Insight into the Temperature-Dependent Canting of 4f Magnetic Moments from 4f Photoemission.

The orientation of the 4f moments offers an additional degree of freedom for engineering the spin-related properties in spintronic nanostructures of lanthanides. Yet, precise monitoring of the direction of magnetic moments remains a challenge. Here, on the example of the antiferromagnets HoRh2Si2 and DyRh2Si2, we investigate the temperature-dependent canting of the 4f moments near the surface. We demonstrate that this canting can be understood in the framework of crystal electric field theory and the exchange magnetic interaction. Using photoelectron spectroscopy, we disclose subtle but certain temperature-dependent changes in the line shape of the 4f multiplet. These changes are directly linked to the canting of the 4f moments, which is different for the individual lanthanide layers near the surface. Our results illustrate the opportunity to monitor the orientation of the 4f-moments with high precision, which is essential for development of novel lanthanide-based nanostructures, interfaces, supramolecular complexes, and single-molecule magnets for various applications.

Refraining from interaction can decrease fear of physical closeness during COVID-19.

Perception of peripersonal space (PPS) and interpersonal distance (IPD) has been shown to be modified by external factors such as perceived danger, the use of tools, and social factors. Especially in times of social distancing in the context of the COVID-19 pandemic, it is vital to study factors that modify PPS and IPD. The present work addresses the question of whether wearing a face mask as a protection tool and social interaction impact the perception of IPD. We tested estimated IPD in pictures at three distances: 50 cm, 90 cm, and 150 cm in both social interaction (shaking hands) and without interaction and when the two people in the pictures wore a face mask or not. Data from 60 subjects were analyzed in a linear mixed model (on both difference in distance estimation to the depicted distance and in absolute distance estimation) and in a 3 (distance: 50, 90, 150) × 2 (interaction: no interaction, shake hands), × 2 face mask (no mask, mask) rmANOVA on distance estimation difference. All analyses showed that at a distance of 50 and 90 cm, participants generally underestimated the IPD while at an IPD of 150 cm, participants overestimated the distance. This could be grounded in perceived danger and avoidance behavior at closer distances, while the wider distance between persons was not perceived as dangerous. Our findings at an IPD of 90 cm show that social interaction has the largest effect at the border of our PPS, while the face mask did not affect social interaction at either distance. In addition, the ANOVA results indicate that when no social interaction was displayed, participants felt less unsafe when depicted persons wore a face mask at distances of 90 and 150 cm. This shows that participants are on the one hand aware of the given safety measures and internalized them; on the other hand, that refraining from physical social interaction helps to get close to other persons.

During the COVID-19 pandemic participants prefer settings with a face mask, no interaction and at a closer distance.

Peripersonal space is the space surrounding our body, where multisensory integration of stimuli and action execution take place. The size of peripersonal space is flexible and subject to change by various personal and situational factors. The dynamic representation of our peripersonal space modulates our spatial behaviors towards other individuals. During the COVID-19 pandemic, this spatial behavior was modified by two further factors: social distancing and wearing a face mask. Evidence from offline and online studies on the impact of a face mask on pro-social behavior is mixed. In an attempt to clarify the role of face masks as pro-social or anti-social signals, 235 observers participated in the present online study. They watched pictures of two models standing at three different distances from each other (50, 90 and 150 cm), who were either wearing a face mask or not and were either interacting by initiating a hand shake or just standing still. The observers' task was to classify the model by gender. Our results show that observers react fastest, and therefore show least avoidance, for the shortest distances (50 and 90 cm) but only when models wear a face mask and do not interact. Thus, our results document both pro- and anti-social consequences of face masks as a result of the complex interplay between social distancing and interactive behavior. Practical implications of these findings are discussed.

Efficacy and safety of insulin detemir versus glargine in patients with diabetes: a systematic review and meta-analysis.

