Right ventricular (RV) hypoplasia with isolated myocardial disease and complete absence of RV trabeculae is a rare congenital heart disease, the current treatment of which is ineffective. Here, a rare case is presented of a middle-aged female patient with RV hypoplasia complicated by tricuspid regurgitation, right atrial thrombus, and atrial fibrillation. The patient was treated with a one-and-a-half ventricular repair, and showed significant improvements in cardiac function and physical activity tolerance. The study results suggest that this surgical approach can significantly improve the prognosis of an adult patient with isolated RV hypoplasia.