Introduction
A single ventricle (SV) heart defect is a rare complex congenital cardiac malformation, accounting for approximately 1%-2% of congenital heart diseases.1SV is more commonly referred to as two-sided atrioventricular valves or a common atrioventricular valve opening in one ventricle. Patients with SV have only one functional ventricular chamber, and blood from the body and pulmonary circulation is mixed in the heart chamber, often causing overload in the single functional ventricular chamber and leading to heart failure in the early stages.2Surgical intervention is the mainstay treatment for SV patients, although patients who do not receivesurgical intervention may also survive. For example, it was reported that among unoperated patients with single-ventricular hearts, the first-year survival rate was 10 percent to 30 percent, with a median survival of 14 years.3 In this study, we report four adult patients who had SV since birth without surgical intervention and survived to adulthood. All the case information and the images (Figures 1-4) in this review have been approved by the ethics committee of our hospital.We also conducted a Medline search and reviewed similar cases published in recent years. In addition, we summarized the influence of treatment methods on the survival rate of SV patients in recent years.