Dataset Information

Patient-Specific Multiscale Modeling of the Assisted Bidirectional Glenn.

ABSTRACT: BACKGROUND:First-stage palliation of neonates with single-ventricle physiology is associated with poor outcomes and challenging clinical management. Prior computational modeling and in vitro experiments introduced the assisted bidirectional Glenn (ABG), which increased pulmonary flow and oxygenation over the bidirectional Glenn (BDG) and the systemic-to-pulmonary shunt in idealized models. In this study, we demonstrate that the ABG achieves similar performance in patient-specific models and assess the influence of varying shunt geometry. METHODS:In a small cohort of single-ventricle prestage 2 patients, we constructed three-dimensional in silico models and tuned lumped parameter networks to match clinical measurements. Each model was modified to produce virtual BDG and ABG surgeries. We simulated the hemodynamics of the stage 1 procedure, BDG, and ABG by using multiscale computational modeling, coupling a finite-element flow solver to the lumped parameter network. Two levels of pulmonary vascular resistances (PVRs) were investigated: baseline (low) PVR of the patients and doubled (high) PVR. The shunt nozzle diameter, anastomosis location, and shape were also manipulated. RESULTS:The ABG increased the pulmonary flow rate and pressure by 15% to 20%, which was accompanied by a rise in superior vena caval pressure (2 to 3 mm Hg) at both PVR values. Pulmonary flow rate and superior vena caval pressures were most sensitive to the shunt nozzle diameter. CONCLUSIONS:Patient-specific ABG performance was similar to prior idealized simulations and experiments, with good performance at lower PVR values in the range of measured clinical data. Larger shunt outlet diameters and lower PVR led to improved ABG performance.

SUBMITTER: Shang JK

PROVIDER: S-EPMC6516076 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Patient-Specific Multiscale Modeling of the Assisted Bidirectional Glenn.

Shang Jessica K JK Esmaily Mahdi M Verma Aekaansh A Reinhartz Olaf O Figliola Richard S RS Hsia Tian-Yen TY Feinstein Jeffrey A JA Marsden Alison L AL

The Annals of thoracic surgery 20181122 4

<h4>Background</h4>First-stage palliation of neonates with single-ventricle physiology is associated with poor outcomes and challenging clinical management. Prior computational modeling and in vitro experiments introduced the assisted bidirectional Glenn (ABG), which increased pulmonary flow and oxygenation over the bidirectional Glenn (BDG) and the systemic-to-pulmonary shunt in idealized models. In this study, we demonstrate that the ABG achieves similar performance in patient-specific models ...[more]

PMID: 30471273

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Dataset Information

Patient-Specific Multiscale Modeling of the Assisted Bidirectional Glenn.

Publications

Patient-Specific Multiscale Modeling of the Assisted Bidirectional Glenn.

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