BACKGROUND: Congenital right ventricular aneurysm (CVA) and diverticulum (CVD) are rare heart diseases that can be diagnosed prenatally. Data on the natural progression of ventricular aneurysms or diverticula identified during fetal life remains scarce, with insights primarily derived from a limited number of case reports and case series. This case report aims to highlight the diagnosis, management, and outcomes of a rare right ventricular free wall aneurysm progressing to hypoplastic right heart syndrome (HRHS), utilizing advanced fetal imaging and prenatal therapy. These findings provide valuable perspective on the underlying cause, diagnostic approaches, and treatment strategy for rare cardiac anomaly. CASE DESCRIPTION: The aneurysm of the right ventricular free wall was diagnosed 13 weeks of gestation during prenatal ultrasound of the fetus in the first trimester. At the time of diagnosis, severe tricuspid valve stenosis with severe tricuspid regurgitation, critical pulmonary stenosis, pericardial effusion, ascites, and secondary flow reversal in the ductus venosus was found. Genetic testing using microarray-based comparative genomic hybridization (aCGH) on amniotic fluid samples showed no genomic imbalance. Digoxin treatment was initiated at 13 weeks of gestation, starting with a loading dose of 1,200 micrograms, followed by a maintenance dose of 375 micrograms daily, to address signs of fetal heart failure. The CONCLUSIONS: CVAs are rare but significant anomalies with potential for severe hemodynamic consequences. Multidisciplinary approaches integrating advanced imaging techniques, prenatal counseling, and tailored postnatal management are essential for optimizing outcomes.