Giant right atrial cystic hamartoma: a case report and literature review

Abstract

An 11-year-old boy presenting with palpitation and chest distress was found to have gross cardiomegaly on chest radiography. Subsequent echocardiography revealed an intramural giant cystic mass in the right atrium. An operative measure was planned to prevent acute cardiac tamponade and right coronary artery obstruction. The patient successfully underwent open cystectomy to remove the mass, which was located on the front wall of the right atrium and extended to the atrioventricular appendage. Histopathological examination confirmed a cystic hamartoma. To the best of our knowledge, this is the first reported case of a giant cystic hamartoma located on the right atrium.

Trial registration number: 704640.

Figure 1

(A) Transthoracic echocardiography displayed a right atrium mass of approximately 9 cm and caused compression of the whole regions of the right atrium and deviation of the cardiac structures to the left. RA, right atrium; RV, right ventricle. (B) Contrast-enhanced CT scan showing a large cystic structure in the right atrium.

Figure 2

Appearance of the right atrial wall after partial cystotomy.

Figure 3

Microscopic features of hamartomas in surgical tissue. (A–C) Myocyte disorganisation and focal pericellular interstitial haemorrhage, oedema and fibrosis, myocyte hypertrophy, interstitial fibrosis, thickened intramural coronary arteries and dilated venule were present, chronic inflammatory cell dispersed infiltration (H&E stain: A and B ×100; C ×200). (D) Abundant fibrous connective tissue and malformed blood vessels (CD₃₄ positive) (D ×100 SP).