References of "Kolh, Philippe"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailA multi-scale cardiovascular system model can account for the load-dependence of the end-systolic pressure-volume relationship.
Pironet, Antoine ULg; Desaive, Thomas ULg; Kosta, Sarah ULg et al

in BioMedical Engineering OnLine (2013), 12(1), 8

ABSTRACT: BACKGROUND: The end-systolic pressure-volume relationship is often considered as a load-independent property of the heart and, for this reason, is widely used as an index of ventricular ... [more ▼]

ABSTRACT: BACKGROUND: The end-systolic pressure-volume relationship is often considered as a load-independent property of the heart and, for this reason, is widely used as an index of ventricular contractility. However, many criticisms have been expressed against this index and the underlying time-varying elastance theory: first, it does not consider the phenomena underlying contraction and second, the end-systolic pressure volume relationship has been experimentally shown to be load-dependent. METHODS: In place of the time-varying elastance theory, a microscopic model of sarcomere contraction is used to infer the pressure generated by the contraction of the left ventricle, considered as a spherical assembling of sarcomere units. The left ventricle model is inserted into a closed-loop model of the cardiovascular system. Finally, parameters of the modified cardiovascular system model are identified to reproduce the hemodynamics of a normal dog. RESULTS: Experiments that have proven the limitations of the time-varying elastance theory are reproduced with our model: (1) preload reductions, (2) afterload increases, (3) the same experiments with increased ventricular contractility, (4) isovolumic contractions and (5) flow-clamps. All experiments simulated with the model generate different end-systolic pressure-volume relationships, showing that this relationship is actually load-dependent. Furthermore, we show that the results of our simulations are in good agreement with experiments. CONCLUSIONS: We implemented a multi-scale model of the cardiovascular system, in which ventricular contraction is described by a detailed sarcomere model. Using this model, we successfully reproduced a number of experiments that have shown the failing points of the time-varying elastance theory. In particular, the developed multi-scale model of the cardiovascular system can capture the load-dependence of the end-systolic pressure-volume relationship. [less ▲]

Detailed reference viewed: 60 (44 ULg)
Full Text
Peer Reviewed
See detailEnregistrement des données infirmières : exploitation des données et intégration dans le financement des soins infirmiers
THONON, Olivier ULg; LEROY, Stéphanie ULg; MACLOT, Eric ULg et al

in Actes de la 6ème conférence francophone en Gestion et Ingénierie des SystèmEs Hospitaliers - GISEH (2012, September)

Detailed reference viewed: 9 (2 ULg)
Full Text
Peer Reviewed
See detailStructural model of the mitral valve included in a cardiovascular closed loop model. Static and dynamic validation
Paeme, Sabine ULg; Pironet, Antoine ULg; Chase, J. Geoffrey et al

in proceedings of 8th IFAC Symposium on Biological and Medical Systems, Budapest 29-31 août 2012 (2012, August 31)

Detailed reference viewed: 23 (4 ULg)
Full Text
Peer Reviewed
See detailAnimal Models of Mitral Regurgitation Induced by Mitral Valve Chordae Tendineae Rupture.
Leroux, Aurélia ULg; Moonen, Marie ULg; Pierard, Luc ULg et al

in Journal of Heart Valve Disease (The) (2012), 21

Background – Mitral regurgitation (MR) is a common valvular disease throughout the world. Various diagnostic techniques have been developed to assess the causes and severity of MR, and the therapeutic ... [more ▼]

Background – Mitral regurgitation (MR) is a common valvular disease throughout the world. Various diagnostic techniques have been developed to assess the causes and severity of MR, and the therapeutic approaches to this disease have been widely documented. However, treatments for chronic MR remain controversial, and various animal models of chronic MR (including chordae tendineae rupture, rapid pacing and ischemia) have been developed to study the pathophysiology and therapeutic approaches to this disease. The objective of this paper is to review the animal MR models that have been developed using a mitral valve chordae tendineae rupture technique. Animal models – Dogs and sheep have been the animals most commonly used in MR models induced by mitral valve chordae tendineae rupture, mainly due to considerations of cardiac size. Chordae tendineae cutting is performed using closed or open chest techniques. In the closed chest model, long flexible grasping forceps are positioned percutaneously in order to tear the mitral valve chordae. In the open chest model, cardiopulmonary bypass is performed and either selected chordae are cut under direct visualization, or a non specified number of chordae are cut using a metal device inserted through the left ventricular apex. Whatever the model used, MR has been found to become chronic 3 to 6 months after the induction of MR by chordae rupture. The reported mortality and complication rates of these models are high. Conclusion – In the long term, experimental evolution of chronic MR is similar to the evolution occurring naturally in patients suffering from chronic MR. These models could thus be useful in understanding the disease better and in testing new therapeutic modalities. This review summarizes the physiological effects of each of these techniques and compares the advantages and disadvantages of each procedure. [less ▲]

