Modeling Cardiovascular Rhythms

Application of signal processing methods to cardiovascular signals allows for investigation of novel statistical models of cardiovascular control, providing new quantitative indices that could have important implications for research studies of cardiovascular and autonomic regulation and for heart rate monitoring in clinical settings. We investigate multivariate models applied to cardiovascular variables, providing new insights into cardiovascular regulation. More recently, we have successfully derived new definitions of heart rate and heart rate variability based on point process Bayesian statistical models. Current research, funded by the National Heart Lung and Blood Institute (R01 Grant), applies these algorithms aiming at a more accurate, noninvasive assessment of cardiovascular control. Cardiovascular recordings are available through several collaborations. Data include tilt protocol studies, recordings under autonomic blockade, meditation studies, as well as sleep studies. Of late, the point process paradigm has been applied to data from subjects under nauseogenic stimuli and/or acupuncture, and correlated with simultaneous fMRI recordings. In yet another study, heart rate assessment has been correlated with several other physiological variables to predict apnea episodes in premature infants. Further studies have been initiated for assessment of depth of anesthesia using heart rate variability and galvanic skin response, of fetal heartbeat, and for automatic quantitative evaluation of human emotional states.


 Specific Projects


Point Process Models of Human Heart Beat Interval Dynamics     (Barbieri PI  NHLBI R01HL084502

The major goal of this project is to implement and validate a statistical point process model of cardiovascular control in order to provide new measures of heart rate and heart rate variability that could have important implications for research studies of cardiovascular and autonomic regulation and for heart rate monitoring in clinical settings.


Detection and Correction of Erroneous and Ectopic Heartbeats

A reliable, real-time classification and correction of ECG-derived heartbeats is a necessary prerequisite for an accurate online monitoring of HRV and cardiovascular control. We have developed a novel point-process-based method for real-time R-R interval error detection and correction. We present the algorithm in our IEEE TBME paper and we allow the research community to test and use our algorithm for free following this link.


Cardiovascular Control during Anesthesia

 In collaboration with Dr. Emery Brown and Dr. Patrick Purdon at the Dept of Anesthesia and Critical Care at MGH in Boston, heart rate variability analysis and cardiovascular modeling of autonomic control are applied to ECG, Respiration, and Skin Conductance from subjects under anesthesia, and correlated with simultaneous EEG recordings.


Cardiovascular Control during Acupuncture and Nausea

In collaboration with Dr. Vitaly Napadow at the Martinos Center in Boston, hear rate variability analysis and cardiovascular modeling of autonomic control are applied to data from subjects during nauseogenic stimulation while performing specific tasks or under acupuncture, and correlated with simultaneous fMRI recordings.


Automatic Quantitative Evaluation of Human Emotions

In collaboration with Dr. Maurizio Mauri at the IULM in Milano, Italy, this investigation is aimed at combining signal processing methods as applied to ECG, Respiration, EEG, and Skin Conductance in order to quantify specific human emotional states.


A computational tool based on heart beat dynamics to predict apnea episodes in premature infants

In collaboration with Dr. David Paydarfar at the University of Massachusetts in Worcester, heart rate variability and other physiological variables are combined in order to define predictors of apnea episodes and investigate if appropriately triggered vibro-tactile stimulation can help stabilize respiratory rhythm in premature infants.


Selected Publications

2010

Chen Z, Brown E, Barbieri R. Characterizing Nonlinear Heartbeat Dynamics within a Point Process Framework. IEEE Trans Biomed Eng. 2010 Jun;57(6):1335-47. Epub 2010 Feb 17. PubMed PMID: 20172783. PubMed Central PMCID: PMC2952361.

Wyller VB, Barbieri R, Saul JP. Blood pressure variability and closed-loop baroreflex assessment in adolescent chronic fatigue syndrome during supine rest and orthostatic stress. Eur J Appl Physiol. 2010 Oct 2. [Epub ahead of print]. PubMed PMID: 20890710.