OBJECTIVES: Performing an updated meta-analysis to compare the safety and efficacy of insulin glargine and insulin detemir in adults with type 1 and type 2 diabetes. METHODS: Electronic databases were searched up to 18 August 2021. A random-effects model was applied to pool data from included studies to calculate the standardized mean differences (SMDs) for the continuous variables and relative risks (RRs) for the dichotomous variable. RESULTS: Nine studies compared insulin detemir and insulin glargine in type 2 diabetes and three studies in patients with type 1 diabetes. The pooled SMD of weight gain was -0.59 (95% CI -1.05 to -0.14; P=0.01; I2=98%) in patients with type 2 diabetes. The pooled RR of severe hypoglycemia was 0.28 (95% CI 0.12 to 0.63; P=0.002; I2=0%) in patients with type 1 diabetes. The effects of detemir and glargine on HbA1c, fasting plasma glucose, nocturnal hypoglycemia, and overall hypoglycemia were not statistically different (P>0.05). CONCLUSIONS: It was found that there is no clinically considerable difference between the impacts of insulin detemir and insulin glargine in diabetic patients. The only statistically significant differences were less weight gain in type 2 diabetes and fewer episodes of severe hypoglycemia in type 1 diabetes with insulin detemir.

[Postoperative leaks in the gastrointestinal tract-diagnosis and treatment]. / Postoperative Leckagen im Gastrointestinaltrakt ­ Diagnostik und Therapie.

Postoperative leaks following esophageal, gastric, colonic or rectal resection represent a life-threatening complication that is associated with high morbidity and mortality. Leaks are generally diagnosed with a combination of the following: recognition of clinical deterioration, laboratory results, endoscopic and radiological imaging. In case of intraperitoneal leaks, surgery is mandatory. In case of mediastinal or retroperitoneal anastomotic insufficiencies, treatment mainly comprises interventional endoscopic procedures in an interdisciplinary approach. For endoscopic therapy, there are mainly two different methods described: closure of the defect with fully covered self-expandable stents with external drainage and closure of the defect with simultaneously internal drainage by endoscopic vacuum therapy.

New risk and protective factors for severe hypoglycaemia in people with type 1 diabetes.

AIMS: To evaluate risk factors for severe hypoglycaemia (SH) in patients with type 1 diabetes (T1DM). METHODS AND RESULTS: Retrospective observational and comparative study. All SH occurring between 2007 and 2014 in a German population (Lippe-Detmold) were captured. Characteristics of patients with T1DM and SH were compared with a control group being equivalent concerning age, diabetes duration, HbA1c, comorbidity, and ß-blocker treatment. SH was defined as a symptomatic event requiring treatment with intravenous glucose or glucagon administration and being confirmed by a blood glucose measurement of <2.8 mmol/l. Predictive factors for SH were analysed by a multivariable regression model. As many as 405 cases of SH in T1DM occurred in 206 subjects; 50% of episodes were related to 31 patients who experienced ≥3 SH. Need for nursing care (OR 4.88), treatment with NPH (OR 3.68), and impaired hypoglycaemia awareness (OR 2.06) were the strongest risk factors for SH (all p < 0.05, all pFDR-adjusted < 0.10; false discovery rate (FDR)). Depression (OR 0.14), treatment with CSII (OR 0.39) and short-acting insulin analogues (OR 0.31) appeared to be protective (all p < 0.10; FDR-adjusted). The probability of SH onset was significantly higher in patients who had previously experienced recurrent SH episodes. ß-Blocker treatment did not appear to be a risk factor. CONCLUSION: The complex risk for SH in people with T1DM can be reduced by treatment with CSII and short-acting analogues. Future structures of diabetes care will be challenged by the need of treating increasingly geriatric subjects with T1DM having a high risk of SH.

[Influence of ECMO and IABP on coronary blood flow. Valuable combination or waste of resources?]. / Einfluss von ECMO und IABP auf die Koronardurchblutung. Sinnvolle Kombination oder Ressourcenverschwendung?

