Jaroslaw Piskorski

Heart rate asymmetry by Poincaré plots of RR intervals.

Abstract The Poincaré plot is a widely used method for visualizing and calculating heart rate variability and for investigating the oscillatory nature of heart action. We show that the Poincaré plot produced using physiological data for RR intervals is asymmetric. This suggests that the processes of heart rate acceleration (shortening of consecutive RR intervals) and deceleration (prolongation of successive RR intervals) might be asymmetric. To investigate this phenomenon, we define descriptors quantifying the heart rate asymmetry and present the results of a study involving 5-min ECG recordings of 50 healthy subjects in which, despite of the shortness of the recordings, the asymmetry is clearly visible.

How to strengthen or weaken the HRV dependence on heart rate — Description of the method and its perspectives

a Department of Cardiology, Regional Medical Center, Opole, Poland b Institute of Physics, Wroclaw University of Technology, Wroclaw, Poland c Instytut Fizyki imienia Mariana Smoluchowskiego and Mark Kac Complex Systems Research Center, Uniwersytet Jagiellonski, ulica Reymonta 4, PL-30-059 Krakow, Poland d 1. Medizinische Klinik und Deutsches Herzzentrum München der Technischen Universität München, Munich, Germany e Department of Cardiology-Intensive Therapy, University School of Medicine, Poznan, Poland f Institute of Physics, University of Zielona Gora, Zielona Gora, Poland

Heart rate deceleration runs for postinfarction risk prediction

UNLABELLED A method for counting episodes of uninterrupted beat-to-beat heart rate decelerations was developed. METHODS The method was set up and evaluated using 24-hour electrocardiogram Holter recordings of 1455 (training sample) and 946 (validation sample) postinfarction patients. During a median follow-up of 24 months, 70, 46, and 19 patients of the training sample suffered from total, cardiac, and sudden cardiac mortality, respectively. In the validation sample, these numbers were 39, 25, and 15. Episodes of consecutive beat-to-beat heart rate decelerations (deceleration runs [DRs]) were characterized by their length. RESULTS Deceleration runs of 2 to 10 cycles were significantly less frequent in nonsurvivors. Multivariate model of DRs of 2, 4, and 8 cycles identified low-, intermediate-, and high-risk groups. In these groups of the training sample, the total mortalities were 1.8%, 6.1%, and 24%, respectively. In the validation sample, these numbers were 1.8%, 4.1%, and 21.9%. CONCLUSION Infrequent DRs during 24-hour Holter indicate high risk of postinfarction mortality.

Asymmetric properties of long-term and total heart rate variability

We report on two new physiological phenomena: the long-term and total heart rate asymmetry, which describe a significantly larger contribution of heart rate accelerations to long-term and total heart rate variability. In addition to the existing pair of indices,

Asymmetric features of short-term blood pressure variability.

{\text {SD1}}_{\rm d}, {\text {SD1}}_{\rm a},

Arterial stiffness, central hemodynamics and wave reflection in normal pregnancy and control nonpregnant women

which are based on partitioning short-term variance, we introduce two other pairs of descriptors based on partitioning long-term (

Compensatory properties of heart rate asymmetry

{\text {SD2}}_{\rm d}, {\text {SD2}}_{\rm a}