The 2009 European Guidelines on Diagnosis and Treatment of Pulmonary Hypertension have been adopted for Germany. The guidelines contain detailed recommendations for the diagnosis of pulmonary hypertension. However, the practical implementation of the European Guidelines in Germany requires the consideration of several country-specific issues and already existing novel data. This requires a detailed commentary to the guidelines, and in some aspects an update already appears necessary. In June 2010, a Consensus Conference organized by the PH working groups of the German Society of Cardiology (DGK), the German Society of Respiratory Medicine (DGP) and the German Society of Pediatric Cardiology (DGPK) was held in Cologne, Germany. This conference aimed to solve practical and controversial issues surrounding the implementation of the European Guidelines in Germany. To this end, a number of working groups was initiated, one of which was specifically dedicated to the non-invasive diagnosis of pulmonary hypertension. This manuscript describes in detail the results and recommendations of the working group which were last updated in October 2011.

BACKGROUND When assessing the function of the cardiovascular system, cardiac output (CO) is a substantial parameter. For its determination, numerous non-invasive techniques have been proposed in the recent years including inert gas rebreathing (IGR) and impedance cardiography (ICG). The aim of our study was to evaluate whether a novel ICG algorithm (electrical velocimetry) and IGR can be used interchangeably in the clinical setting. METHODS A total of 120 consecutive stable patients were included resulting in two pairs of repeated non-invasive cardiac output measurements. RESULTS The mean CO was 5.0 ± 1.2 l/min (range 2.6-8.6 l/min) using IGR and 4.4 ± 1.1 l/min (1.7-7.4 l/min) using ICG, respectively. Bland-Altman analysis revealed an acceptable agreement with a mean bias of 0.6 ± 1.2 l/min. We found a high reproducibility with a mean bias of 0.2 ± 0.7 l/min for IGR and 0.0 ± 0.3 l/min for ICG (p < 0.001), respectively. There was a statistically significant difference for unphysiological circulatory conditions represented by values of 2.6-4.1 l/min and 5.6-8.6 l/min. CONCLUSIONS Both non-invasive techniques are associated with low operating costs and require only a few expendable items for the rapid determination of cardiac function. We found an acceptable agreement between IGR and ICG as well as a high reproducibility, which was statistically significant higher for ICG. For cardiac output states exceeding the physiological range, we found a statistically significant difference. Consequently, values of cardiac function determined by either method should not be used interchangeably in the clinical setting.

Although there are substantial differences between the magnetospheres of Jupiter and Saturn, it has been suggested that cryovolcanic activity at Enceladus could lead to electrodynamic coupling between Enceladus and Saturn like that which links Jupiter with Io, Europa and Ganymede. Powerful field-aligned electron beams associated with the Io-Jupiter coupling, for example, create an auroral footprint in Jupiter's ionosphere. Auroral ultraviolet emission associated with Enceladus-Saturn coupling is anticipated to be just a few tenths of a kilorayleigh (ref. 12), about an order of magnitude dimmer than Io's footprint and below the observable threshold, consistent with its non-detection. Here we report the detection of magnetic-field-aligned ion and electron beams (offset several moon radii downstream from Enceladus) with sufficient power to stimulate detectable aurora, and the subsequent discovery of Enceladus-associated aurora in a few per cent of the scans of the moon's footprint. The footprint varies in emission magnitude more than can plausibly be explained by changes in magnetospheric parameters--and as such is probably indicative of variable plume activity.

Cardiac output (CO) is an important parameter for diagnosis and therapy of heart diseases, but it is still difficult to determine. Innocor, a novel noninvasive inert gas rebreathing (IGR) system, has shown promising results. However, the impact of pulmonary diseases on IGR remains unclear. The aim of the study therefore was to assess the accuracy and reliability of IGR in patients with distinct chronic lung disease. A total of 96 patients were enrolled, including 48 consecutive patients with variant lung diseases (group A) and 48 pair-matched pulmonary healthy patients (group B). CO was measured with cardiac magnetic resonance imaging (CMR) and IGR. Lung function testing was done by spirometry [FEV(1)/FVC (forced expiratory volume in one second/forced vital capacity), VC (vital capacity)] and determination of the diffusing capacity of the lung for carbon monoxide divided by alveolar volume (DLCO/VA). In group A we found a mean CO of 4.7 ± 1.3 L/min by IGR and 4.9 ± 1.2 L/min by CMR. Group B showed a mean CO of 4.8 ± 1.4 L/min by IGR and 5.0 ± 1.3 L/min by CMR. Bland-Altman analysis revealed good correspondence between CMR and IGR, with an average deviation of 0.1 ± 1.0 L/min in group A and 0.1 ± 1.0 L/min in group B (p = 0.99). Multiple regression analysis for the pulmonary parameters did not show a statistically significant impact on the mean bias of CO measurements (FEV(1)/FVC: r = 0.01, p = 0.91; VC: r = -0.2, p = 0.13; and DLCO/VA: r = 0.04, p = 0.82). IGR allows a feasible determination of CO even in patients with lung diseases. The accuracy of the IGR method is not influenced by either pulmonary obstructive and restrictive diseases or a reduced DLCO.