BACKGROUND: The treatment of patients in severe cardiogenic shock with an intra-aortic balloon pump (IABP) or extracorporeal membrane oxygenation (ECMO) is a common procedure to achieve stabilization. Only limited data are available on the simultaneous use of both systems. The aim of the present study was to assess the effect of the concomitant use of IABP and ECMO on coronary blood flow. In addition, the influence of antegrade and retrograde perfusion was evaluated. METHODS: A median sternotomy was performed in adult pigs under general anesthesia. Arterial ECMO perfusion was realized through the ascending aorta or the femoral artery, and the IABP was implanted via the second femoral artery. Six measurements of arterial pressure in the left anterior descending artery (LAD) and in the left atrium were made at intervals of 2 min. In addition, lactate concentration and oxygen saturation in the coronary sinus were recorded. The ECMO support was either 100 or 50 % of cardiac output. Each experiment was carried out first without and then with additional IABP support. RESULTS: The simultaneous use of ECMO and IABP is feasible for antegrade perfusion, where the IABP leads to an increase of blood pressure in the coronary arteries. In addition, the myocardial oxygen supply improves. By contrast, the use of an IABP in retrograde perfusion leads to a reduction of blood pressure in the LAD and to a reduced oxygen supply. A comparison between antegrade and retrograde perfusion with IABP support showed significantly better mean arterial pressure in the LAD for antegrade perfusion. Without IABP, blood pressure in the LAD was better in retrograde perfusion. CONCLUSION: In antegrade perfusion the simultaneous use of IABP and ECMO is useful. In retrograde perfusion IABP impairs the mean arterial pressure and consequently the perfusion of the coronary arteries.

Prognostic significance and relationship of worst lead residual ST segment elevation with myocardial damage assessed by cardiovascular MRI in myocardial infarction.

OBJECTIVE: To investigate the relation of residual worst lead ST segment elevation (WL-STE) after ST segment myocardial infarction (STEMI) with infarct size and microvascular injury assessed by cardiovascular magnetic resonance (CMR) imaging. BACKGROUND: WL-STE in patients with acute reperfused STEMI has been shown to identify high risk patients for major adverse cardiovascular events (MACE). However, the relation of WL-STE with myocardial damage is unknown. METHODS: In this multicentre study we analysed ECG data 90 min after primary percutaneous coronary intervention (PCI) in 763 STEMI patients. WL-STE was defined as the absolute magnitude of STE in the most affected lead on the post-PCI ECG. Patients were categorised into three groups (<1 mm, 1-2 mm, and ≥2 mm). CMR was performed within 1 week after infarction for comprehensive assessment of myocardial damage using a standardised protocol. The primary clinical endpoint was MACE defined as death, reinfarction, and new congestive heart failure within 12 months after infarction. RESULTS: WL-STE <1 mm, 1-2 mm, and ≥2 mm was present in 155 (20%), 328 (43%), and 280 (37%) patients, respectively. Myocardial damage determined by CMR demonstrated a graded relationship of infarct size (median (IQR) 13.3 (6.2-20.3)%LV vs 13.7 (7.6-21.3)%LV vs 22.5 (15.6-31.2)%LV, p<0.001), the myocardial salvage index (60.8 (37.0-84.5) vs 55.0 (36.6-73.9) vs 42.7 (26.2-58.2), p<0.001), and microvascular obstruction (0.0 (0.0-0.9)%LV vs 0.0 (0-1.0)%LV vs 1.2 (0.0-3.6)%LV, p<0.001) across the three groups. WL-STE ≥2 mm was strongly associated with MACE 12 month after infarction (HR 1.93, 95% CI 1.11 to 3.37; p=0.02). CONCLUSIONS: This largest CMR study to date correlating post-PCI WL-STE with markers of myocardial damage demonstrates that WL-STE is significantly associated with infarct size, myocardial salvage, microvascular obstruction, and MACE in a high risk STEMI population. TRIAL REGISTRATION NUMBER: NCT00712101.

