Use of echocardiographic parameters of longitudinal mechanics to estimate diastolic function of systemic ventricle in patients after fontan operation

Abstract

Objective. To study the possibilities of using echocardiographic parameters of longitudinal mechanics to assess the diastolic function of the systemic ventricle (SV) in patients after Fontan operation.
 Material and methods. We examined 29 children aged 8,6 3,16 years with a functionally single ventricle of the heart after performing a total cavopulmonary connection with fenestration of extracardiac conduit. By computed tomography there were evaluated: myocardial mass index (MMI) SV, ejection fraction (EF) SV, cardiac output (CO) SV, cardiac index (CI) SV. In addition to conventional echocardiographic (Echo) parameters, we also studied: diastolic velocity parameters of the longitudinal mechanics of the SV during the early rapid filling phase (SR E), in the phase of late diastolic filling (SR A), the ratio of the peaks of the strain rate (SR E/SR A), the stiffness index of a functionally single atrium, the atrial strain in conduit phase (AS cd), reservoir (ASr), and in the contractile phase (AS ct).
 Results. Reduced values of the SI, CO and CI SV, an increase in MMI SV, normal values of EF SV. The parameters of the longitudinal diastolic strain rate in the early and late filling phases of e SV showed a direct significant correlation with SI, CO and CI SV and inverse correlation with E/e '. Parameters of longitudinal strain of the functionally single atrium in all phases were reduced, they all correlated with E / e, SR E / SR A, MMI SV, SI, CO and CI SV. There was no statistically significant relationship between the parameters of the longitudinal function of the atrium in all phases and atrial stiffness with sex and body surface area.
 Conclusions. 1. The parameters of the longitudinal diastolic strain rate can be used to identify the diastolic dysfunction of the systemic ventricle in children after Fontan operation. 2. The hemodynamic parameters of the systemic ventricle (stroke index, cardiac output, cardiac index) determine the parameters of its diastolic mechanics. 3. The reservoir, conduit, and contractile atrial function in patients after total cavopulmonary connection are associated with both characteristics of diastolic longitudinal strain rate and hemodynamic parameters of systemic ventricle.