3 | DISCUSSION
Compared with left atrial appendage aneurysm, RAAA is a rare cardiac anomaly that was first reported in 2001 which thought to be caused by dysplasia of the muscular wall of the right atrium (RA) and right atrial appendage.7,8 Most of these aneurysms affect adults in their third decade of life but they can also occur in children and neonates and can also be detected prenatally.2,3
The diagnosis can be confirmed by imaging modalities, especially initial echocardiography and chest X-ray.9 Both TTE and TEE are very effective in diagnosis and distinguish of the aneurysm, such as pericardial cysts, Ebstein’s anomaly, cortriatriatum and thrombosis.10Agitated saline study with echocardiography can be performed to confirm the diagnosis and to distinguish from pericardial effusion or cysts, demonstrating opacification of the RAAA and RV.2 TEE plays an important role in further preoperative evaluation and planning surgical procedures during resection of RAAA. In this case, before the aneurysm resection TEE presented the giant RAAA, PFO and RV compression. During the surgery, surgeons concerned the resection of the aneurysm might change the entire anatomical structure, leading to tricuspid valve dysfunction. Additionally TEE played a key role in confirming valve competency during the surgery. In this case, the postoperative TEE confirmed that the tricuspid valve still functioned normally without regurgitation or insufficiency. Therefore, the patient was not indicated to tricuspid valvuloplasty. Taken together, TEE is very helpful for surgeons to formulate detailed surgical plan and evaluate the effect of surgical correction during cardiac surgery. Finally, TTE is useful for long-term follow-up on this case since there is no report regarding postoperative recurrence or death after RAAA resection.
Although RAAA is a very rare anomaly in pediatric patients, prenatal diagnosis via fetal echocardiography is possible. Clinical experience of treatment for RAAA is limited and the natural history and optimal management strategy are still unclear. Therefore, the therapeutic strategies of RAAA remain controversial and aneurysm resection and anticoagulation therapy are not recommended in all cases.3 Surgical resection is preferred for patients with symptoms or progressive enlargement in preventing thromboembolisms and lowering the risk of atrial arrhythmia and heart failure, which are the most common complications of these aneurysms.2,3Oral anticoagulants is recommended to reduce the risk of thromboembolic events in patients with contraindications to surgery.4
In conclusion, echocardiography plays an important role in the diagnosis and surgical resection of RAAA as well as postoperative evaluation of surgical effect. Treatment should be modified according to the age, presentation, imaging findings and the follow-up results.