Response to cold acclimation in diapause pupae of Hyles euphorbiae (Lepidoptera: Sphingidae): candidate biomarker identification using proteomics.

The distribution range of Hyles euphorbiae covers distinct climates across the Palaearctic. Previous investigations showed a correlation between mitochondrial DNA identity of populations and climatic conditions related to winter; however, the lack of biomarkers hampers investigations to test whether geographically distinct populations do show specific molecular responses to low temperatures or whether they possess specific genetic identity at loci functionally related to cold response. The present study was designed to identify candidate protein biomarkers and biological processes that are associated with cold acclimation of overwintering H. euphorbiae diapause pupae. Specimens taken from a single central European population were gradually cooled from 20 °C to -2 °C over 36 days and 12 differentially abundant proteins were identified. In addition, DeepSuperSAGE sequencing technology was applied to study differentially regulated genes. There was incongruence between differentially abundant proteins and differentially expressed genes, but functional characteristics of regulated proteins and analyses of gene ontology term enrichment among differentially regulated genes pointed to activation of the same biological processes, e.g. oxidative stress response. As proteins represent biologically active molecules, candidate biomarkers derived from proteomics are considered well suited to explore intraspecific patterns of local adaptation to different climates.

Evaluating childhood obesity: magnetic resonance-based quantification of abdominal adipose tissue and liver fat in children.

PURPOSE: The purpose of this study is to establish and validate a magnetic resonance (MR)-based fat quantification package that provides an accurate assessment of abdominal adipose tissue and liver fat in children. MATERIALS AND METHODS: Ex vivo trials with a torso model and water-oil mixtures are conducted. Abdominal adipose tissue (AAT) is covered by magnetic resonance imaging (MRI) using a fat-selective sequence and is analyzed by a plug-in based on the open source software ImageJ. Liver fat (LF) is measured with localized 1H Magnetic Resonance Spectroscopy (1H MRS) and the jMRUI (java-based Magnetic Resonance User Interface) software package. Evaluation of the clinical methodology involved a study of 10 children in this feasibility study (mean age and body mass index: 13.3 yr; 33.3 kg/m²). To evaluate the method's validity, reference measurements were performed. RESULTS: Ex vivo trials with the torso model showed that adipose tissue was measured appropriately with a systematic underestimation by 9.3 ± 0.2 % (0.32 ± 0.064 kg). Coefficients of variation for both intra- and inter-observer measurements ranged between 0 - 2.7 % and repeated analyses showed significant equivalent results (p < 0.01). The lipid content obtained by 1H MRS ex vivo revealed significant equivalence with the predefined fat content in water-oil mixtures (p < 0.01). In vivo, the homemade plug-in significantly overestimated the AAT, with the visceral adipose tissue being most affected (+ 15.7 ± 8.4 %). CONCLUSION: Although an overestimation of the AAT by the presented plug-in should be taken into consideration, this children-friendly package enables the quantification of both LF and AAT within 30 min on a freeware-based platform.

[Effects of daily physical exercise at school on cardiovascular risk--results of a 2-year cluster-randomized study]. / Einfluss eines täglichen Schulsportunterrichts auf das kardiovaskuläre Risiko - 2-Jahres Ergebnisse einer Cluster-randomisierten Studie.