Detailed reference viewed: 39 (12 ULg)
Full Text
Peer Reviewed
See detailBeat-to-beat estimation of the continuous left and right cardiac elastance from metrics commonly available in clinical settings.
Stevenson, David; Revie, James; Chase, J. Geoffrey et al

in BioMedical Engineering OnLine (2012), 11(1), 73

ABSTRACT: INTRODUCTION: : Functional time-varying cardiac elastances (FTVE) contain a rich amount of information about the specific cardiac state of a patient. However, a FTVE waveform is very invasive to ... [more ▼]

ABSTRACT: INTRODUCTION: : Functional time-varying cardiac elastances (FTVE) contain a rich amount of information about the specific cardiac state of a patient. However, a FTVE waveform is very invasive to directly measure, and is thus currently not used in clinical practice. This paper presents a method for the estimation of a patient specific FTVE, using only metrics that are currently available in a clinical setting. METHOD: : Correlations are defined between invasively measured FTVE waveforms and the aortic and pulmonary artery pressures from 2 cohorts of porcine subjects, 1 induced with pulmonary embolism, the other with septic shock. These correlations are then used to estimate the FTVE waveform based on the individual aortic and pulmonary artery pressure waveforms, using the "other" dysfunction's correlations as a cross validation. RESULTS: : The cross validation resulted in 1.26% and 2.51% median errors for the left and right FTVE respectively on pulmonary embolism, while the septic shock cohort had 2.54% and 2.90% median errors. CONCLUSIONS: : The presented method accurately and reliably estimated a patient specific FTVE, with no added risk to the patient. The cross validation shows that the method is not dependent on dysfunction and thus has the potential for generalisation beyond pulmonary embolism and septic shock. [less ▲]

Detailed reference viewed: 27 (6 ULg)
Full Text
Peer Reviewed
See detailAlgorithmic Processing of Pressure Waveforms to FacilitateEstimation of Cardiac Elastance
Stevenson, D.; Revie, J.; Chase, J. G. et al

in BioMedical Engineering OnLine (2012), 11

Introduction: Cardiac elastances are highly invasive to measure directly, but are clinically useful due tothe amount of information embedded in them. Information about the cardiac elastance, which can be ... [more ▼]

Introduction: Cardiac elastances are highly invasive to measure directly, but are clinically useful due tothe amount of information embedded in them. Information about the cardiac elastance, which can be used toestimate it, can be found in the downstream pressure waveforms of aortic pressure (Pao) and the pulmonaryartery (Ppa). However these pressure waveforms are typically noisy and biased, and require processing in orderto locate the specific information required for the cardiac elastance estimation. This paper presents the methodto algorithmically process the pressure waveforms. Methods: A shear transform is developed in order to helplocate information in the pressure waveforms. This transform turns difficult to locate corners into easy to locatemaximum or minimum points as well as providing error correction. Results: The method located all points 87out of 88 waveforms for Ppa to within the sampling frequency. For Pao, out of 616 total points, 605 were foundwithin 1%, 5 within 5%, 4 within 10% and 2 within 20%. Conclusions: The presented method provides arobust, accurate and dysfunction independent way to locate points on the aortic and pulmonary artery pressurewaveforms, allowing the non-invasive estimation of the left and right cardiac elastance. [less ▲]

Detailed reference viewed: 33 (4 ULg)
Full Text
Peer Reviewed
See detailComputer-based monitoring of global cardiovascular dynamics during acute pulmonary embolism and septic shock in swine
Revie, JA; Stevenson, D; Chase, JG et al

in Critical Care (2012), 16 (Suppl 1)

Detailed reference viewed: 15 (3 ULg)
Full Text
See detailOpportunité des séjours : l’outil AEP dans les hôpitaux belges
FONTAINE, Pierre; GILLAIN, Daniel ULg; THONON, Olivier ULg et al

in Gestions Hospitalieres (2012)

L'évolution des coûts de santé en général, et hospitaliers en particulier, a conduit les autorités belges à prendre des mesures pour limiter les durées de séjour. Les hôpitaux étant à présent financés en ... [more ▼]

L'évolution des coûts de santé en général, et hospitaliers en particulier, a conduit les autorités belges à prendre des mesures pour limiter les durées de séjour. Les hôpitaux étant à présent financés en fonction du nombre d'admissions et des pathologies correspondantes, l'usage d'un outil permettant d'estimer la proportion des admissions et des journées inappropriées, ainsi que leurs causes, est d'un intérêt majeur. Trois enquêtes transversales successives ont été menées de 2003 à 2005 dans 23 hôpitaux aigus en médecine interne, chirurgie et gériatrie. En tout, 12 000 séjours et 1 800 admissions ont ainsi été audités au moyen de l'Appropriateness Evaluation Protocol. [less ▲]

