In Vivo Flow Dynamics of the Total Cavopulmonary Connection from Three-dimensional Multislice Magnetic Resonance ImagingAnnals of Thoracic Surgery
AbstractBackground. The total cavopulmonary connection (TCPC) design continues to be refined on the basis of flow analysis at the connection site. These refinements are of importance for myocardial energy conservation in the univentricular supported circulation. In vivo magnetic resonance phase contrast imaging provides semiquantitative flow visualization information. The purpose of this study was to understand the in vivo TCPC flow characteristics obtained by magnetic resonance phase contrast imaging and compare the results with our previous in vitro TCPC flow experiments in an effort to further refine TCPC surgical design. Methods. Twelve patients with TCPC underwent sedated three-dimensional, multislice magnetic resonance phase contrast imaging. Seven patients had intraatrial lateral tunnel TCPC and 5 had extracardiac TCPC. Results. In all patients in both groups a disordered flow pattern was observed in the inferior caval portion of the TCPC. Flow at the TCPC site appeared to be determined by connection geometry, being streamlined at the superior vena cava–pulmonary junction when the superior vena cava was offset and flared toward the left pulmonary artery. Without caval offset, intense swirling and dominance of superior vena caval flow was observed. In TCPC with bilateral superior vena cavae, the flow patterns observed included secondary vortices, a central stagnation point, and influx of the superior vena cava flow into the inferior caval conduit. A comparative analysis of in vivo flow and our previous in vitro flow data from glass model prototypes of TCPC demonstrated significant similarities in flow disturbances. Three-dimensional magnetic resonance phase contrast imaging in multiple coronal planes enabled a comprehensive semiquantitative flow analysis. The data are presented in traditional instantaneous images and in animated format for interactive display of the flow dynamics. Conclusions. Flow in the inferior caval portion of the TCPC is disordered, and the TCPC geometry determines flow characteristics.
Publisher's StatementNOTICE: this is the author’s version of a work that was accepted for publication in Annals of Thoracic Surgery. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Annals of Thoracic Surgery, 71, 3, (March 2001) DOI 10.1016/S0003-4975(00)02517-0
Citation InformationSharma S, Ensley AE, Hopkins K, Chatzimavroudis GP, Healy TM, Tam VKH, Kanter KR, Yoganathan AP. In vivo flow dynamics of the total cavopulmonary connection from three-dimensional multislice magnetic resonance imaging. Ann Thorac Surg. 2001;71:889-898.