BACKGROUND AND OBJECTIVE: It was the aim of this study to measure the effects over two years of daily sport activity during the school-day on their physical fitness (primary endpoint), motor coordination and blood pressure (secondary endpoints). METHODS: A total of 232 children from eleven different 6 (th) grade classes were enrolled after informed parental consent. Their mean age was 11.1 ± 0.6 years. Six classes were randomly assigned for intervention (n=141), five as control (n=91). Those of the intervention cohort undertook, for five days weekly during the school year one hour of regulated sport exercise, including 15 min of endurance training. The pupils of the control group undertook customary sport activity (two hours a week). Anthropometric data were recorded and maximal oxygen uptake measured in each pupil, as well as blood pressure and motor coordination at the beginning and at the end of each of the two years of the study. The data were analyzed using the cluster randomization method. RESULTS: Maximal oxygen uptake (VO (2)max) had improved among the intervention group after two years, compared with the controls (3.12 m/kg/min, 95% confindence interval [CI] 0.06-6.19), while improvement in motor coordination just failed to reach statistical significance (3.06, 95% CI -0.17-6.29). There was no significant difference in systolic and diastolic blood pressure, but a downward trend in the prevalence of overweight and obesity from 12.1% to 7.8% in the intervention group. CONCLUSION: The results indicate that daily physical exercise during school hours should be given greater importance. But it will require a long-term trial to determine whether promotion of increased physical activity at school influences the prevalence of cardiovascular risk factors when the pupils reach adulthood.

Association of glucose metabolism with diastolic function along the diabetic continuum.

AIMS/HYPOTHESIS: Hyperglycaemia and insulin resistance have been linked to diastolic dysfunction experimentally. We investigated the association between glucose metabolism and diastolic function along the whole spectrum of glucose metabolism states. METHODS: In the observational Diagnostic Trial on Prevalence and Clinical Course of Diastolic Dysfunction and Diastolic Heart Failure (DIAST-CHF) study, patients with risk factors for heart failure were included. We analysed data including comprehensive echocardiography from a subgroup of patients classified by OGTT and history as normal (n = 343), prediabetic (n = 229) and non-insulin treated (n = 335) or insulin-treated (n = 178) type 2 diabetic. RESULTS: While ejection fraction did not differ, markers of diastolic function significantly worsened across groups. Prediabetes represented an intermediate between normal glucose metabolism and diabetes with regard to echocardiography changes. Prevalence and severity of diastolic dysfunction increased significantly (p < 0.001) along the diabetic continuum. Glucose metabolism status was significantly associated with prevalence of diastolic dysfunction on multivariate logistic regression analysis. In the whole cohort, HbA(1c) correlated with early diastolic mitral inflow velocity (E):early diastolic tissue Doppler velocity at mitral annulus (e') ratio (E:e') (r = 0.20, p < 0.001). HbA(1c) was significantly associated with E:e' on multivariate analysis. Similarly, glucose metabolism status was significantly associated with E:e' on multivariate analysis. The distance walked in 6 min decreased along the diabetic spectrum and was significantly correlated with E:e' and grade of diastolic dysfunction. CONCLUSIONS/INTERPRETATION: Glucose metabolism is associated with diastolic dysfunction across the whole spectrum. Our data extend previous observations into the prediabetic and normal range, and may be relevant to preventive approaches, as no effective treatment has been identified for diastolic heart failure once established.

Impact of polymorphisms of the major histocompatibility complex class II, interleukin-10, tumor necrosis factor-alpha and cytotoxic T-lymphocyte antigen-4 genes on inhibitor development in severe hemophilia A.

