Related Experiment Video
Updated: Jun 20, 2026
A Pre-Clinical Porcine Model of Orthotopic Heart Transplantation
Published on: April 27, 2019
Non-invasive pulse arrival time is associated with cardiac index in pediatric heart transplant patients with normal
Soon Bin Kwon1,2, Bennett Weinerman2,3, Daniel Nametz1,2
1Department of Neurology, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, United States of America.
Insights
Pulse Arrival Time (PAT) shows promise as a non-invasive method to estimate Cardiac Index (CI) in pediatric intensive care units. This study found PAT correlates with CI, offering a potential bedside tool for monitoring patients.
Area of Science:
- Pediatric critical care medicine
- Cardiovascular physiology
- Biomedical engineering
Background:
- Cardiac Index (CI) is crucial for assessing end-organ perfusion in pediatric intensive care units (PICUs).
- Current methods for CI determination are invasive and not routinely available at the bedside.
- A non-invasive surrogate for CI is needed for continuous patient monitoring.
Purpose of the Study:
- To evaluate Pulse Arrival Time (PAT) as a non-invasive surrogate for Cardiac Index (CI).
- To assess PAT's correlation with CI in pediatric patients with normal Ejection Fraction (EF).
- To explore the utility of routine physiologic data for non-invasive hemodynamic monitoring.
Main Methods:
- Collected electrocardiogram (ECG) and photoplethysmogram (PPG) signals from 20 pediatric patients.
- Derived continuous Pulse Arrival Time (PAT) from ECG and PPG waveforms.
- Calculated Pearson's correlation coefficients between PAT and Cardiac Index (CI), Heart Rate (HR), and Ejection Fraction (EF).
Main Results:
- A significant positive correlation was observed between PAT and CI (r=0.57, p<0.01).
- PAT indexed by HR (PAT × HR) showed a slightly improved correlation with CI (r=0.58, p<0.01).
- Correlations between HR and CI (r=0.22) and EF and CI (r=0.03) were not significant.
Conclusions:
- Pulse Arrival Time (PAT) demonstrates potential as a non-invasive, continuous surrogate marker for Cardiac Index (CI) at the PICU bedside.
- This pilot study suggests PAT may aid in monitoring hemodynamic status in critically ill children.
- Further investigation is required to validate PAT's clinical utility in diverse pediatric populations.
Abstract:
Objective.Cardiac Index (CI) is a key physiologic parameter to ensure end organ perfusion in the pediatric intensive care unit (PICU). Determination of CI requires invasive cardiac measurements and is not routinely done at the PICU bedside. To date, there is no gold standard non-invasive means to determine CI. This study aims to use a novel non-invasive methodology, based on routine continuous physiologic data, called Pulse Arrival Time (PAT) as a surrogate for CI in patients with normal Ejection Fraction (EF).Approach.Electrocardiogram (ECG) and photoplethysmogram (PPG) signals were collected from beside monitors at a sampling frequency of 250 samples per second. Continuous PAT, derived from the ECG and PPG waveforms was averaged per patient. Pearson's correlation coefficient was calculated between PAT and CI, PAT and heart rate (HR), and PAT and EF.Main Results.Twenty patients underwent right heart cardiac catheterization. The mean age of patients was 11.7 ± 5.4 years old, ranging from 11 months old to 19 years old, the median age was 13.4 years old. HR in this cohort was 93.8 ± 17.0 beats per minute. The average EF was 54.4 ± 9.6%. The average CI was 3.51 ± 0.72 l min-1m-2, with ranging from 2.6 to 4.77 l min-1m-2. The average PAT was 0.31 ± 0.12 s. Pearson correlation analysis showed a positive correlation between PAT and CI (0.57,p< 0.01). Pearson correlation between HR and CI, and correlation between EF and CI was 0.22 (p= 0.35) and 0.03 (p= 0.23) respectively. The correlation between PAT, when indexed by HR (i.e. PAT × HR), and CI minimally improved to 0.58 (p< 0.01).Significance.This pilot study demonstrates that PAT may serve as a valuable surrogate marker for CI at the bedside, as a non-invasive and continuous modality in the PICU. The use of PAT in clinical practice remains to be thoroughly investigated.
