BACKGROUND: In our multicenter study of the total cavopulmonary connection (TCPC), a cohort of patients with long-segment left pulmonary artery (LPA) stenosis was observed (35%). The clinically recognized detrimental effects of LPA stenosis motivated a computational fluid dynamic simulation study within 3-dimensional patient-specific and idealized TCPC pathways. The goal of this study was to quantify and evaluate the hemodynamic impact of LPA stenosis and to judge interventional strategies aimed at treating it. METHODS AND RESULTS: Simulations were conducted at equal vascular lung resistance, modeling both discrete stenosis (DS) and diffuse long-segment hypoplasia with varying degrees of obstruction (0% to 80%). Models having fenestrations of 2 to 6 mm and atrium pressures of 4 to 14 mm Hg were explored. A patient-specific, extracardiac TCPC with 85% DS was studied in its original configuration and after virtual surgery that dilated the LPA to 0% stenosis in the computer medium. Performance indices improved exponentially (R2>0.99) with decreasing obstruction. Diffuse long-segment hypoplasia was approximately 50% more severe with regard to lung perfusion and cardiac energy loss than DS. Virtual angioplasty performed on the 3-dimensional Fontan anatomy exhibiting an 85% DS stenosis produced a 61% increase in left lung perfusion and a 50% decrease in cardiac energy dissipation. After 4-mm fenestration, TCPC baffle pressure dropped by approximately 10% and left lung perfusion decreased by approximately 8% compared with the 80% DS case. CONCLUSIONS: DS <60% and diffuse long-segment hypoplasia <40% could be considered tolerable because both resulted in only a 12% decrease in left lung perfusion. In contrast to angioplasty, a fenestration (right-to-left shunt) reduced TCPC pressure at the cost of decreased left and right lung perfusion. These results suggest that pre-Fontan computational fluid dynamic simulation may be valuable for determining both the hemodynamic significance of LPA stenosis and the potential benefits of intervention.
BACKGROUND: In our multicenter study of the total cavopulmonary connection (TCPC), a cohort of patients with long-segment left pulmonary artery (LPA) stenosis was observed (35%). The clinically recognized detrimental effects of LPA stenosis motivated a computational fluid dynamic simulation study within 3-dimensional patient-specific and idealized TCPC pathways. The goal of this study was to quantify and evaluate the hemodynamic impact of LPA stenosis and to judge interventional strategies aimed at treating it. METHODS AND RESULTS: Simulations were conducted at equal vascular lung resistance, modeling both discrete stenosis (DS) and diffuse long-segment hypoplasia with varying degrees of obstruction (0% to 80%). Models having fenestrations of 2 to 6 mm and atrium pressures of 4 to 14 mm Hg were explored. A patient-specific, extracardiac TCPC with 85% DS was studied in its original configuration and after virtual surgery that dilated the LPA to 0% stenosis in the computer medium. Performance indices improved exponentially (R2>0.99) with decreasing obstruction. Diffuse long-segment hypoplasia was approximately 50% more severe with regard to lung perfusion and cardiac energy loss than DS. Virtual angioplasty performed on the 3-dimensional Fontan anatomy exhibiting an 85% DS stenosis produced a 61% increase in left lung perfusion and a 50% decrease in cardiac energy dissipation. After 4-mm fenestration, TCPC baffle pressure dropped by approximately 10% and left lung perfusion decreased by approximately 8% compared with the 80% DS case. CONCLUSIONS:DS <60% and diffuse long-segment hypoplasia <40% could be considered tolerable because both resulted in only a 12% decrease in left lung perfusion. In contrast to angioplasty, a fenestration (right-to-left shunt) reduced TCPC pressure at the cost of decreased left and right lung perfusion. These results suggest that pre-Fontan computational fluid dynamic simulation may be valuable for determining both the hemodynamic significance of LPA stenosis and the potential benefits of intervention.
Authors: Lakshmi P Dasi; Kartik S Sundareswaran; Colleen Sherwin; Diane de Zelicourt; Kirk Kanter; Mark A Fogel; Ajit P Yoganathan Journal: J Thorac Cardiovasc Surg Date: 2009-10-31 Impact factor: 5.209
Authors: David H Frakes; Kerem Pekkan; Lakshmi P Dasi; Hiroumi D Kitajima; Diane de Zelicourt; Hwa Liang Leo; Josie Carberry; Kartik Sundareswaran; Helene Simon; Ajit P Yoganathan Journal: Exp Fluids Date: 2008-12 Impact factor: 2.480
Authors: Christopher M Haggerty; Maria Restrepo; Elaine Tang; Diane A de Zélicourt; Kartik S Sundareswaran; Lucia Mirabella; James Bethel; Kevin K Whitehead; Mark A Fogel; Ajit P Yoganathan Journal: J Thorac Cardiovasc Surg Date: 2013-12-31 Impact factor: 5.209
Authors: Kerem Pekkan; Lakshimi P Dasi; Diane de Zélicourt; Kartik S Sundareswaran; Mark A Fogel; Kirk R Kanter; Ajit P Yoganathan Journal: Ann Biomed Eng Date: 2008-11-06 Impact factor: 3.934