Related Experiment Video
Updated: Feb 11, 2026
04:16
Electrocardiogram Recordings in Anesthetized Mice using Lead II
Published on: June 20, 2020
14.3K
Dynamical cross-correlations between RR and QT intervals in long-term electrocardiogram recordings.
Jimi Kokkonen1, Jiyeong Kim-Poikkimäki1, Teemu Pukkila1
1Computational Physics Laboratory, Tampere University, P.O. Box 600, FI-33014, Tampere, Finland.
Scientific Reports
|February 9, 2026
Summary
The study found that previous heartbeats (RR intervals) significantly influence the current heart
Area of Science:
- Cardiology and Biomedical Engineering
- Physiological Signal Processing
- Nonlinear Dynamics
Background:
- The dynamic interplay between RR and QT intervals is vital for electrocardiogram (ECG) interpretation and cardiac condition management.
- Short-range, beat-to-beat coupling between these intervals provides critical insights into cardiac electrophysiology.
- Previous RR intervals influence current QT intervals, a phenomenon observed in RR-QT transfer entropy studies.
Purpose of the Study:
- To investigate the short-range, beat-to-beat coupling between RR and QT intervals using time-lagged cross-correlation (TLCC) analysis.
- To quantify the relationship between QT intervals and preceding/succeeding RR intervals across various time lags.
- To establish a model-free characterization of normal RR-QT dynamics in healthy individuals.
Main Methods:
- Long-term ECG recordings from 202 healthy subjects were analyzed.
- Time-lagged cross-correlation (TLCC) analysis was employed to assess RR-QT interval relationships.
- The smoothness priors method was used for data preprocessing to preserve short-term dynamics.
Main Results:
- Highest RR-QT cross-correlations were observed during maximal interval overlap.
- A significant negative lag correlation indicated that preceding RR intervals strongly influence current QT intervals.
- Aging was associated with significantly reduced RR-QT cross-correlations, while sex showed no significant differences.
Conclusions:
- Past RR intervals exert a stronger influence on current QT intervals than succeeding ones.
- Aging significantly impacts RR-QT coupling, leading to reduced cross-correlations.
- These findings provide a reference for normal RR-QT dynamics and may aid in developing/validating cardiac models.
Related Concept Videos
01:29Electrocardiogram
6.4K
An electrocardiogram (ECG or EKG) is a critical diagnostic tool that records the electrical signals produced by the heart during each heartbeat. This recording is achieved through electrodes placed strategically on the arms, legs, and chest. The electrocardiograph amplifies these signals and produces 12 distinct tracings, offering a comprehensive understanding of the heart's electrical activity.
Three major waveforms are present in a typical ECG recording: the P wave, the QRS complex, and...
Three major waveforms are present in a typical ECG recording: the P wave, the QRS complex, and...
6.4K
01:34Crossing Over
172.3K
Unlike mitosis, meiosis aims for genetic diversity in its creation of haploid gametes. Dividing germ cells first begin this process in prophase I, where each chromosome—replicated in S phase—is now composed of two sister chromatids (identical copies) joined centrally.
The homologous pairs of sister chromosomes—one from the maternal and one from the paternal genome—then begin to align alongside each other lengthwise, matching corresponding DNA positions in a process...
The homologous pairs of sister chromosomes—one from the maternal and one from the paternal genome—then begin to align alongside each other lengthwise, matching corresponding DNA positions in a process...
172.3K
01:28Electrocardiogram Fundamentals
1.6K
Introduction
An electrocardiogram (ECG) is a diagnostic tool for identifying cardiac conditions such as arrhythmias, conduction abnormalities, and myocardial ischemia.
Definition
An electrocardiogram (ECG) visualizes the heart's electrical activity by tracing the electrical movement associated with each heartbeat on a graph or monitor. As the heart beats, an electrical wave passes through it, correlating with the cardiac cycle events.
Parts of an ECG
An ECG utilizes electrodes on the skin...
An electrocardiogram (ECG) is a diagnostic tool for identifying cardiac conditions such as arrhythmias, conduction abnormalities, and myocardial ischemia.
Definition
An electrocardiogram (ECG) visualizes the heart's electrical activity by tracing the electrical movement associated with each heartbeat on a graph or monitor. As the heart beats, an electrical wave passes through it, correlating with the cardiac cycle events.
Parts of an ECG
An ECG utilizes electrodes on the skin...
1.6K
01:03Prediction Intervals
3.4K
The interval estimate of any variable is known as the prediction interval. It helps decide if a point estimate is dependable.
However, the point estimate is most likely not the exact value of the population parameter, but close to it. After calculating point estimates, we construct interval estimates, called confidence intervals or prediction intervals. This prediction interval comprises a range of values unlike the point estimate and is a better predictor of the observed sample value, y.
However, the point estimate is most likely not the exact value of the population parameter, but close to it. After calculating point estimates, we construct interval estimates, called confidence intervals or prediction intervals. This prediction interval comprises a range of values unlike the point estimate and is a better predictor of the observed sample value, y.
3.4K
02:20Correlations
36.5K
Correlation means that there is a relationship between two or more variables (such as ice cream consumption and crime), but this relationship does not necessarily imply cause and effect. When two variables are correlated, it simply means that as one variable changes, so does the other. We can measure correlation by calculating a statistic known as a correlation coefficient. A correlation coefficient is a number from -1 to +1 that indicates the strength and direction of the relationship between...
36.5K
01:27Correlation and Causation
42.9K
Statistical tests can calculate whether there is a relationship, or correlation, between independent and dependent variables. An indirect relationship of the variables signifies a correlation, while a direct relationship shows causation. If it is determined that no connection exists between the variables, then the correlation is a coincidence.
Correlation versus Causation
If the dependent variable increases or decreases when the independent variable increases, there is a positive or negative...
Correlation versus Causation
If the dependent variable increases or decreases when the independent variable increases, there is a positive or negative...
42.9K