Technical Standards | Fuwai Hospital's Liu Yuhao Team Achieves Interventional Closure of Giant 35mm PDA via 3D Printing Technology

Clinical Challenge The patient, a 36-year-old female, presented with an extremely rare giant Patent Ductus Arteriosus (PDA). Pre-operative imaging confirmed a defect diameter of 35mm. Current medical literature cites 28mm as the previous global maximum for successful interventional PDA closure. The anatomical scale of this case rendered all standard PDA-specific occluders (which typically top out at 24mm) obsolete, compounded by severe pulmonary hypertension and symptoms of heart failure.

Decision Logic The Structural Heart Disease team at Fuwai Hospital (led by Dr. Liu Yuhao, Dr. Zhao Yipin, Dr. Chen Chong, Dr. Wang Xiaohu, and Dr. Chen Tongfeng) executed a highly customized interventional strategy:

1. High-Fidelity Model Validation: 3D printing was employed to create a 1:1 physical model based on CT data. Extracorporeal simulations evaluated the relationship between the occluder and surrounding structures (aortic arch and pulmonary branches), confirming the feasibility of "cross-category device utilization."
2. Device Modification: A 36mm ASD occluder was selected as the framework. To address the risk of hemolysis posed by the ASD device's structure under high-velocity PDA shunting, the team manually reinforced the central waist layers to enhance structural integrity and sealing efficacy.
3. Delivery Innovation: As the modified device exceeded the capacity of standard PDA sheaths, the team innovatively utilized a specialized large-diameter long sheath to ensure compatible and precise deployment.

Patient Benefit Led by Dr. Liu Yuhao, the expert team achieved perfect apposition of the modified device. Post-operative color Doppler confirmed the complete elimination of the shunt and a significant reduction in pulmonary artery pressure. This case not only resets the maximum diameter threshold for PDA intervention but also serves as a "Fuwai Benchmark" for minimally invasive treatment of complex congenital heart defects.