Influence of Respiration on Collateral Flow in the Fontan Population Using Real-time Phase-contrast Cardiovascular Magnetic Resonance: Collateral Flow Does Not Protect the Ventricle From Volume Deficiency and Diastolic Dysfunction.

Purpose: The clinical significance of collateral flow for the ventricular function of patients with univentricular hearts is often debated. This study evaluates the impact of collateral flow on respiration-dependent preload modification and diastolic function in Fontan patients assessed by systemic and pulmonary vein (PV) flow patterns.

Materials And Methods: Real-time phase-contrast cardiovascular magnetic resonance was performed in the right upper PV, ascending aorta, superior, and inferior vena cava (IVC) in 21 Fontan patients and 11 healthy individuals.