Atrial Arrhythmias in Long-QT Syndrome under Daily Life Conditions: A Nested Case Control Study

Background: The long-QT syndromes (LQTS) are inherited electrical cardiomyopathies characterized by prolonged ventricular repolarization and ventricular arrhythmias. Several genetic reports have associated defects in LQTS-causing genes with atrial fibrillation (AF). We therefore studied whether atrial arrhythmias occur in patients with LQTS under daily-life conditions.
Methods: We systematically assessed atrial arrhythmias in LQTS patients and matched controls using implanted defibrillators or pacemakers as monitors of atrial rhythm in a nested case-control study. Twenty-one LQTS patients (3 male; 39 ± 18 years old; 18 on β blocker, ICD therapy duration 6.3 ± 2.7 years; 4 LQT1, 6 LQT2, 2 LQT3) were matched to 21 control subjects (13 male; 50 ± 19 years old; 3 on β blocker; pacemaker therapy duration 8.5 ± 5.5 years; 19 higher-degree AV block, 2 others). LQTS patients were identified by a systematic search of the LQTS patient databases in Münster and Munich.
Results: One-third (7 of 21) of the LQTS patients developed self-terminating atrial arrhythmias (atrial cycle lengths <250 ms). Only one control patient developed a single episode of postoperative AF (P < 0.05 vs LQTS).
Conclusions: LQTS patients at high risk for ventricular arrhythmias may develop short-lasting atrial arrhythmias under daily-life conditions, suggesting that prolonged atrial repolarization may contribute to the initiation of AF.     

The use of open MRI in otorhinolaryngology: initial experience.

Intraoperative imaging in head and neck surgery is a useful tool in many situations. In addition to being helpful for intraoperative orientation, real-time imaging enables visualization of the progress of surgery and the completeness of tumor resection. Regions in the head and neck to which access is difficult, and which therefore have a high incidence of morbidity and risk for the patient, can be approached more easily and safely in an open MRI than in a conventional way. Interventions in the open MRI (Signa SP, 0.5 Tesla) were performed with nonmagnetic instruments and an MR-safe microscope. For intraoperative navigation, the integrated FlashPoint system is helpful, because it allows targeting of the tumor by a calculated virtual line. T1W spin-echo, T2W fast spin-echo, and 3D T1W gradient-echo sequences were used for high-resolution imaging. Real-time imaging is achieved by fast multiplanar spoiled gradient-echo sequences or T2 single-shot fast spin-echo sequences. From 1996 to the present, we biopsied 17 petroclival tumors, performed paranasal sinus surgery in five cases, biopsied two neck masses, and inserted tubes for brachytherapy in 12 cases. No complications were observed. In all surgical procedures, a good resolution was obtained with MRI, especially for soft-tissue structures. The tumor could be targeted exactly, and all specimens revealed the relevant histology. In paranasal sinus surgery, however, the success rate was lower because it was difficult to distinguish blood from pathologic tissue. The insertion of tubes for brachytherapy was successful in all cases. It was possible to apply the tubes parallel to each other, 1 cm apart. Relevant biopsies could be taken of both neck masses. The indications for the use of open MRI in otorhinolaryngology are biopsies of tumors in regions that are difficult to approach, such as the petrous apex and petroclival region, the parapharyngeal space, and the orbit. Furthermore, the open MRI can be useful in paranasal sinus surgery, in the evaluation of tissue resection, and in the detection of the anatomy of delicate structures such as the internal carotid artery, the skull base, and the orbit. In addition, active navigation in the open MRI is possible with the integrated FlashPoint system. The advantage over conventional navigation systems lies in the possibility of real-time imaging, which allows detection of tissue changes occurring during the procedure.     

Hemorheologic, micro- and macrocirculatory effects of hypervolemic infusions of middle molecular weight hydroxyethyl starch (10%, 200,000/0.62) in healthy probands

During an open clinical trial the influence of hypervolemic hemodilution (Infusion of 500 cc Eloh?st within 1 h) on macrocirculation, microcirculation and blood fluidity of healthy volunteers was investigated. Blood pressure and heart rate remained constant during the infusion period and later on. The decline in hematocrit after 6 h was four points, plasma viscosity and erythrocyte aggregation, however, increased significantly. Three hours after completion of the infusion a significantly elevated blood flow in the common carotid artery could be assessed with a return to approximately normal values after 6 h. The improvement of the microcirculatory flow took a longer period of time. After 6 h a significantly increased erythrocyte velocity in the nailfold capillaries along with a significant augmentation of transcutaneously measured partial oxygen pressure could be stated.     

Easy improvement of signal-to-noise in RARE-sequences with low refocusing flip angles. Rapid acquisition with relaxation enhancement.

It is demonstrated that the signal intensity in a RARE (TSE, FS...)-sequence with low refocusing flip angle alpha can be significantly increased by setting the flip angle of the first refocusing pulse to 90 degrees +alpha/2. In addition to the gain in signal intensity, the initial signal modulations over the first few echoes are reduced compared to a CPMG-echo train with constant alpha.     

Interaction of Viagra with the NO donors molsidomine and RE 2047 with regard to antithrombotic and blood pressure lowering activities.

After p.o. administration to rats in doses up to 30 mg/kg, Viagra showed no antithrombotic effect. However, it enhanced the inhibition of thrombus formation by RE 2047 from 9% to 17% (5 + 5 mg/kg) or 19% to 27% (10 + 10 mg/kg) in arterioles. This effect was even more obvious in venules where an inhibition of 9% (5 + 5 mg/kg) or 15% (10 + 10 mg/kg) was seen whereas the individual drugs had no effect. The antithrombotic activity of molsidomine was not altered. The blood pressure (b.p.) of spontaneously hypertensive rats was reduced by the combination of Viagra and RE 2047 (5 + 5 mg/kg) to 94% of normal after 2 h while the individual drugs had no effect at this dose. The coadminstration of 10 mg/kg of each drug reduced the b.p. to 87% of normal. The combination of Viagra with molsidomine decreased b.p. to 84% (5 + 5 mg/kg) or 79% (10 + 10 mg/kg), respectively.     

Aktuelle Aspekte in der Verankerung von Hamstringsehnen-Transplantaten in der Kreuzbandchirurgie

Zusammenfassung. Die Verwendung von Hamstringsehnen-Transplantaten in der Kreuzbandchirurgie hat in den letzten Jahren wieder zunehmend an Bedeutung gewonnen. Der wesentliche Vorteil der Hamstringsehnen gegenüber dem mittleren Patellarsehnendrittel liegt in einer erheblich reduzierten Transplantatentnahmemorbidit?t, kombiniert mit einer sehr hohen Zugfestigkeit. Die oss?re Transplantatintegration unterliegt jedoch spezifischen biomechanischen und biologischen Rahmenbedingungen. Neue Entwicklungen auf dem Gebiet der Transplantatverankerung haben sich darauf konzentriert die initiale Verankerungsfestigkeit zu erh?hen und das Verankerungslevel weiter in Richtung Gelenkspalt zu verschieben. Es wird also eine anatomische Verankerung, m?glichst nahe dem original Kreuzbandansatz angestrebt. Ziel der vorliegenden übersichtsarbeit ist es neue Entwicklungen unter besonderer Berücksichtigung von biomechanischen und biologischen Faktoren vorzustellen und zu diskutieren. Spezielles Augenmerk liegt hier auf der Interferenzschrauben-Verankerung von Weichgewebe-Transplantaten, femoralen Transfixationsystemen und dem sog. Konzept der Hybridfixation.