Author/Authors :
Koçyıldırım, Ergin University of Pittsburgh - Children’s Hospital of Pittsburgh,McGowan Institute of Regenerative Medicine - Department of Cardiothoracic Surgery, USA , Dur, Onur Carnegie Mellon University - Biomedical Engineering Department, USA , Soran, Özlem University of Pittsburgh - Cardiovascular Institute, USA , Tüzün, Egemen Texas A M University - Texas A M Institute of Preclinical Studies, College Station, USA , Miller, Matthew W. Texas A M University - Texas A M Institute of Preclinical Studies, College Station, USA , Housler, Greggory J. University of Pittsburgh - McGowan Institute of Regenerative Medicine, USA , Wearden, Peter D. University of Pittsburgh - McGowan Institute of Regenerative Medicine,Children’s Hospital of Pittsburgh - Department of Cardiothoracic Surgery, USA , Fossum, Theresa W. Texas A M University - Texas A M Institute of Preclinical Studies,College Station, USA , Morell, Victor O. University of Pittsburgh - Children’s Hospital of Pittsburgh - Department of Cardiothoracic Surgery, USA , Pekkan, Kerem Carnegie Mellon University - Biomedical Engineering Department, USA
Abstract :
Objective: Functionally univentricular heart (FUH) anomalies are the leading cause of death from all structural birth defects. Total cavopulmonary connection (TCPC) is the last stage of the palliative surgical reconstruction with significant late hemodynamic complications requiring high-risk heart transplantation. Alternative therapeutic options for these critically ill patients are crucial. In Phase I, we investigated the effect of pulsatility of venous flow (VF) waveform on the performance of functional and “failing” Fontan (FF) patients based on conduit power loss. In phase 2, the effect of enhanced external counter pulsation on Fontan circulation flow rates is monitored. Methods: In phase 1, Doppler VFs were acquired from FF patients with ventricle dysfunction. Using computational fluid dynamics (CFD), hemodynamic efficiencies of the FF, functional and in-vitro generated mechanically assisted VF waveforms were evaluated. In phase 2, Fontan circulation on sheep model was created and enhanced external counter pulsation (EECP) applied. Results: Variations in the pulsatile content of the VF waveforms altered conduit efficiency notably. High frequency and low amplitude oscillations lowered the pulsatile component of power losses in FF VF waveforms. The systemic venous flow, pulmonary artery and aorta flows increased by utilizing EECP. Conclusion: Our data highlighted the significance of VF pulsatility on energy efficiency inside SV circulation and the feasibility of VF waveform optimization. EECP assist in Fontan circulation can result in venous flow augmentation.
Keywords :
Fontan , Fontan circulation , failing Fontan circulation , enhanced external counterpulsation , animal experiment , content of the VF waveforms
