81%, 66%, respectively (P = 0.93). Conclusions: Implantation of an additional HV-P/S lead or replacement of the HV-P/S lead in case of HV-P/S lead failure is statistically not different concerning mortality and morbidity. There are no predictors for further lead defects. Implantation of an additional HV-P/S lead should not be recommended in young patients or patients with greater likelihood of living many years. Predictors for death were an age over 70 years and renal insufficiency.

A prototype composed of four resistive plate chamber layers has been exposed to quasi-monoenergetic protons produced from a deuteron beam of varying energy (200 to 800 AMeV) in experiment S406 at GSI, Darmstadt, Germany. The aim of the experiment is to characterize the response of the prototype to protons in this energy range, which deposit from 1.75 to 6 times more energy than minimum ionizing particles. Each layer, with an active area of about 2000 × 500 mm2, is made of modules containing the active gaps, all in multigap construction. Each gap is defined by 0.3 mm nylon mono-filaments positioned between 2.85 mm thick float glass electrodes. The modules are operated in avalanche mode with a non-flammable gas mixture composed of 90% C2H2F4 and 10% SF6. The signals are readout by a pick-up electrode formed by 15 copper strips (per layer), spaced at a pitch of 30 mm, connected at both sides to timing front end electronics. Results show an uniform efficiency close to 100% along with a timing resolution of around 60 ps on the entire 2000 × 500 mm2 area.

By molecular beam epitaxy, a thin (≈200 nm) ZnSe film was grown on a p -type Si substrate covered with an InSe buffer layer. The InSe buffer is used to bypass the huge lattice mismatch of 4.4% between ZnSe and Si in order to ensure the growth of a stress-free optically smooth ZnSe film. Reflection, photoluminescence and photocurrent properties at 300 K demonstrated that the thin ZnSe film grown represents a high quality etalon with the bandgap of cubic bulk ZnSe. Furthermore, it is shown that the ZnSe/InSe/Si heterojunction exhibits rectification and a nearly constant intrinsic photoconductivity between 500 and 900 nm. This appreciable behavior makes the ZnSe/InSe/Si heterojunction very attractive for applications to sophisticated light detectors.

Pediatric long-term ventricular support with paracorporeal assist devices is performed in only a few institutions. We report on our experience with two pediatric paracorporeal devices, which have been implanted in neonates, infants, and small children. Seven children with ages ranging from 2 weeks to 6 years and a body weight of 3 to 19 kg were provided with either a Medos or a BerlinHeart System. The underlying heart diseases included dilative cardiomyopathy (n = 3), endocardial fibroelastosis (n = 2), Ebstein anomaly, and status post redo aortic valve replacement (n = 1). All children were in New York Heart Association class IV and were inotrope dependent. Three children were provided with a Medos system and 4 children with a BerlinHeart Excor device. In 6 cases, left ventricular support, and in 1 case, right ventricular support was performed. All patients were stabilized with univentricular mechanical support. The perioperative course was uneventful, and end-organ function was well recovered. Reexploration for bleeding and evacuation of mediastinal blood clots was necessary in all three neonates but not in any of the older infants. Severe thromboembolic events were only noticed in the neonates. Successful bridge to transplantation was performed in 6 of the 7 patients (87.5%). Our late results have been quite encouraging, as they readily prove that pediatric long-term mechanical support is possible with a high quality of life and an acceptable low complication rate.

