Imposition of Fontan physiology: Effects on strain and global measures of ventricular function

Abstract Objective We sought to evaluate contractile function in single ventricle patients before and after imposition of Fontan physiology. Methods Single right (SRV) (n=38) and single left ventricles (SLV) (n=11) underwent cardiac magnetic resonance imaging (CMR) pre and post Fontan operation. Global radial (GRS), circumferential (GCS), and longitudinal strains (GLS) were measured along with ejection fraction (EF) and atrioventricular valve regurgitation (AVVR). Results Age at pre Fontan CMR was 3.1±1.3 years and post Fontan was 5.8±2.7 years. There were no significant EF differences between SRV and SLV both pre and post Fontan, and EF did not deteriorate significantly after Fontan. SRV-GRS were significantly lower than SLV-GRS both pre (24.3 vs. 32.1%, p=0.048) and post (21.8 vs. 29.7%, p=0.045) Fontan. Both GRS and GCS of SRV deteriorated significantly after Fontan (GRS; p=0.01 and GCS; p=0.009). Strains showed positive correlations pre and post Fontan with positive correlations among each strain. Within all patients, strains correlated positively with EF. Strains and EF negatively correlated with AVVR (GRS; p=0.03, r=-0.22, GCS; p=0.03, r=-0.23, EF; p Conclusions SRV strains are lower than SLV’s both pre and post Fontan and deteriorates after the Fontan operation. Our study suggests that strain measures may detect ventricular deterioration earlier than EF. As strains pre and post Fontan were positively correlated, and negatively correlated with AVVR, the early institution of myocardial protective therapy including AVVR management, especially for SRV patients, may have benefit.