Andrejs Fedjajevs

Mr. Andrejs Fedjajevs

Philips (Netherlands), Amsterdam, Noord-Holland, The Netherlands
orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 December 2017 in Science Advances
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PKPieter Kruizinga
Pieter Kruizinga
PMPim van der Meulen
Pim van der Meulen
AFAndrejs Fedjajevs
Andrejs Fedjajevs
FMFrits Mastik
Frits Mastik
GSGeert Springeling
Geert Springeling
GLGeert Leus
Geert Leus
Compressive 3D ultrasound imaging is possible with only one sensor and a simple aperture coding mask.

19 December 2020 in Sensors
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AFAndrejs Fedjajevs
Andrejs Fedjajevs
WGWillemijn Groenendaal
Willemijn Groenendaal
CACarlos Agell
Carlos Agell
EHEvelien Hermeling
Evelien Hermeling
Reliable and diverse labeled reference data are essential for the development of high-quality processing algorithms for medical signals, such as electrocardiogram (ECG) and photoplethysmogram (PPG). Here, we present the Platform for Analysis and Labeling of Medical time Series (PALMS) designed in Python. Its graphical user interface (GUI) facilitates three main types of manual annotations—(1) fiducials, e.g., R-peaks of ECG; (2) events with an adjustable duration, e.g., arrhythmic episodes; and (3) signal quality, e.g., data parts corrupted by motion artifacts. All annotations can be attributed to the same signal simultaneously in an ergonomic and user-friendly manner. Configuration for different data and annotation types is straightforward and flexible in order to use a wide range of data sources and to address many different use cases. Above all, configuration of PALMS allows plugging-in existing algorithms to display outcomes of automated processing, such as automatic R-peak detection, and to manually correct them where needed. This enables fast annotation and can be used to further improve algorithms. The GUI is currently complemented by ECG and PPG algorithms that detect characteristic points with high accuracy. The ECG algorithm reached 99% on the MIT/BIH arrhythmia database. The PPG algorithm was validated on two public databases with an F1-score above 98%. The GUI and optional algorithms result in an advanced software tool that allows the creation of diverse reference sets for existing datasets.

29 June 2022 in Sensors
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Israel Campero JuradoIsrael Campero Jurado
Israel Campero Jurado
AFAndrejs Fedjajevs
Andrejs Fedjajevs
JVJoaquin Vanschoren
Joaquin Vanschoren
ABAarnout Brombacher
Aarnout Brombacher
Nowadays, even with all the tremendous advances in medicine and health protocols, cardiovascular diseases (CVD) continue to be one of the major causes of death. In the present work, we focus on a specific abnormality: ST-segment deviation, which occurs regularly in high-performance athletes and elderly people, serving as a myocardial infarction (MI) indicator. It is usually diagnosed manually by experts, through visual interpretation of the printed electrocardiography (ECG) signal. We propose a methodology to detect ST-segment deviation and quantify its scale up to 1 mV by extracting statistical, point-to-point beat characteristics and signal quality indexes (SQIs) from single-lead ECG. We do so by applying automated machine learning methods to find the best hyperparameter configuration for classification and regression models. For validation of our method, we use the ST-T database from Physionet; the results show that our method obtains 98.30% accuracy in the case of a multiclass problem and 99.87% accuracy in the case of binarization.