Background To remove failing or infected implantable cardioverter defibrillator leads, percutaneous techniques and open heart surgery are two common approaches. However, well-defined indications for either technique are not available. We summarize our experience with implantable cardioverter defibrillator system explantation using open heart surgery and percutaneous lead removal. Methods A total of 1,391 transvenously introduced implantable cardioverter defibrillator systems were implanted during the analyzed time interval from January 1995 to June 2005 in our institution. In 21 patients (1.5%), open heart surgery for implantable cardioverter defibrillator lead and generator explantation was applied (group A), and in 53 patients (3.8%), a percutaneous lead removal was possible (group B). The log-rank test was used to calculate differences in survival between both patient groups, and the Student's t test was applied for differences in nonlethal complications. Results The 30-day, 6-month, 12-month, and 5-year survival rates were 91%, 91%, 81%, and 71%, respectively, for group A patients, and 100%, 100%, 94%, and 78%, respectively, for group B patients, which was not statistically different ( p = 0.11). After open heart surgery, survival was comparable for cases with lead removal because of lead infection and those with lead malfunction ( p = 0.28); however, patients with open heart surgery had a longer hospital stay ( p = 0.03). Student's t test revealed no statistical difference in nonlethal complications between both patient groups ( p = 0.37). Conclusions As open heart surgery yielded similar results with regard to survival and complications, implantable cardioverter defibrillator lead removal using extracorporeal circulation may be well justified as a last therapeutic option, eg, in case of large bacterial vegetations.

The inherent functionality of a printed wiring board (PWB) can be dramatically increased by embedding electronic components into the board. For resistors, capacitors and inductors, technological turnkey solutions are offered by major manufacturers and novel technologies are also under development. A further boost of functionality will be accomplished by the integration of active chips into the board. Two approaches for chip integration into the board will be discussed in detail: the chip in polymer (CIP) approach and the embedding of chips into flexible PWBs via flip chip process.

The interface formation between vacuum evaporated CdS and ultrahigh vacuum-cleaved CuInS2 single crystals has been studied by synchrotron excited photoelectron spectroscopy. The valence band discontinuity is determined directly from valence band difference spectra to be ΔEV=0.6 (±0.1) eV. This value is significantly smaller than for other preparation conditions given in the literature and evidently not suitable for solar cell applications. The similarity to observations at the CdS/CuInSe2 interfaces suggests that neutrality levels play a dominant role in establishing the band lineup at interfaces containing chalcopyrite semiconductors.

dioverter/Defibrillator Who Receive Additional Transvenous Pace/Sense Leads. Background: Implantation of an additional pace/sense (P/S) lead is commonly used in patients with implantable cardioverter/defibrillators (ICDs)to overcome P/S defects of integrated defibrillation leads (HV-P/S leads). No information is available about the clinical outcome and the incidence of complications in these patients. Methods: Retrospective analysis was performed in 151 patients (125 male, age 54.9 ′ 13.6 years, LVEF 48.1 ′ 17.8%, CAD in 86 [57%], DCM in 24 [16%], ARVCM in 11 [7%]) who received an additional P/S lead between 1990 and 2002 (54 patients with abdominal and 97 patients with pectoral ICD system). Statistical analysis was done using Kaplan-Meier survival curves. Results: The average follow-up (FU) after implantation of the additional P/S lead was 43 ′ 27 months. In total 117 patients [77.5%] remain implanted; 22 patients died due to cardiac-related reasons. After a FU of 23 ′ 23 months, 43 patients [28.5%] experienced lead-related problems after implantation of the additional P/S lead: oversensing in 23 [53.5%], insulation defect in 3 [7.0%], fracture in 1 [2.3%], system infection in 4 [9.3%], and defect of the HV-P/S lead in 6 [14.0%] patients. The event-free cumulative survival of the additional P/S lead after 1, 2, and 5 years was 87.0%, 79.8%, and 59.4%, respectively (for pectoral leads: 89.6%, 82.0%, and 60.0%, respectively). Conclusions: Implantation of an additional P/S lead in case of failure ofan HV-P/S lead is safe. However, it is associated with a substantial rate of complications during FU. Therefore, extraction of damaged defibrillation leads instead of implantation of P/S leads should be favored.

