Peculiarities of electrocardiogram P-wave morphology analysis using principal component analysis

2011 ◽  
Vol 44 (2) ◽  
pp. e30
Author(s):  
Algimantas Krisciukaitis ◽  
Renata Simoliuniene ◽  
Alfonsas Vainoras ◽  
Liudas Gargasas
2007 ◽  
Vol 12 (4) ◽  
pp. 354-363 ◽  
Author(s):  
Fabrice Extramiana ◽  
Abdeddayem Haggui ◽  
Pierre Maison-Blanche ◽  
Rémi Dubois ◽  
Seiji Takatsuki ◽  
...  

2007 ◽  
Vol 40 (6) ◽  
pp. S81 ◽  
Author(s):  
Mads P. Andersen ◽  
Joel Xue ◽  
Claus Graff ◽  
Thomas B. Hardahl ◽  
Michael Christiansen ◽  
...  

2012 ◽  
Vol 48 (2) ◽  
pp. 125-131
Author(s):  
Federica Censi ◽  
Giovanni Calcagnini ◽  
Pietro Bartolini ◽  
Renato Pietro Ricci ◽  
Massimo Santini

2010 ◽  
Vol 49 (02) ◽  
pp. 161-167
Author(s):  
R. Simoliuniene ◽  
M. Tamosiunas ◽  
V. Saferis ◽  
A. Vainoras ◽  
L. Gargasas ◽  
...  

Summary Background: Cardiac output is controlled by the autonomic nervous system by changing the heart rate and/or the contractions of the heart muscle in response to the hemodynamic needs of the whole body. Malfunction of these mechanisms causes the postural orthostatic tachycardia syndrome and/or the chronic fatigue syndrome. Evaluation of functionality and efficiency of the control mechanisms could give valuable diagnostic information in the early stages of dysfunction of the heart control systems and help to monitor the healing process in rehabilitation period after interventions. Objectives: In this study we demonstrate how P-wave changes evoked by an ortho-static test could be quantitatively evaluated by using the method based on the principal component analysis. Methods: ECG signals were recorded during an orthostatic test performed according to the typical protocol in three groups of volunteer subjects representing healthy young and older persons, part of which had transient periods of supraventricular arrhythmias. Quantitative evaluation of P-wave morphology changes was performed by means of principal component analysis-based method. Results: Principal component-based estimates showed certain variety of P-wave shape during orthostatic test, what revealed a possibility to evaluate the properties of para-sympathetic heart control. Conclusions: Quantitative evaluation of ECG P-wave changes evoked by an orthostatic test by using a newly developed method provides a quantitative estimate for functionality and efficiency of the heart rate control mechanisms. The method could be used in eHealth systems.


2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
Jacek Wodecki ◽  
Justyna Hebda-Sobkowicz ◽  
Adam Mirek ◽  
Radosław Zimroz ◽  
Agnieszka Wyłomańska

Seismic events are phenomena which commonly occur in the mining industry. Due to their dangerous character, such information as the energy of the potential event, the location of hazardous regions with higher seismic activity is considered valuable. However, the acquisition of this information is almost impossible without the ability to detect the onset time of the seismic event. The main objectives of algorithms in finding P-wave are high accuracy, reasonable time of operation, and automatic detection of wave arrival. In this paper, an innovative method which incorporates principal component analysis (PCA) with time-frequency representation of the signal is proposed. Due to the significant difference between the spectra of recorded seismic wave and pure noise which precedes the event, time-frequency representation allows for better accuracy of signal change detection. However, with an additional domain, the complexity rises. Thus, the incorporation of PCA (which is known for high efficiency in lowering data dimensions while maintaining original information) seems to be recommended. In order to show the feasibility of the method, it will be tested on real data originating from monitoring system used in underground mine.


2009 ◽  
Vol 05 (01) ◽  
Author(s):  
Krisciukaitis A ◽  
Simoliuniene R ◽  
Tamosiunas M ◽  
Saferis V ◽  
Vainoras A ◽  
...  

VASA ◽  
2012 ◽  
Vol 41 (5) ◽  
pp. 333-342 ◽  
Author(s):  
Kirchberger ◽  
Finger ◽  
Müller-Bühl

Background: The Intermittent Claudication Questionnaire (ICQ) is a short questionnaire for the assessment of health-related quality of life (HRQOL) in patients with intermittent claudication (IC). The objective of this study was to translate the ICQ into German and to investigate the psychometric properties of the German ICQ version in patients with IC. Patients and methods: The original English version was translated using a forward-backward method. The resulting German version was reviewed by the author of the original version and an experienced clinician. Finally, it was tested for clarity with 5 German patients with IC. A sample of 81 patients were administered the German ICQ. The sample consisted of 58.0 % male patients with a median age of 71 years and a median IC duration of 36 months. Test of feasibility included completeness of questionnaires, completion time, and ratings of clarity, length and relevance. Reliability was assessed through a retest in 13 patients at 14 days, and analysis of Cronbach’s alpha for internal consistency. Construct validity was investigated using principal component analysis. Concurrent validity was assessed by correlating the ICQ scores with the Short Form 36 Health Survey (SF-36) as well as clinical measures. Results: The ICQ was completely filled in by 73 subjects (90.1 %) with an average completion time of 6.3 minutes. Cronbach’s alpha coefficient reached 0.75. Intra-class correlation for test-retest reliability was r = 0.88. Principal component analysis resulted in a 3 factor solution. The first factor explained 51.5 of the total variation and all items had loadings of at least 0.65 on it. The ICQ was significantly associated with the SF-36 and treadmill-walking distances whereas no association was found for resting ABPI. Conclusions: The German version of the ICQ demonstrated good feasibility, satisfactory reliability and good validity. Responsiveness should be investigated in further validation studies.


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