During the Congress of the American Heart Association in New Orleans in november 2016 presented research physician Jouke Bokma results of an investigation by the international Indicator Registry. It is the largest international registration of patients with tetralogy of Fallot. Using MRI scans they looked at the results of this patient group. The research that Dr. Bokma presented focused on the effect and usefulness of the operative pulmonary-valve replacement in patients with this congenital heart disease. There was not a clearly improved prognosis after undergoing this operation, but there may be a selective group of patients who will benefit from it. The results of this research can help make the indication and timing of this operation. It is expected that the findings of this study shortly to be published in an international scientific journal.