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Helbing W.a. - One of the best experts on this subject based on the ideXlab platform.

  • Usefulness of cardiac magnetic resonance imaging combined with low-dose dobutamine stress to detect an abnormal ventricular stress response in children and young adults after fontan operation at young age.
    'Elsevier BV', 2008
    Co-Authors: Robbers-visser D., Harkel, D.j. Ten, Kapusta L., Strengers J.l., Dalinghaus M., Meijboom F.j., Pattynama P.m., Bogers A.j., Helbing W.a.
    Abstract:

    After Fontan operation, patients are limited in increasing cardiac output and in exercise capacity. This has been related to impaired preload or other factors leading to decreased global ventricular performance with stress. To study these factors, the stress responses of functionally univentricular hearts were assessed at rest and during low-dose dobutamine stress using cardiovascular magnetic resonance imaging. Thirty-two patients after Fontan completion at young age were included (27 with total cavopulmonary Connection, 5 with Atriopulmonary Connection; mean age 13.3 years, range 7.5 to 22.2; 23 male patients; median follow-up after Fontan operation 8.1 years, range 5.2 to 17.8). A multiphase short-axis stack of 10 to 12 contiguous slices of the systemic ventricle was obtained at rest and during low-dose dobutamine stress cardiovascular magnetic resonance imaging (maximum 7.5 microg/kg/min). With stress-testing, heart rate, ejection fraction, and cardiac index increased adequately (p

  • Usefulness of cardiac magnetic resonance imaging combined with low-dose dobutamine stress to detect an abnormal ventricular stress response in children and young adults after fontan operation at young age.
    'Elsevier BV', 2008
    Co-Authors: Robbers-visser D., Harkel, D.j. Ten, Kapusta L., Strengers J.l., Dalinghaus M., Meijboom F.j., Pattynama P.m., Bogers A.j., Helbing W.a.
    Abstract:

    Contains fulltext : 69461.pdf (publisher's version ) (Closed access)After Fontan operation, patients are limited in increasing cardiac output and in exercise capacity. This has been related to impaired preload or other factors leading to decreased global ventricular performance with stress. To study these factors, the stress responses of functionally univentricular hearts were assessed at rest and during low-dose dobutamine stress using cardiovascular magnetic resonance imaging. Thirty-two patients after Fontan completion at young age were included (27 with total cavopulmonary Connection, 5 with Atriopulmonary Connection; mean age 13.3 years, range 7.5 to 22.2; 23 male patients; median follow-up after Fontan operation 8.1 years, range 5.2 to 17.8). A multiphase short-axis stack of 10 to 12 contiguous slices of the systemic ventricle was obtained at rest and during low-dose dobutamine stress cardiovascular magnetic resonance imaging (maximum 7.5 microg/kg/min). With stress-testing, heart rate, ejection fraction, and cardiac index increased adequately (p

Christian P Brizard - One of the best experts on this subject based on the ideXlab platform.

  • total cavopulmonary Connection is superior to Atriopulmonary Connection fontan in preventing thrombus formation computer simulation of flow related blood coagulation
    Pediatric Cardiology, 2015
    Co-Authors: Koichi Sughimoto, Fuyou Liang, Hao Liu, Kazuki Okauchi, Diana Zannino, Christian P Brizard, Michiko Sugawara, Kenichi Tsubota
    Abstract:

    The classical Fontan route, namely the Atriopulmonary Connection (APC), continues to be associated with a risk of thrombus formation in the atrium. A conversion to a total cavopulmonary Connection (TCPC) from the APC can ameliorate hemodynamics for the failed Fontan; however, the impact of these surgical operations on thrombus formation remains elusive. This study elucidates the underlying mechanism of thrombus formation in the Fontan route by using a two-dimensional computer hemodynamic simulation based on a simple blood coagulation rule. Hemodynamics in the Fontan route was simulated with Navier-Stokes equations. The blood coagulation and the hemodynamics were combined using a particle method. Three models were created: APC with a square atrium, APC with a round atrium, and TCPC. To examine the effects of the venous blood flow velocity, the velocity at rest and during exercise (0.5 and 1.0 W/kg) was measured. The total area of the thrombi increased over time. The APC square model showed the highest incidence for thrombus formation, followed by the APC round, whereas no thrombus was formed in the TCPC model. Slower blood flow at rest was associated with a higher incidence of thrombus formation. The TCPC was superior to the classical APC in terms of preventing thrombus formation, due to significant blood flow stagnation in the atrium of the APC. Thus, local hemodynamic behavior associated with the complex channel geometry plays a major role in thrombus formation in the Fontan route.