Objectives: Atrial fibrillation (AF) is one of the most frequent heart rhythm disorders. It potentially influences cardiac function and its measurement. Cardiac magnetic resonance imaging (CMR) has become the new gold standard for non-invasive assessment of cardiac output (CO). A novel inert gas rebreathing (IGR) device based on the Fick Principle also proved promising in patients in sinus rhythm (SR). The aim of our study was to compare the agreement of non-invasive CO measurements between CMR and IGR in AF patients. Methods: A total of 68 patients, 34 with AF and 34 pair-matched controls in SR, were included. Results: Bland-Altman analysis showed good agreement between both methods, with an average deviation of 0.2 +/-1.2 l/min in the AF group versus 0.3 +/-1.0 l/min in the SR group (p = 0.77). IGR demonstrated good agreement for CO between 2.0 and 5.4 l/min. However, in hyperdynamic circulatory conditions (CO >5.5 l/min), the increasing disagreement of IGR and CMR measurements reached statistical significance. Conclusions: Non-invasive CO measurements using CMR and IGR are feasible in patients suffering from AF. Good agreement was found between the two methods in an unselected cohort. Hyperdynamic circulatory conditions can lead to significant measurement differences which, however, do not affect the reproducibility of IGR.

BACKGROUND: USCOM, a novel continuous wave Doppler (CWD) device, has been introduced for noninvasive determination of cardiac output (CO). The present study aimed to compare the accuracy and reproducibility of the new device, using cardiovascular magnetic resonance imaging (CMR) as the noninvasive gold standard. METHODS AND RESULTS: The CO of 56 consecutive patients was prospectively determined by CWD either before or after CMR imaging. The CWD probe was placed in the suprasternal or supraclavicular notch aiming at the aortic valve. Valid CWD signals could be obtained in 45 patients yielding a CO of 5.3+/-1.1 L/min (range, 3.0-7.5 L/min) by CMR and 4.7+/-1.1 L/min by CWD (2.5-8.0 L/min, P =.004), respectively. CWD measurements showed an acceptable agreement with CMR (bias: 0.6+/-1.1 L/min) and a high reproducibility (bias: 0.1+/-0.4 L/min). Higher CO and body mass index (BMI) were identified as sources of inaccuracy in univariate analysis. By multivariate analysis, only CO(CMR) was found to be independently associated with larger variation. Estimated diameters of the left ventricular outflow tract (LVOT), a prerequisite for CO measurement by CWD, correlated only weakly with those measured by CMR. CONCLUSIONS: Continuous wave Doppler is a feasible technique for measuring cardiac function. Although the overall agreement with CMR was acceptable, CWD showed a trend to underestimate CO. The estimated LVOT diameter by CWD is likely to be an important source of error. Nevertheless, the CWD device could be of clinical use especially for detection of intraindividual hemodynamic changes since a high reproducibility could be demonstrated.

To investigate the universality of magnetic turbulence in space plasmas, we analyze seven time periods in the free solar wind under different plasma conditions. Three instruments on Cluster spacecraft operating in different frequency ranges give us the possibility to resolve spectra up to 300 Hz. We show that the spectra form a quasiuniversal spectrum following the Kolmogorov's law approximately k;{-5/3} at MHD scales, a approximately k;{-2.8} power law at ion scales, and an exponential approximately exp[-sqrt[krho_{e}]] at scales krho_{e} approximately [0.1,1], where rho_{e} is the electron gyroradius. This is the first observation of an exponential magnetic spectrum in space plasmas that may indicate the onset of dissipation. We distinguish for the first time between the role of different spatial kinetic plasma scales and show that the electron Larmor radius plays the role of a dissipation scale in space plasma turbulence.

Background: An easy, noninvasive and accurate technique for measuring cardiac output (CO) would be desirable for the diagnosis and therapy of cardiac diseases. Innocor, a novel inert-gas-rebreathing (IGR) system, has shown promising results in smaller studies. An extensive evaluation in a larger, less homogeneous patient collective is lacking. Methods: We prospectively assessed the accuracy and reproducibility of CO measurements obtained by IGR in 305 consecutive patients as compared to the noninvasive gold standard, cardiovascular magnetic resonance (CMR) imaging. Results: Bland-Altman analysis showed a good correspondence of the two methods for CO measurement with an average deviation of 0.2 +/- 1.0 liters/min (mean +/- SD) and a good reproducibility with a mean bias of 0.2 +/- 0.5 liters/min. The accuracy of the present measurements at rest was significantly better in the physiological range than in higher or lower CO ranges. The error levels set forth by current recommendations were exceeded. Conclusion: The data show that IGR measurements are easy to perform and show good agreement with CMR; however, the technique appears to be less accurate in extreme CO ranges at rest. The clinical importance of the IGR method remains to be proven by further studies.