A long-term mechanical cavopulmonary support device for patients with Fontan circulation.

In patients with a single ventricle, failure of the cardiovascular system may be prevented by substituting the missing sub-pulmonary ventricle with a pump. The aim of this study was to design and evaluate a device for long-term cavopulmonary support. A radial pump with two inlets and two outlets, a single impeller, mechanical bearings, and dual motor configuration was developed. Motor and fluid dynamic components were designed and simulated using computational methods including thermal effects. Hydraulic properties were determined in-vitro with 3D-printed prototypes. The pump design was virtually implanted in an MRI-derived total cavopulmonary connection (TCPC). Computational fluid dynamics (CFD) showed flow fields without regions of flow stagnation (velocity < 0.1 m/s) and only minor recirculations within the pump between 2-10 L/min against pressure heads of 0-50 mmHg at 2500-5000 rpm. The computed maximum temperature increase of blood due to motor heat was 1.3 K. Virtual implantation studies showed that the pump would introduce an additional volume of approximately 4 mL. Experimentally determined hydraulic performance results agreed well with CFD (deviation of <1.3 mmHg) and indicated pressure-sensitive characteristics (∼-2.6 mmHg/(L/min)) while balancing the two inlet pressures (∆P < 2.5 mmHg) under imbalanced inflow conditions. Through in-silico and in-vitro investigations, we demonstrated a promising pump design, which fulfills the basic requirements for long-term cavopulmonary support.

[1]  C. Brizard,et al.  The Fontan Procedure: Contemporary Techniques Have Improved Long-Term Outcomes , 2007, Circulation.

[2]  Steven Deutsch,et al.  Correlation of In Vivo Clot Deposition With the Flow Characteristics in the 50 cc Penn State Artificial Heart: A Preliminary Study , 2004, ASAIO journal.

[3]  Jack Rychik,et al.  The failing Fontan: etiology, diagnosis and management , 2011, Expert review of cardiovascular therapy.

[4]  O. Reinhartz,et al.  Challenges in Longer-Term Mechanical Support of Fontan Circulation in Sheep , 2012, ASAIO journal.

[5]  R. Ohye,et al.  Berlin heart ventricular assist device as a long‐term bridge to transplantation in a Fontan patient with failing single ventricle , 2015, Pediatric transplantation.

[6]  Dhyaa H Kafagy,et al.  Physics-driven impeller designs for a novel intravascular blood pump for patients with congenital heart disease. , 2016, Medical engineering & physics.

[7]  James W Long,et al.  Two‐Year Outcomes with a Magnetically Levitated Cardiac Pump in Heart Failure , 2018, The New England journal of medicine.

[8]  Gregory A. Ewald,et al.  A Fully Magnetically Levitated Circulatory Pump for Advanced Heart Failure , 2017, The New England journal of medicine.

[9]  H. Laks,et al.  Novel techniques of mechanical circulatory support for the right heart and Fontan circulation. , 2014, International journal of cardiology.

[10]  J. Gangemi,et al.  A Viable Therapeutic Option: Mechanical Circulatory Support of the Failing Fontan Physiology , 2013, Pediatric Cardiology.

[11]  M. Genoni,et al.  Right-sided univentricular cardiac assistance in a failing Fontan circulation. , 2008, The Annals of thoracic surgery.

[12]  U. Kertzscher,et al.  A Two-stage Rotary Blood Pump Design with Potentially Lower Blood Trauma: A Computational Study , 2016, The International journal of artificial organs.

[13]  Jeffrey A. Jones,et al.  Pulmonary arteriovenous malformations after the superior cavopulmonary shunt: mechanisms and clinical implications , 2014, Expert review of cardiovascular therapy.

[14]  Klaus Affeld,et al.  Numerical estimation of blood damage in artificial organs. , 2004, Artificial organs.

[15]  J. Galati,et al.  Redefining Expectations of Long-Term Survival After the Fontan Procedure: Twenty-Five Years of Follow-Up From the Entire Population of Australia and New Zealand , 2014, Circulation.

[16]  Guruprasad A Giridharan,et al.  Cavopulmonary assist: (em)powering the univentricular fontan circulation. , 2011, Seminars in thoracic and cardiovascular surgery. Pediatric cardiac surgery annual.

[17]  Mauro Grigioni,et al.  Mechanically Assisted Total Cavopulmonary Connection With an Axial Flow Pump: Computational and In Vivo Study. , 2016, Artificial organs.

[18]  D. Farrar,et al.  Low Bearing Wear in Explanted HeartMate II Left Ventricular Assist Devices After Chronic Clinical Support , 2013, ASAIO journal.

[19]  P. Ewert,et al.  Caval flow reflects Fontan hemodynamics: quantification by magnetic resonance imaging , 2012, Clinical Research in Cardiology.

[20]  Marc Gewillig,et al.  The Fontan circulation after 45 years: update in physiology , 2016, Heart.

[21]  Daniel Timms,et al.  A review of clinical ventricular assist devices. , 2011, Medical engineering & physics.