Background Tumours of the heart are rare. Different histological subtypes are known. The most common tumour entity is benign cardiac myxoma. Malignant heart tumours are less common. Tumours originating in other organs such as the kidney may also affect the heart by tumour progression via the inferior caval vein. A large experience with surgical treatment of different types of heart tumours is presented. Methods Between January 1989 and April 2004, 108 patients with a heart tumour were included in a database. All patients underwent radical surgical resection, except for 2 patients who had malignant lymphoma of the heart. Results Histological findings included 78 myxomas (72.2 %), and 6 other benign cardiac tumours in 5.6 % of the patients. Primary malignant heart tumours were seen in 10 (9.2 %) and renal cell carcinoma with cardiac involvement in 6 (5.6 %) patients. Eight patients presented with tumour metastases inside the heart (7.4 %). Mean overall survival was 12.7 years for myxoma patients and 5.6 years for patients with other benign heart tumours. Patients with primary malignant heart tumours survived 5.5 years on average. Conclusions Heart tumours are rare, but usually life-threatening. Radical surgical resection is the therapy of choice and may offer excellent long-term survival, even in cases with malignant heart tumours.

Von der Europäischen Union werden derzeit zwei Projekte zur Weiterentwicklung von Leiterplattentechnologien gefördert. In beiden Projekten geht es um die Einbettung elektronischer Komponenten in die Leiterplatte. Im Projekt HIDING DIES werden aktive Chips in die Aufbaulagen starrer Leiterplatten integriert. In SHIFT wird eine weiter gefasste Technologieplattform für die flexible Leiterplatte entwickelt, wo neben verschiedenen Aufbautechnologien, -Prozessen und -Varianten ist die Einbettung von passiven und aktiven Komponenten in die flexible Leiterplatte der Schwerpunkt der Technologieentwicklung ist. Ziel beider Projekte ist es, eine mittelfristige Umsetzung dieser Technologien in der Produktion zu ermöglichen, wobei die dazu erforderlichen Investitionen für den Leiterplattenhersteller gering sein sollen.

Implantation of a transvenous device in patients with a tricuspid valve replacement or a complex congenital heart disease with no access to the right ventricle represents problems. The lack of access to the right ventricle might preclude transvenous placement of a defibrillation lead at ICD implantation. A young patient (21 years) with a history of severe chest trauma with rupture of the tricuspid valve as well as the right coronary artery and consecutive inferior myocardial infarction was initially treated with tricuspid valve replacement (St Jude Medical artificial prosthesis, 33 mm) and a bypass graft to the right coronary artery. Four years later, the patient was admitted with a hemodynamically not tolerated ventricular tachycardia (VT: CL 250 ms, LBBB, left axis). The VT could be reproduced during electrophysiological testing. An ICD was implanted subpectorally in combination with a transvenous active fixation ICD lead. The transvenous ICD lead was placed via a guiding catheter into a coronary sinus branch (middle cardiac vein). Acceptable pacing and sensing values could be obtained. The defibrillation threshold was 25 J. In conclusion transvenous ICD lead implantation into a side branch of the coronary sinus in combination with a pectorally implanted "active can" ICD device seems to be an alternative approach. This approach may avoid implantation of additional subcutaneous defibrillation leads or even thoracotomy for ICD implantation.

Bei 5–10% der Patienten mit Nierentumoren wird eine Beteiligung im Sinne einer Infiltration oder eines intraluminalen Tumorwachstums in der Vena cava inferior (VCI) und/oder des rechten Vorhofes beobachtet. Wenn der Nierentumor einen sogenannten Cavazapfen gebildet hat, nimmt die Hohe der cavoatrialen Ausbreitung keinen Einfluss auf das Uberleben. Die radikale Entfernung des Tumors mitsamt Tumorzapfen stellt heute bei Patienten ohne lokale Lymphknotenmetastasen und ohne Fernmetastasen die Primartherapie der Wahl dar. Wir berichten uber den Verlauf und die Therapie von 17 Patienten mit einem Nieren-Zell-Karzinom und cavoatrialer Tumorbeteiligung sowie uber 6 weitere Patienten mit anderen Tumorarten. Trotz aufwandiger Operation mit Herz-Lungenmaschine, tiefer Hypothermie und Kreislaufstillstand kommt es im Vergleich zur Tumornephrektomie ohne Beteiligung der Vena cava zu einer vertretbaren Erhohung der perioperativen Morbiditat und Letalitat. Ein Langzeituberleben ist trotz fortgeschrittenem Tumorstadium mit cavoatrialer Ausdehnung nach radikaler Resektion moglich.