  • the fontan procedure contemporary techniques have improved long term outcomes
    Circulation, 2007
    Co-Authors: Yves Dudekem, Ajay J Iyengar, Andrew D Cochrane, Leeanne Grigg, J Ramsay, Gavin R Wheaton, Daniel J Penny, Christian P Brizard
    Abstract:

    Background— To determine whether patients undergoing the lateral tunnel and extracardiac conduit modifications of the Fontan procedure have better outcomes than patients undergoing a classical Atriopulmonary Connection. Methods and Results— Between 1980 and 2000, 305 consecutive patients underwent a Fontan procedure at our institution. There were 10 hospital deaths (mortality: 3%) with no death after 1990. Independent risk factors for mortality were preoperative elevated pulmonary artery pressures ( P =0.002) and common atrioventricular valve ( P =0.04). Fontan was taken down during hospital stay in 7 patients. A mean of 12±6 years of follow-up was obtained in the 257 nonforeign Fontan survivors. Completeness of concurrent follow-up was 96%. Twenty-year survival was 84% (95% CI: 79 to 89%). Recent techniques improved late survival. The 15-year survival after Atriopulmonary Connection was 81% (95% CI: 73% to 87%) versus 94% (95% CI: 79% to 98%) for lateral tunnel ( P =0.004). Nine pts required heart transplantation (8 Atriopulmonary Connection, 1 lateral tunnel). Undergoing a Fontan modification independently predicted decreased occurrence of arrhythmia, and 15-year freedom from SVT was 61% (95% CI: 51% to 70%) for Atriopulmonary Connection versus 87% (95% CI: 76% to 93%) for lateral tunnel ( P =0.02). Freedom from Fontan failure (death, take-down, transplantation, or NYHA class III-IV) was 70% (95% CI: 58% to 79%) at 20 years. After extra-cardiac conduits, no death, SVT, or failure was observed. Conclusions— The Fontan procedure remains a palliation, but outcomes of patients have improved. Better patient selection minimizes hospital mortality. Patients with lateral tunnel and extracardiac conduit modifications experience less arrhythmia and are likely to have failure of their Fontan circulation postponed.

Robbers-visser D. - One of the best experts on this subject based on the ideXlab platform.

  • Usefulness of cardiac magnetic resonance imaging combined with low-dose dobutamine stress to detect an abnormal ventricular stress response in children and young adults after fontan operation at young age.
    'Elsevier BV', 2008
    Co-Authors: Robbers-visser D., Harkel, D.j. Ten, Kapusta L., Strengers J.l., Dalinghaus M., Meijboom F.j., Pattynama P.m., Bogers A.j., Helbing W.a.
    Abstract:

    After Fontan operation, patients are limited in increasing cardiac output and in exercise capacity. This has been related to impaired preload or other factors leading to decreased global ventricular performance with stress. To study these factors, the stress responses of functionally univentricular hearts were assessed at rest and during low-dose dobutamine stress using cardiovascular magnetic resonance imaging. Thirty-two patients after Fontan completion at young age were included (27 with total cavopulmonary Connection, 5 with Atriopulmonary Connection; mean age 13.3 years, range 7.5 to 22.2; 23 male patients; median follow-up after Fontan operation 8.1 years, range 5.2 to 17.8). A multiphase short-axis stack of 10 to 12 contiguous slices of the systemic ventricle was obtained at rest and during low-dose dobutamine stress cardiovascular magnetic resonance imaging (maximum 7.5 microg/kg/min). With stress-testing, heart rate, ejection fraction, and cardiac index increased adequately (p

  • Usefulness of cardiac magnetic resonance imaging combined with low-dose dobutamine stress to detect an abnormal ventricular stress response in children and young adults after fontan operation at young age.
    'Elsevier BV', 2008
    Co-Authors: Robbers-visser D., Harkel, D.j. Ten, Kapusta L., Strengers J.l., Dalinghaus M., Meijboom F.j., Pattynama P.m., Bogers A.j., Helbing W.a.
    Abstract:

    Contains fulltext : 69461.pdf (publisher's version ) (Closed access)After Fontan operation, patients are limited in increasing cardiac output and in exercise capacity. This has been related to impaired preload or other factors leading to decreased global ventricular performance with stress. To study these factors, the stress responses of functionally univentricular hearts were assessed at rest and during low-dose dobutamine stress using cardiovascular magnetic resonance imaging. Thirty-two patients after Fontan completion at young age were included (27 with total cavopulmonary Connection, 5 with Atriopulmonary Connection; mean age 13.3 years, range 7.5 to 22.2; 23 male patients; median follow-up after Fontan operation 8.1 years, range 5.2 to 17.8). A multiphase short-axis stack of 10 to 12 contiguous slices of the systemic ventricle was obtained at rest and during low-dose dobutamine stress cardiovascular magnetic resonance imaging (maximum 7.5 microg/kg/min). With stress-testing, heart rate, ejection fraction, and cardiac index increased adequately (p

William J Brawn - One of the best experts on this subject based on the ideXlab platform.