Chen Z, Purdon PL, Harrell G, Pierce ET, Walsh J, Brown EN, Barbieri R. Dynamic Assessment of Baroreflex Control of Heart Rate During Induction of Propofol Anesthesia Using a Point Process Method. Ann Biomed Eng. 2010 Oct 13. [Epub ahead of print]. PubMed PMID: 20945159.

Chen Z, Purdon PL, Brown EN, Barbieri R. A Differential Autoregressive Modeling Approach within a Point Process Framework for Non-stationary Heartbeat Intervals Analysis. Conf Proc IEEE Eng Med Biol Soc. 2010; 978-1-4244-4124-2/10: 3567-3570. PubMed PMID: 21096829  

Mauri M, Magagnin V, Cipresso P, Mainardi L, Brown EN, Cerutti S, Villamira M, and Barbieri R. Psychophysiological Signals Associated with Affective States. Conf Proc IEEE Eng Med Biol Soc. 2010; 978-1-4244-4124-2/10: 3563-3566. PubMed PMID: 21096828. 

Kodituwakku S, Lazar SW, Indic P, Brown EN, Barbieri R. Point Process Time-frequency Analysis of Respiratory Sinus Arrhythmia under Altered Respiration Dynamics. Conf Proc IEEE Eng Med Biol Soc. 2010; 978-1-4244-4124-2/10: 1622-1625. PubMed PMID: 21096135.

Citi, L, Klerman, EB, Brown, EN, Barbieri, R. Point process heart rate variability assessment during sleep deprivation. Comput Cardiol. 2010 ;37.

Magagnin V, Mauri M, Cipresso P, Mainardi LT, Brown EN, Cerutti S, Villamira M, Barbieri R. Heart Rate Variability and Respiratory Sinus Arrhythmia Assessment of Affective States by Bivariate Autoregressive Spectral Analysis. Comput Cardiol. 2010 ;37.

2009

Chen Z, Brown E, Barbieri R. Assessment of Autonomic Control and Respiratory Sinus Arrhythmia Using Point Process Models of Human Heart Beat Dynamics. IEEE Trans Biomed Eng. 2009 Jul;56(7):1791-802. Epub 2009 Mar 4. PubMed PMID: 19272971. PubMed Central PMCID: PMC2804879.

Chen Z, Purdon PL, Pierce ET, Harrell PG, Brown EN, Barbieri R. Assessment of Baroreflex Control of Heart Rate During General Anesthesia Using a Point Process Method. Proc IEEE Int Conf Acoust Speech Signal Process. ICASSP 978-1-4244-2354-5/09: 333-336, 2009. PubMed PMID: 20473342. PubMed Central PMCID: PMC2867254.

Chen Z, Purdon PL, Pierce ET, Harrell PG, Walsh J, Salazar AF, Tavares CL, Brown EN,  Barbieri R. Linear and Nonlinear Quantification of Respiratory Sinus Arrhythmia during Propofol General Anesthesia. Conf Proc IEEE Eng Med Biol Soc. 2009; 978-1-4244-3296-7/09: 5336-5339. PubMed PMID: 19963899. PubMed Central PMCID: PMC2804255.

Chen Z, Putrino DF, Ba DE, Ghosh S, Barbieri R, Brown EN.  A Regularized Point Process Generalized Linear Model for Assessing the Functional Connectivity in the Cat Motor Cortex. Conf Proc IEEE Eng Med Biol Soc. 2009; 978-1-4244-3296-7/09: 5006-5009. PubMed PMID: 19965032. PubMed Central PMCID: PMC2822661.

LaCount L, Napadow V, Kuo B, Park K, Kim J, Brown EN, Barbieri R. Dynamic Cardiovagal Response to Motion Sickness: A Point-Process Heart Rate Variability Study. Comput Cardiol. 2009 Sep 13;36:49-52. PubMed PMID: 20445767. PubMed Central PMCID: PMC2863354.

2008

Barbieri R, Brown EN. Application of dynamic point process models to cardiovascular control. Biosystems. 2008 Jul-Aug;93(1-2):120-5. Epub 2008 Apr 26. PubMed PMID: 18515000; PubMed Central PMCID: PMC2561955.

