Dataset Information

Computational fluid dynamics investigation of the novel hybrid comprehensive stage II operation.

ABSTRACT:

Background

The hybrid comprehensive stage 2 (HCS2) procedure is a novel palliative operation applicable to a select subset of single ventricle patients with adequate native antegrade aortic flow to the upper body. Flow to the descending aorta, through the pulmonary outlet and ductal arch, is influenced by a stented intrapulmonary baffle connecting the branch pulmonary arteries. We used computational fluid dynamics (CFD) to elucidate the hemodynamic characteristics of this reconstruction.

Methods

We used multiscale CFD analysis of a synthetic, patient-derived HCS2 anatomic configuration with unsteady laminar flow conditions and a non-Newtonian blood model to quantify the resultant hemodynamics. The 3-dimensional CFD model was coupled to a 0-dimensional lumped parameter model of the peripheral circulation to determine the required boundary conditions.

Results

For the specific anatomy studied, the intrapulmonary baffle did not obstruct flow from the pulmonary trunk to ductal arch as long as the distance between the anterior pulmonary artery wall and baffle wall exceeded ∼7 mm. Vortex shedding off of the baffle wall did not develop, because of the short distance to the ductal arch. The stented baffle experienced significantly uneven "inward" loading from the systemic side. Pulmonary outlet flow separation distal to the baffle produced a low-speed recirculation region.

Conclusions

Hemodynamic patterns in this complex anatomy are generally favorable. Low flow recirculation could be mitigated by preoperative shape optimization. Calculated inward stresses on the pulmonary baffle can be used in the future to study baffle stent deformation, which is expected to be small.

SUBMITTER: Hameed M

PROVIDER: S-EPMC9390546 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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Publications

Computational fluid dynamics investigation of the novel hybrid comprehensive stage II operation.

Hameed Marwan M Prather Ray R Divo Eduardo E Kassab Alain A Nykanen David D Farias Michael M DeCampli William M WM

JTCVS open 20210427

<h4>Background</h4>The hybrid comprehensive stage 2 (HCS2) procedure is a novel palliative operation applicable to a select subset of single ventricle patients with adequate native antegrade aortic flow to the upper body. Flow to the descending aorta, through the pulmonary outlet and ductal arch, is influenced by a stented intrapulmonary baffle connecting the branch pulmonary arteries. We used computational fluid dynamics (CFD) to elucidate the hemodynamic characteristics of this reconstruction. ...[more]

PMID: 36003745

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Dataset Information

Computational fluid dynamics investigation of the novel hybrid comprehensive stage II operation.

Background

Methods

Results

Conclusions

Publications

Computational fluid dynamics investigation of the novel hybrid comprehensive stage II operation.

Similar Datasets

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