Title

Computational Analysis of Hybrid Norwood Circulation With Distal Aortic Arch Obstruction and Reverse Blalock-Taussig Shunt

Authors

Authors

A. Ceballos; I. R. Argueta-Morales; E. Divo; R. Osorio; C. A. Caldarone; A. J. Kassab;W. M. DeCampli

Comments

Authors: contact us about adding a copy of your work at STARS@ucf.edu

Abbreviated Journal Title

Ann. Thorac. Surg.

Keywords

LEFT-HEART SYNDROME; SHEAR-STRESS; VENTRICLE; PALLIATION; PULMONARY; COMPARE; Cardiac & Cardiovascular Systems; Respiratory System; Surgery

Abstract

Background. The hemodynamics characteristics of the hybrid Norwood (HN) procedure differ from those of the conventional Norwood and are not fully understood. We present a multiscale model of HN circulation to understand local hemodynamics and effects of aortic arch stenosis and a reverse Blalock-Taussig shunt (RBTS) on coronary and carotid perfusion. Methods. Four 3-dimensional models of four HN anatomic variants were developed, with and without 90% distal preductal arch stenosis and with and without a 4-mm RBTS. A lumped parameter model of the circulation was coupled to a local 3-dimensional computational fluid dynamics model. Outputs from the lumped parameter model provided waveform boundary conditions for the computational fluid dynamics model. Results. A 90% distal arch stenosis reduced pressure and net flow-rate through the coronary and carotid arteries by 30%. Addition of the RBTS completely restored pressure and flow rate to baseline in these vessels. Zones of flow stagnation, flow reversal, and recirculation in the presence of stenosis were rendered more orderly by addition of the RBTS. In the absence of stenosis, presence of the shunt resulted in extensive zones of disturbed flow within the RBTS and arch. Conclusions. We found that a 4-mm x 21-mm RBTS completely compensated for the effects of a 90% discrete stenosis of the distal aortic arch in the HN. Placed preventatively, the RBTS and arch displayed zones with thrombogenic potential showing recirculation and stagnation that persist for a substantial fraction of the cardiac cycle, indicating that anticoagulation should be considered with a prophylactic RBTS. (Ann Thorac Surg 2012;94:1540-50) (C) 2012 by The Society of Thoracic Surgeons

Journal Title

Annals of Thoracic Surgery

Volume

94

Issue/Number

5

Publication Date

1-1-2012

Document Type

Article

Language

English

First Page

1540

Last Page

1550

WOS Identifier

WOS:000310439700033

ISSN

0003-4975

Share

COinS