Cardiac features
Both FMD2 patients had a persistent ductus arteriosus, which was part of a more complex cardiac defect (ventricular septal defect, pulmonary atresia, bicuspid aortic valve with mild stenosis, progressive aortic root dilatation (> 3 –z-score), persistent left superior vena cava draining into the coronary sinus and ectopic atrial tachycardia) in the patient born at 35 weeks of gestation with the recurrent P485L variant. The congenital heart defect in this patient was a major reason for failure to thrive and recurrent admissions in her early months of life.