Detailed reference viewed: 14 (5 ULg)
Full Text
Peer Reviewed
See detailAcute abdominal aortic aneurysm: significant regional differences across Norway.
Kolh, Philippe ULg

in European journal of vascular and endovascular surgery : the official journal of the European Society for Vascular Surgery (2012), 44(3), 273

Detailed reference viewed: 30 (2 ULg)
Full Text
Peer Reviewed
See detailStrengths and limits of risk stratification models in vascular surgery.
Kolh, Philippe ULg

in European journal of vascular and endovascular surgery : the official journal of the European Society for Vascular Surgery (2012), 44(1), 62-3

Detailed reference viewed: 12 (1 ULg)
Full Text
Peer Reviewed
See detailThe new 2011 ACCF/AHA Guidelines on Coronary Artery Bypass Grafting Surgery: are they different from the 2010 ESC/EACTS Guidelines on Myocardial Revascularisation?
Kolh, Philippe ULg; Sousa Uva, Miguel; Wijns, William

in EuroIntervention : Journal of EuroPCR in Collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology (2012), 8(1), 33-4

Detailed reference viewed: 5 (2 ULg)
Full Text
Peer Reviewed
See detailGuidelines on the management of valvular heart disease (version 2012): the Joint Task Force on the Management of Valvular Heart Disease of the European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS).
Vahanian, Alec; Alfieri, Ottavio; Andreotti, Felicita et al

in European journal of cardio-thoracic surgery : official journal of the European Association for Cardio-thoracic Surgery (2012), 42(4), 1-44

Detailed reference viewed: 24 (5 ULg)
Full Text
Peer Reviewed
See detailRetrospective medical record evaluation: reliability in assessing causation, preventability, and disability of adverse events.
Verelst, Sandra; JACQUES, Jessica ULg; Van den Heede, Koen et al

in International Journal of Health Care Quality Assurance (2012), 25(8), 649-62

PURPOSE: The purpose of this article is to assess the reliability of an in-depth analysis on causation, preventability, and disability by two separate review teams on five selected adverse events in acute ... [more ▼]

PURPOSE: The purpose of this article is to assess the reliability of an in-depth analysis on causation, preventability, and disability by two separate review teams on five selected adverse events in acute hospitals: pressure ulcer, postoperative pulmonary embolism or deep vein thrombosis, postoperative sepsis, ventilator-associated pneumonia and postoperative wound infection. DESIGN/METHODOLOGY/APPROACH: The analysis uses a retrospective medical record review of 1,515 patient records by two independent teams in eight acute Belgian hospitals for the year 2005. The Mann-Whitney U-test is used to identify significant differences between the two review teams regarding occurrence of adverse events as well as regarding the degree of causation, preventability, and disability of found adverse events. FINDINGS: Team 1 stated a high probability for health care management causation in 95.5 per cent of adverse events in contrast to 38.9 per cent by Team 2. Likewise, high preventability was considered in 83.1 per cent of cases by Team 1 versus 51.7 per cent by Team 2. Significant differences in degree of disability between the two teams were also found for pressure ulcers, postoperative pulmonary embolism or deep vein thrombosis and postoperative wound infection, but not for postoperative sepsis and ventilator-associated pneumonia. ORIGINALITY/VALUE: New insight on the degree of and reasons for the huge differences in adverse event evaluation is provided. [less ▲]

Detailed reference viewed: 17 (2 ULg)
Full Text
Peer Reviewed
See detailESC Guidelines for the management of acute myocardial infarction in patients presenting with ST-segment elevation.
Steg, Ph Gabriel; James, Stefan K.; Atar, Dan et al

in European Heart Journal (2012), 33(20), 2569-619

Detailed reference viewed: 21 (4 ULg)
Full Text
Peer Reviewed
See detailEstimating afterload, systemic vascular resistance and pulmonary vascular resistance in an intensive care setting
Stevenson, D; Revie, J.; Chase, JG et al

in Proceedings of BMS2012 (2012)

Detailed reference viewed: 16 (0 ULg)
Full Text
Peer Reviewed
See detailCardiovascular modelling and the Intensive Care Unit clinician
Desaive, Thomas ULg; LAMBERMONT, Bernard ULg; Kolh, Philippe ULg et al

in Proceedings of BMS 2012 (2012)

Detailed reference viewed: 18 (2 ULg)