Two-Dimensional Strain Echocardiographic Parameters and Clinical Outcomes Associated with Significant Atrioventricular Regurgitation in a Single-Center Adult Fontan Population.

Background: Significant atrioventricular valve regurgitation (AVVR) is prevalent in Fontan adults. Two-dimensional speckle-tracking echocardiography allows for evaluation of subclinical myocardial dysfunction and offers technical benefits. We aimed to evaluate the association of AVVR with echocardiographic parameters and adverse outcomes.

Materials and methods: Fontan adults (≥18 years) with lateral tunnel or extracardiac connection actively followed at our institution were retrospectively reviewed. Patients with AVVR on most recent transthoracic echocardiogram (≥grade 2 as per American Society of Echocardiography guidelines) were matched with Fontan controls. Echocardiographic parameters, including global longitudinal strain (GLS), were measured. The composite outcome of Fontan failure included Fontan conversion, protein losing enteropathy, plastic bronchitis, and New York Heart Association Class III/IV.

Results: Sixteen patients (14%, mean age 28.4 ± 7.0 years) with predominantly moderate AVVR (81%) were identified. The mean duration of AVVR was 8.1 ± 5.8 months. There was no significant reduction in ejection fraction (EF) (51.2% ± 11.7% vs. 54.7% ± 10.9%, P = 0.39) or GLS (-16.0% ± 5.2% vs. -16.0% ± 3.5%, P = 0.98) associated with AVVR. Larger atrial volumes and longer deceleration time (DT) were observed in the AVVR group. Patients with AVVR and a worse GLS (≥-16%) had higher E velocity, DT, and medial E/E' ratio. The incidence of Fontan failure did not differ from controls (38% vs. 25%, P = 0.45). Patients with worse GLS (≥-16%) demonstrated a marked trend toward a higher incidence of Fontan failure (67% vs. 20%, P = 0.09).

Conclusions: In Fontan adults, a short duration of AVVR did not influence EF or GLS but was associated with larger atrial volumes and those with worse GLS demonstrated some differences in diastolic parameters. Larger multicenter studies throughout its disease course are warranted.