[22]  Patricia Friedmann,et al.  The use of the Berlin Heart EXCOR in patients with functional single ventricle. , 2014, The Journal of thoracic and cardiovascular surgery.

[23]  Fang Yang,et al.  High-speed visualization of disturbed pathlines in axial flow ventricular assist device under pulsatile conditions. , 2015, The Journal of thoracic and cardiovascular surgery.

[24]  Jianguo Zhu,et al.  Thermal Analysis of High-Speed SMC Motor Based on Thermal Network and 3-D FEA With Rotational Core Loss Included , 2009, IEEE Transactions on Magnetics.

[25]  A.C. Koenig,et al.  Calculation of eddy current losses in conductive sleeves of synchronous machines , 2008, 2008 18th International Conference on Electrical Machines.

[26]  Mirko Meboldt,et al.  Hydraulic Characterization of Implantable Rotary Blood Pumps , 2019, IEEE Transactions on Biomedical Engineering.

[27]  M. Slepian,et al.  Thrombus Formation Patterns in the HeartMate II Ventricular Assist Device: Clinical Observations Can Be Predicted by Numerical Simulations , 2014, ASAIO journal.

[28]  Katharine H Fraser,et al.  The use of computational fluid dynamics in the development of ventricular assist devices. , 2011, Medical engineering & physics.

[29]  M. Gewillig.  THE FONTAN CIRCULATION , 2005, Heart.

[30]  Volkmar Falk,et al.  2016 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure , 2016, Revista espanola de cardiologia.

[31]  A. Yoganathan,et al.  Geometric characterization of patient-specific total cavopulmonary connections and its relationship to hemodynamics. , 2014, JACC. Cardiovascular imaging.

[32]  C. Daniels,et al.  Fontan Liver Disease: Review of an Emerging Epidemic and Management Options , 2015, Current Treatment Options in Cardiovascular Medicine.

[33]  M. Gewillig,et al.  Failure of the fontan circulation. , 2014, Heart failure clinics.

[34]  Patrick W O'Leary,et al.  Long-term results of the Fontan operation for double-inlet left ventricle. , 2005, The American journal of cardiology.

[35]  Mirko Meboldt,et al.  Cavopulmonary mechanical circulatory support in Fontan patients and the need for physiologic control: A computational study with a closed-loop exercise model , 2018, The International journal of artificial organs.

[36]  K. Lomas,et al.  A computer model of human thermoregulation for a wide range of environmental conditions: the passive system. , 1999, Journal of applied physiology.

[37]  Klaus Affeld,et al.  Numerical Analysis of Blood Damage Potential of the HeartMate II and HeartWare HVAD Rotary Blood Pumps. , 2015, Artificial organs.

[38]  J. Kirklin,et al.  Challenges of Cardiac Transplantation Following the Fontan Procedure , 2017, World journal for pediatric & congenital heart surgery.

[39]  John K. Triedman,et al.  Long-Term Survival, Modes of Death, and Predictors of Mortality in Patients With Fontan Surgery , 2008, Circulation.

[40]  Raymond K. Newswanger,et al.  Chronic In Vivo Test of a Right Heart Replacement Blood Pump for Failed Fontan Circulation. , 2019, ASAIO journal.

[41]  Choon-Sik Jhun,et al.  Fontan Circulatory Assist Device , 2015 .

[42]  D. Driscoll,et al.  40-Year Follow-Up After the Fontan Operation: Long-Term Outcomes of 1,052 Patients. , 2015, Journal of the American College of Cardiology.

[43]  S. Yazaki,et al.  Haemodynamic characteristics before and after the onset of protein losing enteropathy in patients after the Fontan operation. , 2013, European journal of cardio-thoracic surgery : official journal of the European Association for Cardio-thoracic Surgery.

[44]  J. Triedman,et al.  Trends in Congenital Heart Disease: The Next Decade , 2016, Circulation.

[45]  Patrick W. O'Leary,et al.  Prevalence, clinical presentation and natural history of patients with single ventricle , 2002 .

[46]  Amy L Throckmorton,et al.  Intravascular mechanical cavopulmonary assistance for patients with failing Fontan physiology. , 2009, Artificial organs.

[47]  Christopher M Haggerty,et al.  Experimental and numeric investigation of Impella pumps as cavopulmonary assistance for a failing Fontan. , 2012, The Journal of thoracic and cardiovascular surgery.

[48]  C. Yerebakan,et al.  Urgent implantation of the Berlin Heart Excor biventricular assist device as a total artificial heart in a patient with single ventricle circulation. , 2014, Journal of Thoracic and Cardiovascular Surgery.

[49]  S. Colan,et al.  Longitudinal Outcomes of Patients With Single Ventricle After the Fontan Procedure. , 2017, Journal of the American College of Cardiology.

[50]  Jun Chen,et al.  Performance evaluation of a pediatric viscous impeller pump for Fontan cavopulmonary assist. , 2013, The Journal of thoracic and cardiovascular surgery.

[51]  Brandon W. Coats,et al.  Cavopulmonary assist for the univentricular Fontan circulation: von Kármán viscous impeller pump. , 2010, The Journal of thoracic and cardiovascular surgery.