Abstract 2118: Patients With Fontan and Superior Cavopulmonary Connections Have Higher Systemic to Pulmonary Collateral Flow Than Two Ventricle Controls
Background: Systemic to pulmonary collateral flow (SPCF) is common in single ventricle patients. We recently demonstrated a method of quantifying collateral flow using phase contrast magnetic resonance velocity mapping (PC-MRI). We utilized this method to examine the differences in collateral flow between pts with superior cavopulmonary connections (SCPC), total cavopulmonary connections (TCPC), and controls.
Methods and Results: We measured Ao, SVC, IVC, right (RPA) and left (LPA) PA, left (LPV), and right (RPV) PV flows in 35 single ventricle patients, (27 SCPC and 8 TCPC) and 16 controls, during routine studies using through-plane PC-MRI. Two independent measures of SPCF were obtained:
Ao − (SVC + IVC)
(LPV-LPA) + (RPV-RPA).
Values were normalized to BSA, Ao, and PV and comparisons made using regression and Student t-test. Level of significance was considered 0.05. The results are summarized in the table⇓. The indexed SPCF, percent aortic flow and percent pulmonary flow in both SCPC and TCPC pts were significantly greater than controls. SCPC pts had significantly higher SPCF than TCPC pts. SCPC or TCPC type, history of a Blalock-Taussig shunt, and presence of PA stenosis were not related to amount of collateral flow. In SCPC pts, the collateral flow is significantly positively correlated with time from SCPC. In TPCP pts, the collateral flow trends toward a negative correlation with time from TCPC, but did not reach significance.
Conclusions: Both SCPC and TCPC pts demonstrate significant systemic to pulmonary collateral flow, with SCPC pts having significantly higher SPCF than TCPC pts.