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Titolo:
Scatterplots of RR and RT interval variability bring evidence for diverse non-linear dynamics of heart rate and ventricular repolarization duration in coronary heart disease
Autore:
Sosnowski, M; Czyz, Z; Tendera, M;
Indirizzi:
Silesian Med Ctr, Silesian Sch Med, Div Cardiol 3, PL-40635 Katowice, Poland Silesian Med Ctr Katowice Poland PL-40635 l 3, PL-40635 Katowice, Poland
Titolo Testata:
EUROPACE
fascicolo: 1, volume: 3, anno: 2001,
pagine: 39 - 45
SICI:
1099-5129(200101)3:1<39:SORARI>2.0.ZU;2-D
Fonte:
ISI
Lingua:
ENG
Soggetto:
MYOCARDIAL-INFARCTION; QT DISPERSION; VULNERABILITY; ALTERNANS; CHAOS;
Keywords:
complexity; temporal dispersion; computerised electrocardiograms;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Clinical Medicine
Citazioni:
27
Recensione:
Indirizzi per estratti:
Indirizzo: Sosnowski, M Silesian Med Ctr, Silesian Sch Med, Div Cardiol 3, Ziolowa St47, PL-40635Katowice, Poland Silesian Med Ctr Ziolowa St 47 Katowice Poland PL-40635 land
Citazione:
M. Sosnowski et al., "Scatterplots of RR and RT interval variability bring evidence for diverse non-linear dynamics of heart rate and ventricular repolarization duration in coronary heart disease", EUROPACE, 3(1), 2001, pp. 39-45

Abstract

Objective QT interval prolongation and increased spatial QT dispersion areimportant factors increasing the risk in coronary heart disease. The authors studied the spontaneous beat-to-beat variability of ventricular repolarization (RT intervals) in normal subjects and in patients after myocardial infarction (MI) in order to define the determinants of abnormal temporal dispersion. Methods Seventy-six patients with a history of MI (17 female, 59 male, aged 52 +/- 10 years) comprised the study group. Forty-seven patients had preserved left ventricular ejection fraction (EF greater than or equal to 40%, MI-A) and 29 patients had left ventricular dysfunction (EF<40%, MI-B). Twenty healthy volunteers (6 female, 14 male, aged 25+/-5 years) were included as the control group. An ECG signal of 512 heartbeats was recorded in the supine position. After analogue-to-digital conversion (16 bit, 2 kHz), the fiducial points of the R wave and T wave were determined. The RR and RT variability (V) assessed in the time domain as the standard deviations of RR and RT (ms), as well as the coefficients of scatterplots of RR and RT intervals. Results As expected, the standard deviation of RR was significantly reduced in MI patients. The magnitude of RTV in the time domain was similar in the controls and in both subgroups of MI patients. The complexity of heart rate variability (HRV) was slightly, but significantly, reduced in the MI-B group, but not significantly in the MI-A heart group. The complexity of RTV behaved in the opposite manner, being increased in both MI subgroups with the lower mean in the MI-B patients. The different behaviour of HRV and RTV was indicated by the increased ratio of RR/RT coefficients, which reached asignificantly greater value in the MI-B group. Conclusion The authors have described different patterns of scatterplot ofshort-term HRV and RTV in normal subjects, which confirmed that RTV is a less complex phenomenon than HRV. In patients after MI, the complexity of HRV diminishes, while the complexity of RTV increases. These opposing changesare more pronounced in patients with left ventricular dysfunction. A possible prognostic value of this feature is unknown and remains to be elucidated in future prospective studies. (Europace 2001; 3: 39-45) (C) 2001 The European Society of Cardiology.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 20/01/20 alle ore 21:58:23