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This study proposes an application of symbolic analysis to beat-to-beat heart rate variability data derived from 24h Holter recordings both in healthy and heart failure populations. Heart rate series are transformed in a sequence of six symbols via a uniform quantization procedure. Symbols are grouped in patterns lasting three cardiac cycles and these(More)
BACKGROUND The need for accurate risk stratification is heightened by the expanding indications for the implantable cardioverter defibrillator. The Multicenter Automatic Defibrillator Implantation Trial (MADIT) focused interest on patients with both depressed left ventricular ejection fraction (LVEF) and the presence of nonsustained ventricular tachycardia(More)
In this study, we applied time- and frequency-domain signal processing techniques to the analysis of respiratory and arterial O(2) saturation (Sa(O(2))) oscillations during nonapneic periodic breathing (PB) in 37 supine awake chronic heart failure patients. O(2) was administered to eight of them at 3 l/min. Instantaneous tidal volume and instantaneous(More)
We assessed the association of periodic breathing (PB) with mortality and hospital re-admissions in a large sample of patients enrolled in the European Community study HHH (Home or Hospital in Heart failure). A 24-hour cardiorespiratory recording was carried out in 443 clinically stable heart failure (HF) subjects (age: 60±11 years, NYHA class 2.4±0.6, LVEF(More)
The HHH (Home or Hospital in Heart failure) study is a European Community multicenter trial aimed at assessing in a population of chronic heart failure patients 3 incremental home telemonitoring strategies against usual clinical practice. End points are rehospitalization, quality of life, mortality and cost-efficacy. Easy accessibility by the patient and(More)
We computed 3 linear and 20 nonlinear HRV indexes on 24-h Holter recordings from 200 stable CHF patients (age 52+9 yrs, NYHA II-III, LVEF 24+6%) with the aim to assess i) the mutual interrelationships between these indexes and ii) their prognostic value towards cardiac death. We found high correlations between variables, with potential bias in fitting(More)
We study the phase-synchronization properties of systolic and diastolic arterial pressure in healthy subjects. We find that delays in the oscillatory components of the time series depend on the frequency bands that are considered, in particular we find a change of sign in the phase shift going from the very low frequency band to the high frequency band.(More)
In this paper, we consider systolic arterial pressure time series from healthy subjects and chronic heart failure patients, undergoing paced respiration, and show that different physiological states and pathological conditions may be characterized in terms of predictability of time series signals from the underlying biological system. We model time series(More)
To evaluate the relationship between lesion's severity and nonlinear indexes of HRV, 20 first-ever stroke subjects and 10 healthy subjects were studied. All patients, divided in two groups according to presence of single or multiple medium cerebral artery lesion, underwent to a 24-hour Holter ECG recording. All RR time series were analyzed by Poincarè Plot,(More)
In the present work a method is proposed for the estimation of the respiratory signal from the three ECG orthogonal leads. The vectorcardiogram loop was evaluated in correspondence of each QRS complex (in a time window of 120 ms centred around the R wave). The centre of gravity and the inertial axes of each loop were calculated. A set of 12 parameters (3(More)