Napadow V, Dhond R, Conti G, Makris N, Brown EN, Barbieri R. Brain correlates of autonomic modulation: combining heart rate variability with fMRI. Neuroimage. 2008 Aug 1;42(1):169-77. Epub 2008 Apr 30. PubMed PMID: 18524629; PubMed Central PMCID: PMC2603289.

Wyller VB, Barbieri R, Thaulow E, Saul JP.  Enhanced vagal withdrawal during mild orthostatic stress in adolescents with chronic fatigue. Ann Noninvasive Electrocardiol. 2008 Jan;13(1):67-73. PubMed PMID: 18234008.

Wyller VB, Saul JP, Barbieri R, de Lange C, Hopp E, Norum IB, Thaulow E. Autonomic heart rate control at rest and during unloading of the right ventricle in repaired tetralogy of Fallot in adolescents. Am J Cardiol. 2008 Oct 15;102(8):1085-9. Epub 2008 Jul 31. PubMed PMID: 18929714; PubMed Central PMCID: PMC2645862.

Chen Z, Brown EN, Barbieri R. Characterizing nonlinear heartbeat dynamics within a point process framework. Conf Proc IEEE Eng Med Biol Soc. 2008; 978-1-4244-1815-2/08: 2781-2784. PubMed PMID: 19163282. PubMed Central PMCID: PMC2644067.

Barbieri R, Chen Z, Brown EN. Assessment of Hippocampal and Autonomic Neural Activity by Point Process Models. Conf Proc IEEE Eng Med Biol Soc. 2008; 978-1-4244-1815-2/08: 3679. PubMed PMID: 19163509. PubMed Central PMCID: PMC2652877.

Chen Z, Brown EN, Barbieri R. A Study of Probabilistic Models for Characterizing Human Heart Beat Dynamics in Autonomic Blockade Control. Proc IEEE Int Conf Acoust Speech Signal Process ICASSP 1-4244-1484-9/08: 481-484, 2008 March 31.  PubMed PMID: 19593392. PubMed Central PMCID: PMC2707847.

Indic P, Salisbury EB, Paydarfar D, Brown EN, Barbieri R. Interaction between Heart Rate Variability and Respiration in Preterm Infants. Comput Cardiol. 2008 Sep14; 35; 57-60. PubMed PMID: 20333264. PubMed Central PMCID: PMC2843516.

Chen Z, Brown E, Barbieri R. A Point Process Approach to Assess Dynamic Baroreflex Gain. Comput Cardiol. 2008 Sep 14;35:805-808. PubMed PMID: 19756137. PubMed Central PMCID: PMC2676855.
2007
Barbieri R, Conti G, Dhond R, Brown EN, Napadow V. A combined fMRI and heart rate variability paradigm for assessment of central autonomic modulation. Conf Proc IEEE Eng Med Biol Soc.1-4244-0792-3/07:615-618, 2007.
2006

Barbieri R., Brown EN. Analysis of heart dynamics by point process adaptive filtering. IEEE Trans Biomed Eng. 2006 Jan;53(1):4-12. PubMed PMID:16402597.

Barbieri R, Brown EN. Correction of erroneous and ectopic beats using a point process adaptive algorithm. Conf Proc IEEE Eng Med Biol Soc. 2006;1:3373-6. PubMed PMID: 17945770.

Scotti S, Mauri M, Barbieri R, Jawad B, Mainardi L, Cerutti S, Brown EN. Automatic quantitative evaluation of emotions in E-learning applications. Conf Proc IEEE Eng Med Biol Soc. 2006;1:1359-62.  PubMed PMID: 17946457.

2005

Barbieri R, Matten EC, Alabi AA, Brown EN. A point process model of human heart rate intervals: new definitions of heart rate and heart rate variability. Am J Physiol Heart Circ Physiol. 2005 Jan;288(1):H424-35. Epub 2004 Sep 16.  PubMed PMID: 15374824.

Carrington MJ, Barbieri R, Colrain IM, Crowley KE, Kim Y, Trinder J. Changes in cardiovascular function during the sleep onset period in young adults.  J Appl Physiol. 2005 Feb;98(2):468-76. Epub 2004 Sep 24. PubMed PMID: 15448124.

