The following is a summary of “Utility of novel STE parameters in echocardiographic assessment of single ventricle after Fontan palliation,” published in the June 2024 issue of Cardiology by Kowalczyk et al.

A functionally single ventricle (FSV) includes congenital heart defects that can’t be fixed with typical biventricular surgery. The Fontan operation is the go-to treatment for most patients with FSV. 

Researchers conducted a prospective study assessing the efficacy of speckle tracking echocardiography (STE) parameters, measured both at rest and during exercise, work for assessing univentricular hearts. 

They enrolled 37 patients with a single ventricle post-fontan operation, hospitalized (2019-2021). Echocardiographic stress tests were conducted in the labs, and the study was conducted using a semi-recumbent bicycle ergometer. The STE measured longitudinal strains of the FSV free wall (Ɛ) and of myocardial layers, subendocardial, medial, and subepicardial. A transmural longitudinal strain gradient (TG) was calculated as the difference between the longitudinal deformation of subendocardial and subepicardial layers. Cardiac magnetic resonance imaging (CMR), cardio-pulmonary test (CPET) results, demographics, past treatments, and comorbidities were also included. 

The results showed that Ɛ at rest and during exercise showed no correlation with CPET physical capacity or CMR results. However, the transmural strain gradient was linked to physical performance parameters- peak oxygen uptake- and related to the FSV ejection fraction measured by MRI.

Investigators concluded that measuring TG and FSV free wall strain is helpful in assessing single ventricle function. The measures were positively linked to peak oxygen uptake and ejection fraction, especially in patients undergoing fontan procedure.

Source: internationaljournalofcardiology.com/article/S0167-5273(24)00908-2/fulltext