Heart rate variability and nonlinear dynamic analysis in patients with stress-induced cardiomyopathy

• Published in: Medical & biological engineering & computing Vol. 50; no. 10; pp. 1037 - 1046
• Main Authors: Krstacic, Goran, Parati, Gianfranco, Gamberger, Dragan, Castiglioni, Paolo, Krstacic, Antonija, Steiner, Robert
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.10.2012; Springer Nature B.V
• Subjects: Aged; Analysis; Arrhythmias, Cardiac - diagnosis; Arrhythmias, Cardiac - etiology; Beta blockers; Biomedical and Life Sciences; Biomedical Engineering and Bioengineering; Biomedicine; Blood clots; Cardiology; Cardiomyopathy; Cardiovascular disease; Case-Control Studies; Chaos theory; Computer Applications; Coronary vessels; Electrocardiography; Electrocardiography - methods; Female; Fractals; Heart attacks; Heart rate; Hospitalization; Hospitals; Human Physiology; Humans; Imaging; Laboratories; Medical imaging; Middle Aged; Nonlinear Dynamics; Nonlinear systems; Original Article; Patients; Prognosis; Radiology; Signal Processing, Computer-Assisted; Studies; Takotsubo Cardiomyopathy - complications; Veins & arteries; Nonlinear dynamics; Stress-induced cardiomyopathy; Chaos theory; Heart rate variability; Takotsubo syndrome
• ISSN: 0140-0118; 1741-0444; 1741-0444
• DOI: 10.1007/s11517-012-0947-z

Complexity-based analyses may quantify abnormalities in heart rate variability (HRV). The aim of this study was to investigate the clinical and prognostic significances of dynamic HRV changes in patients with stress-induced cardiomyopathy Takotsubo syndrome (TS) by means of linear and nonlinear analysis. Patients with TS were included in study after complete noninvasive and invasive cardiovascular diagnostic evaluation and compared to an age and gender matched control group of healthy subjects. Series of R–R interval and of ST–T interval values were obtained from 24-h ECG recordings after digital sampling. HRV analysis was performed by ‘range rescaled analysis’ to determine the Hurst exponent, by detrended fluctuation analysis to quantify fractal long-range correlation properties, and by approximate entropy to assess time-series predictability. Short- and long-term fractal-scaling exponents were significantly higher in patients with TS in acute phases, opposite to lower approximate entropy and Hurst exponent, but all variables normalized in a few weeks. Dynamic HRV analysis allows assessing changes in complexity features of HRV in TS patients during the acute stage, and to monitor recovery after treatment, thus complementing traditional ECG and clinically analysis.