RAF-1 Mutation Associated with a Risk for Ventricular Arrhythmias in a Child with Noonan Syndrome and Cardiovascular Pathology

Introduction: Noonan syndrome (NS) is a dominant autosomal disease, caused by mutations in genes involved in cell differentiation, growth and senescence, one of them being RAF1 mutation. Congenital heart disease may influence the prognosis of the disease.
Case presentation: We report a case of an 18 month-old female patient who presented to our institute at the age of 2 months when she was diagnosed with obstructive hypertrophic cardiomyopathy, pulmonary infundibular and pulmonary valve stenosis, a small atrial septal defect and extrasystolic arrhythmia. She was born from healthy parents, a non-consanguineous marriage. Due to suggestive phenotype for NS molecular genetic testing for RASopathies was performed in a center abroad, establishing the presence of RAF-1 mutation. Following rapid progression of cardiac abnormalities, the surgical correction was performed at 14 months of age. In the early postoperative period, the patient developed episodes of sustained ventricular tachycardia with hemodynamic instability, for which associated treatment was instituted with successful conversion to sinus rhythm. At 3-month follow-up, the patient was hemodynamically stable in sinus rhythm.
Conclusions: The presented case report certifies the importance of recognizing the genetic mutation in patients with NS, which allows predicting the severity of cardiac abnormalities and therefore establishing a proper therapeutic management of these patients.