Transcatheter dual-device closure for symptomatic iatrogenic atrial septal defect following bioprosthetic mitral valve replacement: a case report

Iatrogenic atrial septal defect (iASD) is a relatively common complication after cardiac surgical or catheter-based procedures involving transseptal access. While most defects close spontaneously, a subset may persist and become hemodynamically significant, leading to clinical deterioration and necessitating intervention. We report a case of a large, persistent iASD that led to progressive right-sided heart failure following bioprosthetic mitral valve replacement combined with tricuspid annuloplasty. A 69-year-old male underwent bioprosthetic mitral valve replacement and tricuspid annuloplasty. Postoperatively, the patient developed a large, persistent iASD, which contributed to severe right-sided heart failure. The patient also had end-stage liver disease, portal hypertension, and severe coagulopathy, which made reoperation extremely high-risk. After heart team evaluation, a transcatheter closure approach was chosen. Initially, a 24-mm occluder was deployed, but significant residual shunting remained. A planned two-device strategy was then performed, resulting in complete closure of the defect. Post-procedure imaging confirmed the absence of residual shunt, and tricuspid regurgitation significantly improved. The patient's symptoms improved to New York Heart Association NYHA I-II, and at six-month follow-up, the device remained stable, and cardiac function had recovered. This case illustrates that in patients with large, complex, or poorly rimmed iASDs, particularly those who are not suitable candidates for reoperation, the dual-device strategy represents a safe and effective percutaneous alternative.