Background: B-type natriuretic peptide (BNP) is released from the cardiac ventricles in response to increased wall tension. We studied the relation of NT-proBNP to Heart Failure Survival Score (HFSS) and New York Heart Association (NYHA) class in patients with chronic heart failure (CHF). We also studied the impact for recipient selection for cardiac transplant and assessed it as a predictive and prognostic marker of CHF. Methods: A total of 550 patients with dilative cardiomyopathy (n 323), and coronary artery disease (n 227) were prospectively examined. All patients underwent spiroergometry, echocardiography, right heart catheterization, and electrocardiogram. Routine blood levels and NT-proBNP were measured. The clinical selection for cardiac transplant candidates was adjudicated by 2 independent cardiologists who were blinded to the results of NT-proBNP assays. Clinical outcome and predictive power of NT-proBNP were analyzed. Results: NT-proBNP levels in patients clinically considered for cardiac transplantation were significantly higher (2293 ng/ml vs 493 ng/ml; p 0.001). The receiver operating characteristic (ROC) analysis regarding transplant candidacy showed an area under the ROC curve (AUC) of 0.84 0.01 for HFSS, 0.86 0.001 for NYHA, and 0.96 0.01 for NT-proBNP. Patients with increasing NT-proBNP levels or remaining elevated levels despite adequate heart insufficiency treatment were maintained with left ventricular assist device implantation (n 10) or urgent heart transplantation (n 2). Patients with NT-proBNP levels above 5000 pg/ml had a mortality rate of 28.4% per year. Twenty-eight patients died during the observation period; all these patients were within NYHA Classes 3 and 4 (NT-proBNP 5423 423 ng/ml). Conclusions: NT-proBNP discriminates patients at high likelihood of being a candidate for transplantation and provides prognostic informations in patients with CHF. NT-proBNP levels above 5000 pg/ml at admission were associated with death, and these levels markedly discriminated candidates for left ventricular assist devices or urgent transplantation. J Heart Lung Transplant.

Epitaxial films of Wurtzite CdS in (0001) orientation have been grown on MoTe2 (0001) substrates in spite of a lattice mismatch of 15%. The film growth was in situ monitored by soft x‐ray photoelectron spectroscopy and low energy electron diffraction. The interface is found to be nonreactive and atomically abrupt. The CdS overlayer tends to grow in three‐dimensional clusters (Volmer–Weber growth mode).

We report on our recent nuclear resonance fluorescence experiments on l52,l54,l56Gd. Decay branches of the scissors mode to intrinsic excitations are observed. They are interpreted as a new signature for a spherical-to-deformed nuclear shape phase transition.

The electric dipole strength distribution in 130Te has been investigated using the method of Nuclear Resonance Fluorescence. The experiments were performed at the Darmstadt High Intensity Photon Setup using bremsstrahlung as photon source and at the High Intensity γ→$\overrightarrow \gamma $-Ray Source, where quasi-monochromatic and polarized photon beams are provided. Average decay properties of 130Te below the neutron separation energy are determined. Comparing the experimental data to the predictions of the statistical model indicate, that nuclear structure effects play an important role even at sufficiently high excitation energies. Preliminary results will be presented.

Epitaxial lattice mismatched heterointerfaces between layered semiconductors and themselves and II-VI semiconductors (CdS, CdTe), respectively, have been prepared and their band lineup determined by photoemission. Different physical mechanisms, which govern the heterointerface formation, can be discriminated due to the specific properties of the van der Waals (vdW) surface. The interfaces between layered semiconductors mostly follow the electron affinity rule with a small but systematic deviation, which is assigned to the influence of interfacial quantum dipoles. However, the band lineup to the II-VI semiconductors shows a large interface dipole, which is related to a structural dipole from the polar, Cd terminated, face of the (111)- in case of Zinkblende CdTe- and the (0001)- in case of Wurtzite CdS- oriented overlayer film.