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To determine the diagnostic and prognostic value of natriuretic peptides in patients with Chagas' disease (CD), the authors first measured atrial (ANP), B-type (BNP), and C-type natriuretic peptide (CNP) and compared their diagnostic and prognostic capacity with that in other dilated cardiomyopathies (DCM). The CD and DCM patients were subdivided according to their New York Heart Association (NYHA) classification. Circulating ANP and more pronounced BNP, but not CNP, were increased in CD and DCM patients in relation to NYHA class. Importantly, ANP and BNP were already significantly elevated in CD patients without systolic ventricular dysfunction. All 3 natriuretic peptides were correlated with echocardiographic parameters in CD patients. While ANP and BNP have high predictive value for mortality and necessity for heart transplant in CD, CNP can not predict them. Thus, ANP and BNP rather than CNP could be used as valuable molecular markers to identify asymptomatic CD patients for early therapy and predict clinical outcomes.

The introduction of telemanipulator systems into cardiac surgery enabled the heart surgeon to perform minimally invasive procedures with high precision and stereoscopic view. For further improvement and especially for inclusion of autonomous action sequences, implementation of force-feedback is necessary. The aim of our study was to provide a robotic scenario giving the surgeon an impression very similar to open procedures (high immersion) and to enable autonomous surgical knot tying with delicate suture material. In this experimental set-up the feasibility of autonomous surgical knot tying is demonstrated for the first time using stereoscopic view and force feedback., (Copyright 2005 John Wiley & Sons, Ltd.)

In this study heart rate variability (HRV) analysis was applied to characterize patients suffering from coronary heart disease (CHD), dilated cardiomyopathy (DCM) and patients who had survived an acute myocardial infarction (MI). On the basis of several HRV parameters, an optimal discrimination between the different kinds of cardiovascular diseases and between the diseases and healthy controls (HC) was derived by feature selection and linear classification. For each task a small favourable subset of a set of 33 potentially interesting HRV measures was selected with the intention of improving the diagnostic value and facilitating the physiological interpretation of HRV analysis. Time- and frequency-domain parameters as well as parameters from non-linear dynamics were included in the analysis. With the expectation that different diseases are characterized by different phenomena, feature selection was applied for each task separately. Using the features optimal for one task to another task can reveal a loss in performance, but it turned out that one specific parameter set (set1: normalized low frequency LF/P and a non-linear variability measure WPSUM13) was applicable for all tasks, where diseased and healthy subjects have to be distinguished, without significant reduction in performance. This set seems to be a general marker for pathologic changes in HRV and might be used for early detection of heart diseases. The classification between different heart diseases requires another parameter set (set2: meanNN and sdaNN, reflecting the steady state behaviour of the heart rate and long and short term SEAR describing the spectral composition). However, the use of set1 for the separation of different kinds of diseases, where set2 is appropriate, led to significant reduction in performance and vice versa. This observation may be important for future developments of HRV measures especially suitable for the assessment of disease severity., (Copyright 2002 John Wiley & Sons, Ltd.)