Asynchrony in Operated Tetralogy of Fallot (FALLOT-XI)

Exploring Asynchronism in Operated Fallot Tetralogy : A Comparative Study of Electrical and Mechanical Activation of the Right Ventricle by Three-Dimensional Analysis

The objective of this work is to estimate the correlation between the electrical activation of the VD measured by the CARTO electrophysiological mapping system and the mechanical activation of the VD measured by 3D echocardiography and 3D speckle-tracking. Our hypothesis is that there is a strong correlation between electrical activation and mechanical activation in patients with an operated Fallot tetralogy.

Fallot tetralogy is the most common cyanogenic congenital heart disease. Thanks to advances in surgery, most patients survive to adulthood but develop a failure of the function of the right ventricle and then of the left ventricle resulting in progressive heart failure and death of patients. Despite corrective surgeries in adulthood, including pulmonary valve surgery, heart failure remains a major problem. One of the mechanisms of this heart failure is the right intraventtricular asynchronism associated with the postoperative right branch block, which will secondaryly become complicated from an interventricular asynchronism for left intraventtricular, partly explaining the overall progressive failure of cardiac function. To date, there is no model for combining a combined analysis of electrical and mechanical activation in the same patients. Understanding these mechanisms would allow us to better understand the pathophysiology of heart failure in this population and to propose targeted therapies to prevent this asynchronism by adapting surgical techniques, or treating this asynchronism with electrical therapy such as bivascular resynchronization. Each patient in each group will perform, according to standard practice, an electrophysiological exploration with mapping of the heart using the CARTO system, a cardiac MRI and a 3-dimensional transthoracic echocardiography. The follow-up of each patient takes place during a scheduled hospitalization as part of the care. Their participation in the study only lasts for the duration of the hospitalization.

Comparison of electrical and mechanical activation by computational morphometry with temporal recalling to define electromechanical activation maps in healthy subjects and patients with Fallot tetralogy operated.

Global 3D VD longitudinal strain in %, Global 3D VD circumferential strain in %, Mean deformation pattern, Mean RV right ventricle shape, RV Average Curvature Index.

3D VD Ejection Fraction and End-Diastolic and End-Systolic Volume 3D VD; 3D right ventricle volume data processed by Tomtec 4D RV Function 2.0.

Area strain 3D in %, Longitudinal strain in %, Circumferential strain in %, Global 3D at right ventricle level.

Area strain 3D in %, Longitudinal strain in %, Circumferential strain in %, Global 3D at right ventricle level.

Right and Left Ventricular MRI Volumetry; Pulmonary flow by MRI. T1 spontaneous (ms) and extracellular volume fraction (%) by MRI MRI scar area

Comparison of electrical activation maps based on anatomical data, including diffuse fibrosis and scars in Fallot subjects

Inclusion Criteria: Inclusion Criteria in the Fallot group Male or female patient aged 18, Patient with Fallot Tetralogy operated. nclusion Criteria in the Control group Male or female patient aged 18, Patient benefiting from electrophysiological exploration for a healthy heart arrhythmia, Patient with a significant lack of heart disease. Exclusion Criteria: Exclusion Criteria in the Fallot group Patient with associated left heart disease, Patient with an acoustic window that does not allow for proper echocardiography, Patient with contraindication to MRI, Woman of childbearing age without effective contraception (HAS criteria) or Pregnant (ßHCG > 20 IU/l) or nursing woman. Exclusion Criteria in the Control group Patient with an acoustic window that does not allow proper echocardiography, Patient with MRI contraindication, Woman of childbearing age without effective contraception (HAS criteria) or Pregnant (ßHCG > 20 IU/l) or nursing woman, Cardiac pathology detected during echocardiography.