ELS usually occurs between left lower lobe and diaphragm [
2]. It mostly manifests in infancy stage and approximately 60% of ELS is associated with other congenital abnormalities, such as foregut malformations and cardiac anomalies [
3]. In our case, the patient is a young adult woman with a mass located in superior anterior mediastinum, which is particularly unusual in gender, onset age and pathogenic site. Moreover, she also has concurrent CAP and ASD. Only three cases about ELS accompanied by CAP have been reported up to now [
4‐
6]. Our case is the first to report ELS, CAP and ASD at the same time. The association between pathogenesis of ELS, CAP and ASD has not been clarified yet.Clinical manifestation of ELS include non-specific symptoms due to secondary pulmonary infection, mass effect and congenital anomalies-related symptoms. There are also a few asymptomatic patients having been diagnosed incidentally [
2]. Our patient had no signs of infection and her symptoms were most probably attributable to mass effect. According to the rarity of ELS, higher prevalence of cystic teratoma in young women, and nonspecific results of her enhanced CT, we regarded cystic teratoma as the first preoperative diagnosis. CAP can be ignored preoperatively even if we have done enhanced CT. The thin fat layer in that position makes it difficult to discover CAP from enhanced CT. But enhanced CT can actually offer some significant evidence, such as levorotation of heart and interposition of lung tissue in regions of absent pericardium, including anterior space between aorta and pulmonary artery. With those signs, cardiac magnetic resonance imaging is a recommended choice, regarded as gold standard [
7]. Regretfully, there is not any significant signs either in this patient.
Surgical resection remains the standard treatment for ELS. To symptomatic patients, such as infection or hemoptysis, confine operation is recommended. To asymptomatic patients, selective surgery can be performed under regularly monitoring. Of uncertain cases, surgery is also a proper way to identify uncertain cases [
1,
2,
8]. Video-assisted thoracoscopic surgery is as effective and safe as thoracotomy for ELS [
1,
8]. For our patient, we only performed a video-assisted thoracoscopic surgery mediastinal cystectomy and did not interfere with CAP and ASD.In conclusion, ELS may be combined with CAP and ASD at the same time. Its preoperative diagnostic rate remains quite low due to nonspecific imaging manifestations. Asymptomatic CAP is also difficult to be discovered. A cardiac magnetic resonance imaging is highly recommended if there are indirect signs. An operation should be performed when diagnose is certain. The most common treatment is regular observation to asymptomatic CAP and ASD. For patients with the complete bilateral or complete left-sided absence of the pericardium, no treatment is indicated [
9]. According to the guideline of European Society of Cardiology, We suggested the Interventional therapy for the patient after operation. But the patient refused for her own consideration, we will continue to track the patient’s condition in our clinic.