BACKGROUND: Approximately 25% of severe hemophilia A (HA) patients develop antibodies to factor VIII protein. PATIENTS: In the present case-controlled cohort study, 260 severely affected, mutation-type-matched HA patients were studied for association of human leukocyte antigen (HLA) class II molecules and polymorphisms in the genes encoding interleukin-10 (IL-10), tumor necrosis factor-alpha (TNF-alpha) and cytotoxic T-lymphocyte antigen-4 (CTLA-4) and development of inhibitors. RESULTS: Our results demonstrate a higher frequency of DRB1*15 and DQB1*0602 alleles as well as of the haplotype DRB1*15/DQB1*0602 in inhibitor patients [odds ratio (OR) 1.9; P < 0.05]. In TNF-alp[ha, the A allele of the 308G>A polymorphism was found with higher frequency in the inhibitor cohort (0.22 vs. 0.13, OR 1.80). This finding was more pronounced for the homozygous A/A genotype (OR 4.7). For IL-10, the 1082G allele was observed more frequently in patients with inhibitors (0.55 vs. 0.43; P = 0.008). The functional cytokine phenotype was determined for the first time, on the basis of the genetic background, and this showed that 12% of patients with inhibitors were high-TNF-alpha/high-IL-10 producers, as compared with 3% of non-inhibitor patients (OR 4.4). A trend for a lower frequency of the A allele of the CT60 polymorphism in CTLA-4 was found in inhibitor patients (0.42 vs. 0.50). CONCLUSIONS: In conclusion, the reported data clearly highlighted the participation of HLA molecules in inhibitor formation in a large cohort of patients. The higher frequencies of the 308G>A polymorphism in TNF-alpha and 1082A>G in IL-10 in inhibitor patients confirmed the earlier published data. The CT60 single-nucleotide polymorphism in CTLA-4 is of apparently less importance.

Genomic imbalances in 61 renal cancers from the proximal tubulus detected by comparative genomic hybridization.

Comparative genomic hybridization (CGH) has been applied to characterize 61 primary renal cell carcinomas derived histogenetically from the proximal tubulus. The tumor samples comprised 46 clear-cell renal cell carcinomas (ccRCCs) and 15 papillary renal cell carcinomas (pRCCs). Changes in the copy number of entire chromosomes or subregions were detected in 56 tumors (92%). In ccRCCs, losses of chromosome 3 or 3p (63%); 14q (30%); 9 (26%); 1 and 6 or 6q (17% each); 4 and 8 or 8p (15% each); 22 (11%); 2 or 2q and 19 (9% each); 7q, 10, 16, 17p, 18, and Y (7% each); and 5, 11, 13, 15, and 21 (4% each) were detected. Most frequent genomic gains in ccRCC were found on chromosome 5 (63%); 7 (35%); 1 or 1q (33%); 2q (24%); 8 or 8q, 12, and 20 (20% each); 3q (17%); 16 (15%); 19 (13%); 6 and 17 or 17q (11% each); and 4, 10, 11, 21, and Y (9% each). In pRCCs, gains in the copy number of chromosomes 7 and 17 (7/15, each) and 16 and 20 (6/15, each) were frequent. One pRCC showed amplification of subchromosome regions 2q22-->q33, 16q, 17q and the entire X chromosome. In pRCC, losses were less frequently seen than gains. Losses of chromosomes 1, 14, 15, and Y (3/15 each) and 2, 4, 6, and 13 (2/15 each) were observed. In ccRCCs, statistical evaluation revealed significant correlations of chromosomal imbalances with tumor stage and grade, i.e., a gain in copy number of chromosome 5 correlated positively with low tumor grade, whereas a gain of chromosomes 10 and 17 correlated positively with high tumor grade. Furthermore, loss of chromosome 4 correlated positively with high tumor stage.

Retrotransposon evolution in diverse plant genomes.

Retrotransposon or retrotransposon-like sequences have been reported to be conserved components of cereal centromeres. Here we show that the published sequences are derived from a single conventional Ty3-gypsy family or a nonautonomous derivative. Both autonomous and nonautonomous elements are likely to have colonized Poaceae centromeres at the time of a common ancestor but have been maintained since by active retrotransposition. The retrotransposon family is also present at a lower copy number in the Arabidopsis genome, where it shows less pronounced localization. The history of the family in the two types of genome provides an interesting contrast between "boom and bust" and persistent evolutionary patterns.

Implantable dual-chamber cardioverter-defibrillator-pacemaker.

