Aneurysms of the sinus of Valsalva (SV) and the atrial septum are a rare association. We report the case of a 28-year-old woman, who was admitted to our department complaining of progressive dyspnea of 10 days of evolution, five hours previous to her admission to the hospital; she presented sudden oppressive anterior chest pain, accompanied by palpitations. The presence of rupture of the right SV to the right atrium was clinically confirmed, by echocardiography and hemodynamic studies. In addition, an associated atrial septal aneurysm was found. She underwent surgical correction through sinusplasty without requiring aortic valve replacement. The patient presented persistent postoperative atrioventricular block, which required a permanent pacemaker. Clinical evolution was satisfactory. To our knowledge, this case is a rare combination of two isolated malformations, without previous events that could explain the rupture of the right SV.