4DFlow Magnetic Resonance Imaging in Patients With Pulmonary Hypertension Associated With Congenital Heart Disease

Congenital heart disease is the most common congenital anomaly. The life expectancy of children with congenital heart disease has increased considerably in recent years. Nevertheless, the evolution of these patients is marked by an increased risk of complications. Arrhythmias, heart failure, pulmonary arterial hypertension (PAH) and endocarditis may be promoted by the absence or delay of management in childhood, by residual lesions or post-operative cardiac scars and by the presence of prosthetic materials. PAH is a common complication of congenital heart disease, especially in non-operated shunts. PAH corresponds to an increase in pulmonary vascular resistance and mean pulmonary arterial pressure that becomes greater than 25mmHg at rest, leading to right ventricular failure and ultimately to the patient's death. Eisenmenger's syndrome corresponds to a non-reversible pulmonary arterial hypertension with a left-right shunt initially left open, then right-left secondary to the increase in pulmonary vascular resistance, leading to cyanosis, polycythemia and multivisceral involvement. It is the most advanced form of PAH with congenital heart disease. PAH will be suspected during echocardiographic follow-up of any patient with congenital heart disease, on the analysis of the velocity of tricuspid and/or pulmonary regurgitation flow. Echocardiography allows the monitoring of the VD (right ventricle) function, which is the major prognostic element in PAH. Cardiac catheterization is systematically recommended and remains the gold standard to confirm the diagnosis of PAH, establish its pathophysiology and prognosis but also for the follow-up under medical treatment of these patients in tertiary centres every 6 months. Although this tool is the gold standard, rigorously performed, it remains an invasive examination often poorly experienced by patients. 4D Flow MRI is a promising imaging that allows the acquisition of anatomical, volume, right ventricular remodeling and