The fifth generation of implantable cardioverter-defibrillators offer enhanced modes of detection of atrial and ventricular arrhythmias, antitachycardia pacing and shocks, multiprogrammability, intracardiac electrogram storage, and all functions of antibradycardia dual-chamber pacing including rate responsiveness and mode switching. There is no consensus on the indications for dual-chamber pacemaker defibrillator systems. This review focuses on the four major options of newer devices that might benefit patients: 1) permanent dual-chamber pacing in ischemic coronary disease patients, 2) detection and management of atrial fibrillation or other atrial tachyarrhythmias, 3) some newer indications for pacing, and 4) the suppression of inappropriate interventions. On the basis of published data, newer indications for the dual-chamber systems, advantages and limitations, and future perspectives are discussed.

[Fractional flow reserve as a deciding criterion for intervention in patients with 50% coronary stenoses and impaired myocardial perfusion]. / Die fraktionelle Flussreserve als Entscheidungskriterium zur Intervention bei Patienten mit 50%-igen Koronarstenosen und gestörter Myokardperfusion.

BACKGROUND: A fractional flow reserve (FFRmyo) < 0.75 is a well validated parameter for significance of coronary stenoses in cases of normal myocardial function. We used the FFRmyo limit in patients with impaired myocardial perfusion by myocardial infarction and/or hypertension for intermediate stenoses of the LAD for decision to PTCA and checked the indication by clinical follow-up. METHODS: In 20 pts (5 women) with chest pain and visual 50 D% LAD stenoses, the FFRmyo was obtained by using a RADI-Pressure-Wire, the CFR by a densitometric technique (HODGSON), and the geometry of stenosis (minimal lumen diameter and diameter stenosis) by quantitative coronary angiography (QCA). EF and the kinetics of the anterolateral wall (expressed as radial shortening fraction) were measured by laevography. RESULTS: The mean age of our 20 pts. was 59.4 years: 13 of the pts. (65%) had a history of hypertension, 9 (45%) pts. a history of myocardial infarction. The mean diameter stenosis was 50.8%. The mean value of CFR was 2.9. The FFRmyo ranged from 0.66 to 0.90, the mean value was 0.78. The 12 pts. with FFRmyo > or = 0.75 (60%, group A) were treated with the usual anti-anginal medications. A PTCA was performed only in patients with FFRmyo < 0.75 (N = 8 (40%), group B). Except for one pt. with instent restenosis, in the 7 pts. with denovo stenoses stent implantation was performed. Significant differences between the groups A and B were seen only for the total number of myocardial infarctions (8/12 vs. 1/8) and diameter stenosis (48.5% vs. 54.3%). All lesions of group B had a diameter stenosis of 50% or higher. CFR correlated significantly with the radial shortening fraction (r = 0.75), minimal lumen diameter (r = -0.51) and diameter stenosis (r = -0.46). FFRmyo correlated with diameter stenosis (r = -0.47) only. All pts. treated with PTCA were primarily free of pain or reduced angina at least 1 CCS stage; only one developed an angina due to a restenosis (74 D%) 2 months after PTCA and stent implantation. The pts. of group A did not get worse, nor were they readmitted within 6 to 13 months after catheterization. CONCLUSIONS: Pts. with 50 D% stenoses, impaired myocardial perfusion and FFRmyo < 0.75 had a good long-term benefit concerning clinical and angiographic result. No pts. with FFRmyo < 0.75 had a D% lower than 50; therefore, the PTCA of intermediate stenoses without quantification must be avoided. CFR is not helpful for a decision to PTCA in such cases, because a normal value of CFR is relevant only.

[Catheter ablation of supraventricular tachyarrhythmias]. / Katheterablation von supraventrikulären Tachyarrhythmien.

The term "supraventricular tachyarrhythmia" summarizes electrophysiologically different arrhythmias. After detection of the mechanism of the present arrhythmia, the weak part of the reentrant circuit has to be identified using different mapping techniques. The catheter ablation is widely used as focal ablation (sinus tachycardia, ectopic atrial tachycardia, focal atrial fibrillation) or for interruption of conducting pathways (accessory pathways, AV nodal reentrant tachycardia). A single ablation line should be created in isthmus-dependent atrial flutter or in incisional tachycardias, which is less used now-a-days. Multiple ablation lines are needed for ablation of atrial fibrillation, which is a method investigated in arrhythmia centers only. Some arrhythmias are less well understood, not localizable and therefore not curatively treated with ablation techniques. Newer three-dimensional mapping methods may help in this situation. The challenge at the present time is the catheter ablation of atrial fibrillation.