2004

Barbieri R, Brown EN. A point process adaptive filter for time-variant analysis of heart rate variability. Conf Proc IEEE Eng Med Biol Soc. 2004;6:3941-4. PubMed PMID: 17271159.

Barbieri R, Frank LM, Nguyen DP, Quirk MC, Solo V, Wilson MA, Brown EN. A Bayesian decoding algorithm for analysis of information encoding in neural ensembles. Conf Proc IEEE Eng Med Biol Soc. 2004;6:4483-6. PubMed PMID: 17271302.

2002

Barbieri R, Triedman JK, Saul JP. Heart rate control and mechanical cardiopulmonary coupling to assess central volume: a systems analysis. Am J Physiol Regul Integr Comp Physiol. 2002 Nov;283(5):R1210-20. PubMed PMID: 12376415.

2001

Barbieri R, Parati G, Saul JP. Closed vs. open loop assessment of the heart rate baroreflex. IEEE Eng Med Biol Mag. 2001 Mar-Apr;20(2):33-42. PubMed PMID: 11321718.

1999
Barbieri R, Saul JP. Autoregressive modeling for assessing closed-loop feedback and feedforward in the arterial baroreflex. Methodology and Clinical Applications of Blood Pressure. M. Di Rienzo et al. (eds). IOS Press, pp. 21-34, 1999.
1997

Barbieri R, Di Virgilio V, Cerutti S, Saul JP. Multivariate time-variant autoregressive techniques for closed-loop cardiovascular control using simulations and comparisons. Frontiers of Blood Pressure and Heart Rate Analysis. M. Di Rienzo et al. (eds). IOS Press; pp. 101-114, 1997

Barbieri R, Bianchi AM, Triedman JK, Mainardi LT, Cerutti S, Saul JP. Model dependency of multivariate autoregressive spectral analysis: quantifying cardiovascular control using bivariate and trivariate models. IEEE Eng Med Biol Mag. 1997 Sep-Oct;16(5):74-85. PubMed PMID: 9313084.

Di Virgilio V, Barbieri R, Mainardi LT, Strano S, Cerutti S. A multivariate time-variant AR method for the analysis of heart rate and arterial blood pressure. Med Eng Phys. 1997 Mar;19(2):109-24. PubMed PMID: 9203145.

Mainardi LT, Bianchi AM, Furlan R, Piazza S, Barbieri R, Di Virgilio V, Malliani A, Cerutti S. Multivariate time-variant identification of cardiovascular variability signals: a beat-to-beat spectral parameter estimation in vasovagal syncope. IEEE Trans Biomed Eng. 1997 Oct;44(10):978-89. PubMed PMID: 9311167.

1996

Barbieri R, Waldmann RA, Di Virgilio V, Triedman JK, Bianchi AM, Cerutti S, Saul JP. Continuous quantification of baroreflex and respiratory control of heart rate by use of bivariate autoregressive techniques. Annals of Noninvasive Electrocardiology; 3:264-77, 1996.

Risk MR, Sobh JF, Barbieri R, Armentano RL, Ramirez AJ, Saul JP. Variabilidad de las señales cardiorespiratorias, Parte 1: variabilidad a corto plazo. Revista Argentina de Bioingenieria, 1996.

Risk MR, Sobh JF, Barbieri R, Armentano RL, Ramirez AJ, Saul JP. Variabilidad de las señales cardiorespiratorias, Parte 2: variabilidad a largo plazo. Revista Argentina de Bioingenieria, 1996.

Barbieri R, Triedman JK, Di Virgilio V, Cerutti S, Saul JP. Arterial pressure control during non-hypo/hypertensive changes in central venous volume: assessment with multivariate autoregressive modeling. IEEE 0276-6547/94, 85-88, Computers in Cardiology, Indianapolis, IN, 1996.

Barbieri R, Waldmann RA, Di Virgilio V, Triedman JK, Bianchi AM, Cerutti S, Saul JP. Continuous quantification of baroreflex and respiratory control of heart rate by use of bivariate autoregressive techniques. Annals of Noninvasive Electrocardiology, 3: 264-77, 1996.