Lead Reconstruction Using Artificial Neural Networks for Ambulatory ECG Acquisition.

One of the most powerful techniques to diagnose cardiovascular diseases is to analyze the electrocardiogram (ECG). To increase diagnostic sensitivity, the ECG might need to be acquired using an ambulatory system, as symptoms may occur during a patient's daily life. In this paper, we propose using an ambulatory ECG (aECG) recording device with a low number of leads and then estimating the views that would have been obtained with a standard ECG location, reconstructing the complete Standard 12-Lead System, the most widely used system for diagnosis by cardiologists. Four approaches have been explored, including Linear Regression with ECG segmentation and Artificial Neural Networks (ANN). The best reconstruction algorithm is based on ANN, which reconstructs the actual ECG signal with high precision, as the results bring a high accuracy (RMS Error < 13 µV and CC > 99.7%) for the set of patients analyzed in this paper. This study supports the hypothesis that it is possible to reconstruct the Standard 12-Lead System using an aECG recording device with less leads.

Joint statement for assessing and managing high blood pressure in children and adolescents: Chapter 2. How to manage high blood pressure in children and adolescents.

The joint statement is a synergistic action between HyperChildNET and the European Academy of Pediatrics about the diagnosis and management of hypertension in youth, based on the European Society of Hypertension Guidelines published in 2016 with the aim to improve its implementation. Arterial hypertension is not only the most important risk factor for cardiovascular morbidity and mortality, but also the most important modifiable risk factor. Early hypertension-mediated organ damage may already occur in childhood. The duration of existing hypertension plays an important role in risk assessment, and structural and functional organ changes may still be reversible or postponed with timely treatment. Therefore, appropriate therapy should be initiated in children as soon as the diagnosis of arterial hypertension has been confirmed and the risk factors for hypertension-mediated organ damage have been thoroughly evaluated. Lifestyle measures should be recommended in all hypertensive children and adolescents, including a healthy diet, regular exercise, and weight loss, if appropriate. If lifestyle changes in patients with primary hypertension do not result in normalization of blood pressure within six to twelve months or if secondary or symptomatic hypertension or hypertension-mediated organ damage is already present, pharmacologic therapy is required. Regular follow-up to assess blood pressure control and hypertension-mediated organ damage and to evaluate adherence and side effects of pharmacologic treatment is required. Timely multidisciplinary evaluation is recommended after the first suspicion of hypertension. A grading system of the clinical evidence is included.

Joint statement for assessing and managing high blood pressure in children and adolescents: Chapter 1. How to correctly measure blood pressure in children and adolescents.

The joint statement is a synergistic action between HyperChildNET and the European Academy of Pediatrics about the diagnosis and management of hypertension in youth, based on the European Society of Hypertension Guidelines published in 2016 with the aim to improve its implementation. The first and most important requirement for the diagnosis and management of hypertension is an accurate measurement of office blood pressure that is currently recommended for screening, diagnosis, and management of high blood pressure in children and adolescents. Blood pressure levels should be screened in all children starting from the age of 3 years. In those children with risk factors for high blood pressure, it should be measured at each medical visit and may start before the age of 3 years. Twenty-four-hour ambulatory blood pressure monitoring is increasingly recognized as an important source of information as it can detect alterations in circadian and short-term blood pressure variations and identify specific phenotypes such as nocturnal hypertension or non-dipping pattern, morning blood pressure surge, white coat and masked hypertension with prognostic significance. At present, home BP measurements are generally regarded as useful and complementary to office and 24-h ambulatory blood pressure for the evaluation of the effectiveness and safety of antihypertensive treatment and furthermore remains more accessible in primary care than 24-h ambulatory blood pressure. A grading system of the clinical evidence is included.

Comparison of validation protocols for blood pressure measuring devices in children and adolescents.

Accuracy of blood pressure (BP) measurement is important for the evaluation of hypertension in children and adolescents, and it is critically dependent upon the accuracy of the BP measuring device. A device that could pass validated protocols with reliable accuracy would be desirable in clinical and research settings. Several scientific organizations have published recommendations on the validation of different BP measuring devices. Most of them focus on adults but separate recommendations and validation criteria for BP devices intended for use in children and adolescents are included in some validation protocols. In this review, we compare the validation criteria for BP measuring devices among consensus documents from different scientific organizations focusing on the pediatric population and we discuss the evidence gaps targeting the needs for validated BP measuring devices in children and adolescents. We also highlight common pitfalls in the validation studies of BP measuring devices in children and adolescents using the example of office BP devices.

Correction of systematic spatial noise in push-broom hyperspectral sensors: application to CHRIS/PROBA images.

Hyperspectral remote sensing images are affected by different types of noise. In addition to typical random noise, nonperiodic partially deterministic disturbance patterns generally appear in the data. These patterns, which are intrinsic to the image formation process, are characterized by a high degree of spatial and spectral coherence. We present a new technique that faces the problem of removing the spatially coherent noise known as vertical striping, usually found in images acquired by push-broom sensors. The developed methodology is tested on data acquired by the Compact High Resolution Imaging Spectrometer (CHRIS) onboard the Project for On-board Autonomy (PROBA) orbital platform, which is a typical example of a push-broom instrument exhibiting a relatively high noise component. The proposed correction method is based on the hypothesis that the vertical disturbance presents higher spatial frequencies than the surface radiance. A technique to exclude the contribution of the spatial high frequencies of the surface from the destriping process is introduced. First, the performance of the proposed algorithm is tested on a set of realistic synthetic images with added modeled noise in order to quantify the noise reduction and the noise estimation accuracy. Then, algorithm robustness is tested on more than 350 real CHRIS images from different sites, several acquisition modes (different spatial and spectral resolutions), and covering the full range of possible sensor temperatures. The proposed algorithm is benchmarked against the CHRIS reference algorithm. Results show excellent rejection of the noise pattern with respect to the original CHRIS images, especially improving the removal in those scenes with a natural high contrast. However, some low-frequency components still remain. In addition, the developed correction model captures and corrects the dependency of the noise patterns on sensor temperature, which confirms the robustness of the presented approach.

ETAT: Expository Text Analysis Tool.

Qualitative methods that analyze the coherence of expository texts not only are time consuming, but also present challenges in collecting data on coding reliability. We describe software that analyzes expository texts more rapidly and produces a notable level of objectivity. ETAT (Expository Text Analysis Tool) analyzes the coherence of expository texts. ETAT adopts a symbolic representational system, known as conceptual graph structures. ETAT follows three steps: segmentation of a text into nodes, classification of the unidentified nodes, and linking the nodes with relational arcs. ETAT automatically constructs a graph in the form of nodes and their interrelationships, along with various attendant statistics and information about noninterrelated, isolated nodes. ETAT was developed in Java, so it is compatible with virtually all computer systems.