[Alcohol concentration in the coronary sinus after transarterial ablation of septal hypertrophy in hypertrophic obstructive cardiomyopathy]. / Die Alkoholkonzentration im Sinus coronarius nach transarterieller Ablation der Septumhypertrophie bei hypertropher obstruktiver Kardiomyopathie.

BACKGROUND AND OBJECTIVE: The size of the resulting myocardial necrosis varies after percutaneous transarterial ablation (PTA) of hypertrophied septum in patients with hypertrophic obstructive cardiomyopathy (HOCM). It was the aim of this study to discover whether the alcohol concentration in coronary sinus (CS) blood is a useful and appropriate parameter and what conclusions can be drawn from it. PATIENTS AND METHODS: PTA was done in four patients (two women and two men, aged 30-53 years) with HOCM. Before the intervention the gradient across the left ventricular outflow tract ranged form 20 to 80 mmHg, postextrasystolic it ranged from 40 to 180 mmHg. 1 x 2 ml ethanol was injected into the first septal branch in 3 patients, 2 x 2 ml in one. The alcohol concentration in coronary sinus blood was measured every 30 sec for up to 5 min before and after ablation. The amounts were compared with the size of the akinetic area in the echocardiogram and the maximal value of creatine kinase, as a measure of the size of myocardial necrosis. RESULTS: The left ventricular outflow gradient was reduced in all patients, to 0-30 mmHg and postextrasystolic to 30-90 mmHg. A pacemaker had to be implanted in one patient who developed a 3 degrees AV block. The alcohol concentration in coronary sinus blood ranged from maximally 1.53 and 0.23 per thousand after 30 sec and then fell to 0.56-0.12 per thousand after 5 min. The patient with the highest CS alcohol concentration also had the highest maximal value for creatine kinase (68 mumol/l) and the largest akinetic area in the echocardiogram. CONCLUSION: The extent of myocardial necrosis can probably be estimated from the CS blood concentration of alcohol after alcohol ablation. If, after the first injection, high alcohol concentrations are measured, further alcohol injections are not indicated.

[Paradoxical respiratory response, changes in heart rate and skin circulation in progressive isocapnic hypoxia in sleep apnea patients]. / Paradoxe Atemantwort, Herzfrequenz- und Hautdurchblutungsänderung unter progressiver isokapnischer Hypoxie bei Schlafapnoe-Patienten.

In 73 patients with sleep apnea syndrome, lung function tests, night-time polysomnography for determining the apnea index (AI), hyperoxic progressive hypercapnia tests under rebreathing conditions, and, after a short pause, isocapnic progressive hypoxia tests were carried out. The objective of these examinations was to study peripheral and central chemosensitivity, changes in heart rate and capillary cutaneous circulation under isocapnic hypoxia in patients with sleep apnea syndrome (SAS). The following linear relationships were presupposed for the evaluation: for peripheral chemosensitivity between SaO2 decrease and the increase in respiratory minute volume (VE) and for central chemosensitivity between PETCO2 rise and VE increase. Of the SAS patients with an AI > or = 10, 22.5% did not react to the hypoxia test with and increase in VE but rather with a decrease in the respiratory minute volume. This patient group exhibited a positive correlation between an increase in capillary cutaneous circulation and an increase in heart rate during the hypoxia test. The hypoxic respiratory response behavior is independent of the hypercapnic respiratory response, age, Broca index, initial heart rate, blood pressure, pulmonary function values, and the size of the apnea index. The results are discussed in the context of a reduced peripheral chemosensitivity and an associated reduced sympathetic activation.