Isolated aneurysmal dilatation of the right atrium, with surgical resolution, in a 53-year-old adult

Isolated aneurysmal dilatation of the right atrium is a rare congenital anomaly. Its identification occurs in several age groups, from the fetus to adulthood. The clinical manifestation of this anomaly varies according to the magnitude of the dilation, from asymptomatic patients, usually in children and young people, to the presence of difficult-to-control supraventricular arrhythmias, right heart failure, airway obstruction, pneumonia, and thromboembolic events in adults. The diagnosis is established after verification of cardiomegaly in routine radiographic examinations and confirmed later by echocardiogram. It is noteworthy in this pathology the disproportionate size of the right atrium concerning the other cardiac cavities, with the tricuspid ring also dilated but with a preserved tricuspid valve. The tricuspid insufficiency that accompanies the condition results from the dilation of the valve ring. The recommendation for surgical correction then becomes prophylactic in childhood, given the good evolution verified later. The differential diagnosis includes Ebstein's anomaly, pericardial effusion, and mediastinal thoracic tumors. Antiarrhythmic treatment and antithrombotic medication, represented by ASA, usually initiate clinical management, given the presence of supraventricular arrhythmias and cavitary thrombi, which are more commonly found in adulthood. The atrial resection surgery, initially conceived by Morrow and Behrendt in 1968, was oriented to symptomatic patients. These authors confirmed the good surgical result in a 23-year-old woman with atrial flutter and cardiomegaly, with an aneurysm of the right atrium. A good evolution was observed in this patient, in sinus rhythm and without symptoms after the correction. Since that beginning, surgical management has been advocated, having even extended to asymptomatic patients, as an elective and preventive procedure for known complications. Its diagnosis during fetal life has guided elective surgical management in the first years of life. The long evolution described in some non-operated cases, with 69 and 88 years of age, does not generally express benignity, as observed in this disease with many evolutionary complications. Few cases have been operated on in older adulthood, which motivated us to demonstrate in this report that a female patient was operated on at 53. (author)