  • factors influencing early and late outcome following the fontan procedure in the current era the two commandments
    European Journal of Cardio-Thoracic Surgery, 2007
    Co-Authors: Riad B M Hosein, Andrew J B Clarke, Simon P Mcguirk, Massimo Griselli, Oliver Stumper, Joseph V De Giovanni, David J Barron, William J Brawn
    Abstract:

    Objective: This study was undertaken to identify the factors affecting early and late outcome following the Fontan procedure in the current era. We have examined whether conventional selection criteria, the ‘Ten Commandments’, are still applicable in the current era. Materials and methods: Between January 1988 and July 2004, 406 patients underwent a modified Fontan procedure at a median age of 4.7 years (IQR, 3.8—7.1 years). The single functional ventricle was of left (n = 241, 59%) or right ventricular morphology (n = 163, 40%). The modified Fontan procedure was performed using an Atriopulmonary Connection (n = 162, 40%) or total cavopulmonary Connection (TCPC) involving a lateral atrial tunnel (n = 50, 12%) or extracardiac conduit (n = 194, 48%). They were fenestrated in 216 patients (53%). Results: The early mortality was 4.4% (n = 18) and four other patients required takedown of the Fontan circulation. On multivariable analysis, early outcome was adversely influenced by two factors (p < 0.05): preoperative impaired ventricular function and elevated pulmonary artery pressures. Two risk models were constructed for early outcome based on preoperative and predictable operative variables (Model 1) and all preoperative and operative data (Model 2). Both models were calibrated across all deciles (p = 0.83, p = 0.25) and discriminated well. The area under the ROC curve was 0.85 and 0.89, respectively. There were 21 late deaths, 1 patient required late takedown of the Fontan circulation and 3 required orthotopic cardiac transplantation. Actuarial survival was 90 � 2%, 86 � 2% and 82 � 3% at 5, 10 and 15 years, respectively. Multivariable analysis identified that outcome was influenced by preoperatively impaired ventricular function, elevated preoperative pulmonary artery pressures and an earlier year of operation. The freedom from reintervention was 83 � 4%, 76 � 4% and 74 � 8% at 5, 10 and 15 years, respectively. Additional risk factors for reintervention were right atrial isomerism and preoperative small pulmonary artery size. Conclusions: Late outcome of the Fontan circulation is encouraging. Ventricular morphology, surgical technique and fenestration do not appear to influence early or late outcome. Preoperatively impaired ventricularfunction and elevated pulmonaryartery pressures have an adverse influenceon both early and late outcome. Reintervention is common, with small preoperative pulmonary artery size being an additional risk factor. # 2007 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

Strengers J.l. - One of the best experts on this subject based on the ideXlab platform.

  • Usefulness of cardiac magnetic resonance imaging combined with low-dose dobutamine stress to detect an abnormal ventricular stress response in children and young adults after fontan operation at young age.
    'Elsevier BV', 2008
    Co-Authors: Robbers-visser D., Harkel, D.j. Ten, Kapusta L., Strengers J.l., Dalinghaus M., Meijboom F.j., Pattynama P.m., Bogers A.j., Helbing W.a.
    Abstract:

    After Fontan operation, patients are limited in increasing cardiac output and in exercise capacity. This has been related to impaired preload or other factors leading to decreased global ventricular performance with stress. To study these factors, the stress responses of functionally univentricular hearts were assessed at rest and during low-dose dobutamine stress using cardiovascular magnetic resonance imaging. Thirty-two patients after Fontan completion at young age were included (27 with total cavopulmonary Connection, 5 with Atriopulmonary Connection; mean age 13.3 years, range 7.5 to 22.2; 23 male patients; median follow-up after Fontan operation 8.1 years, range 5.2 to 17.8). A multiphase short-axis stack of 10 to 12 contiguous slices of the systemic ventricle was obtained at rest and during low-dose dobutamine stress cardiovascular magnetic resonance imaging (maximum 7.5 microg/kg/min). With stress-testing, heart rate, ejection fraction, and cardiac index increased adequately (p

  • Usefulness of cardiac magnetic resonance imaging combined with low-dose dobutamine stress to detect an abnormal ventricular stress response in children and young adults after fontan operation at young age.
    'Elsevier BV', 2008
    Co-Authors: Robbers-visser D., Harkel, D.j. Ten, Kapusta L., Strengers J.l., Dalinghaus M., Meijboom F.j., Pattynama P.m., Bogers A.j., Helbing W.a.
    Abstract:

    Contains fulltext : 69461.pdf (publisher's version ) (Closed access)After Fontan operation, patients are limited in increasing cardiac output and in exercise capacity. This has been related to impaired preload or other factors leading to decreased global ventricular performance with stress. To study these factors, the stress responses of functionally univentricular hearts were assessed at rest and during low-dose dobutamine stress using cardiovascular magnetic resonance imaging. Thirty-two patients after Fontan completion at young age were included (27 with total cavopulmonary Connection, 5 with Atriopulmonary Connection; mean age 13.3 years, range 7.5 to 22.2; 23 male patients; median follow-up after Fontan operation 8.1 years, range 5.2 to 17.8). A multiphase short-axis stack of 10 to 12 contiguous slices of the systemic ventricle was obtained at rest and during low-dose dobutamine stress cardiovascular magnetic resonance imaging (maximum 7.5 microg/kg/min). With stress-testing, heart rate, ejection fraction, and cardiac index increased adequately (p