Idiopathic aneurysmal giant right atrial enlargement with thrombus formation

Abstract

A 12-year-old boy presented to our outpatient department with progressive dyspnoea and palpitations of 6-month duration. Cardiovascular system examination revealed a short ejection systolic murmur at the left lateral heart border. Chest X-ray showed gross cardiomegaly. Two-dimensional ECHO revealed massive aneurysmal right atrial (RA) enlargement, low-pressure tricuspid regurgitation and dysplastic tricuspid valve with compression of the left atrium (LA) and left ventricle (LV). Cardiac CT showed grossly enlarged RA compressing the LA, LV, right pulmonary artery and right upper lobe pulmonary vein. Initially, the patient refused surgery. On follow-up, a thrombus was seen in the giant RA and the patient agreed to and underwent successful surgery. Absence of pericardium was specifically excluded on cardiac MRI and on surgery. Resected atrial tissue showed wall thinning and focal fibrosis establishing idiopathic dilation of the RA. The patient is on regular follow-up.

Idiopathic dilatation of the right atrium: a not so benign entity

“…Some authors report non-specific findings such as tiny atrial tissue, as well as nonspecific muscular changes such as elongation of the fibres, lipomatous degeneration, lymphocytic infiltration, and patch fibrosis. 17,18,23 The finding of inflammatory tissue in some samples suggested myocarditis as a possible cause, 1 although this was only detected in isolated cases. In our series, the patient in whom we performed a histopathological study showed non-specific elements, which, consistent with the literature, did not prove useful.…”

“…[11][12][13][14][15][16][17] Treatment is controversial in asymptomatic patients, especially in children. Prophylactic antiplatelet treatment has been suggested to prevent the risk of thrombus formation, 18 and surgical reduction has been performed in some symptomatic patients or in asymptomatic patients at high risk of progression, including initial severe right atrial dilatation, significant enlargement over a short period, compression of adjacent structures, or uncontrolled arrhythmias. 7 We present four cases of foetal diagnosis of idiopathic dilatation of the right atrium and discuss management from foetal to early postnatal life and follow-up until the patients reached the age of 5 to 6 years.…”

Giant Right Atrial Aneurysm: Antenatal Diagnosis and Surgical Treatment

“…1 Such aneurysms are rare, with their natural history complicated by death, heart failure, arrhythmias, and thrombosis. 2,3 Sporadic cases have been reported for all ages, from newborns to patients aged 75 years. 2 Diagnosis during childhood is quite rare, and prenatal diagnosis even rarer.…”

Idiopathic congenital right atrial dilation: Fetal presentation

“…A histological section demonstrated primarily layers of collagen and smooth muscle cells with interspersed islands of atrial myocytes. 5 It is important to distinguish this anomaly from other cause of right atrial dilation especially tricuspid valve dysplasia and Ebstein anomaly. Most patients are asymptomatic with some presenting with atrial arrhythmias or thrombus formation.…”

“…Most patients are asymptomatic with some presenting with atrial arrhythmias or thrombus formation. 5 It is important to distinguish this anomaly from other cause of right atrial dilation especially tricuspid valve dysplasia and Ebstein anomaly. Surgical resection, anticoagulation, catheter-based ablation, and watchful waiting…”